From 0338a3497961eaaa7bc01b74c611208429385ea9 Mon Sep 17 00:00:00 2001 From: Christian Hoff Date: Sun, 26 Sep 2021 18:54:51 +0200 Subject: [PATCH] Update binder to the latest version Over the last years, many fixes and changes have been applied to Binder in the Linux kernel, but these fixes were never backported to anbox-modules. The meant that the version of Binder in anbox-modules was very outdated. With this commit, Binder has been update to the latest state from the Linux kernel. This should also fix the compile on kernel 5.12 and later. --- .gitignore | 9 + binder/Makefile | 6 +- binder/binder.c | 5433 +++++++++++++++++++++++++------------- binder/binder.h | 51 +- binder/binder_alloc.c | 1295 +++++++++ binder/binder_alloc.h | 181 ++ binder/binder_internal.h | 150 ++ binder/binder_trace.h | 152 +- binder/binderfs.c | 812 ++++++ binder/deps.c | 163 +- binder/deps.h | 5 + 11 files changed, 6276 insertions(+), 1981 deletions(-) create mode 100644 .gitignore create mode 100644 binder/binder_alloc.c create mode 100644 binder/binder_alloc.h create mode 100644 binder/binder_internal.h create mode 100644 binder/binderfs.c create mode 100644 binder/deps.h diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..f027588 --- /dev/null +++ b/.gitignore @@ -0,0 +1,9 @@ +*.ko +*.mod +*.mod.c +*.o +*.order +*.symvers +*.swp +.*.cmd +.tmp_versions diff --git a/binder/Makefile b/binder/Makefile index 96de63a..ee0d72b 100644 --- a/binder/Makefile +++ b/binder/Makefile @@ -1,6 +1,6 @@ -ccflags-y += -I$(src) -Wno-int-conversion -DCONFIG_ANDROID_BINDER_DEVICES="\"binder\"" +ccflags-y += -I$(src) -Wno-int-conversion -DCONFIG_ANDROID_BINDER_DEVICES="\"binder\"" -DCONFIG_ANDROID_BINDERFS="y" obj-m := binder_linux.o -binder_linux-y := deps.o binder.o +binder_linux-y := deps.o binder.o binder_alloc.o binderfs.o KERNEL_SRC ?= /lib/modules/$(shell uname -r)/build @@ -11,4 +11,4 @@ install: cp binder_linux.ko $(DESTDIR)/ clean: - rm -rf deps.h *.o *.ko *.mod.c *.symvers *.order .*.cmd .tmp_versions + rm -rf *.o *.ko *.mod.c *.symvers *.order .*.cmd .tmp_versions diff --git a/binder/binder.c b/binder/binder.c index aaac689..d098993 100644 --- a/binder/binder.c +++ b/binder/binder.c @@ -1,117 +1,100 @@ +// SPDX-License-Identifier: GPL-2.0-only /* binder.c * * Android IPC Subsystem * * Copyright (C) 2007-2008 Google, Inc. + */ + +/* + * Locking overview * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. + * There are 3 main spinlocks which must be acquired in the + * order shown: * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. + * 1) proc->outer_lock : protects binder_ref + * binder_proc_lock() and binder_proc_unlock() are + * used to acq/rel. + * 2) node->lock : protects most fields of binder_node. + * binder_node_lock() and binder_node_unlock() are + * used to acq/rel + * 3) proc->inner_lock : protects the thread and node lists + * (proc->threads, proc->waiting_threads, proc->nodes) + * and all todo lists associated with the binder_proc + * (proc->todo, thread->todo, proc->delivered_death and + * node->async_todo), as well as thread->transaction_stack + * binder_inner_proc_lock() and binder_inner_proc_unlock() + * are used to acq/rel * + * Any lock under procA must never be nested under any lock at the same + * level or below on procB. + * + * Functions that require a lock held on entry indicate which lock + * in the suffix of the function name: + * + * foo_olocked() : requires node->outer_lock + * foo_nlocked() : requires node->lock + * foo_ilocked() : requires proc->inner_lock + * foo_oilocked(): requires proc->outer_lock and proc->inner_lock + * foo_nilocked(): requires node->lock and proc->inner_lock + * ... */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt -#include -#include -#include #include #include #include #include #include -#include +#include #include #include #include #include #include #include -#include -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) #include #include -#else -#include -#include -#endif #include +#include #include -#include -#include #include #include -#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) -#include -#endif +#include +#include +#include +#include +#include -#ifdef CONFIG_ANDROID_BINDER_IPC_32BIT -#define BINDER_IPC_32BIT 1 -#endif +#include +#include -/* Until I upstream a better version of this patch choose an arbitrary major - * number in the high end spectrum that has not yet been given away and is - * unlikely to be given away in the near future. - */ -#define BINDER_DKMS_MAJOR 511 -#define BINDER_DKMS_MAX_MINOR 1024 +#include -#include "binder.h" +#include "binder_alloc.h" +#include "binder_internal.h" #include "binder_trace.h" -#ifndef MAX_NICE -#define MAX_NICE 19 -#endif - -static DEFINE_MUTEX(binder_main_lock); +static HLIST_HEAD(binder_deferred_list); static DEFINE_MUTEX(binder_deferred_lock); -static DEFINE_MUTEX(binder_mmap_lock); -static DEFINE_MUTEX(binder_devices_mtx); static HLIST_HEAD(binder_devices); static HLIST_HEAD(binder_procs); -static HLIST_HEAD(binder_deferred_list); +static DEFINE_MUTEX(binder_procs_lock); + static HLIST_HEAD(binder_dead_nodes); +static DEFINE_SPINLOCK(binder_dead_nodes_lock); static struct dentry *binder_debugfs_dir_entry_root; static struct dentry *binder_debugfs_dir_entry_proc; -static int binder_last_id; +static atomic_t binder_last_id; -#define BINDER_DEBUG_ENTRY(name) \ -static int binder_##name##_open(struct inode *inode, struct file *file) \ -{ \ - return single_open(file, binder_##name##_show, inode->i_private); \ -} \ -\ -static const struct file_operations binder_##name##_fops = { \ - .owner = THIS_MODULE, \ - .open = binder_##name##_open, \ - .read = seq_read, \ - .llseek = seq_lseek, \ - .release = single_release, \ -} - -static int binder_proc_show(struct seq_file *m, void *unused); -BINDER_DEBUG_ENTRY(proc); - -/* This is only defined in include/asm-arm/sizes.h */ -#ifndef SZ_1K -#define SZ_1K 0x400 -#endif - -#ifndef SZ_4M -#define SZ_4M 0x400000 -#endif +static int proc_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(proc); #define FORBIDDEN_MMAP_FLAGS (VM_WRITE) -#define BINDER_SMALL_BUF_SIZE (PAGE_SIZE * 64) - enum { BINDER_DEBUG_USER_ERROR = 1U << 0, BINDER_DEBUG_FAILED_TRANSACTION = 1U << 1, @@ -126,29 +109,20 @@ enum { BINDER_DEBUG_TRANSACTION_COMPLETE = 1U << 10, BINDER_DEBUG_FREE_BUFFER = 1U << 11, BINDER_DEBUG_INTERNAL_REFS = 1U << 12, - BINDER_DEBUG_BUFFER_ALLOC = 1U << 13, - BINDER_DEBUG_PRIORITY_CAP = 1U << 14, - BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 15, + BINDER_DEBUG_PRIORITY_CAP = 1U << 13, + BINDER_DEBUG_SPINLOCKS = 1U << 14, }; static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR | BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION; -module_param_named(debug_mask, binder_debug_mask, uint, S_IWUSR | S_IRUGO); -static bool binder_debug_no_lock; -module_param_named(proc_no_lock, binder_debug_no_lock, bool, S_IWUSR | S_IRUGO); - -static int binder_devices_param = 1; -module_param_named(num_devices, binder_devices_param, int, 0444); +char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; +module_param_named(devices, binder_devices_param, charp, 0444); static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait); static int binder_stop_on_user_error; static int binder_set_stop_on_user_error(const char *val, -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 15, 0) const struct kernel_param *kp) -#else - struct kernel_param *kp) -#endif { int ret; @@ -158,18 +132,18 @@ static int binder_set_stop_on_user_error(const char *val, return ret; } module_param_call(stop_on_user_error, binder_set_stop_on_user_error, - param_get_int, &binder_stop_on_user_error, S_IWUSR | S_IRUGO); + param_get_int, &binder_stop_on_user_error, 0644); #define binder_debug(mask, x...) \ do { \ if (binder_debug_mask & mask) \ - pr_info(x); \ + pr_info_ratelimited(x); \ } while (0) #define binder_user_error(x...) \ do { \ if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) \ - pr_info(x); \ + pr_info_ratelimited(x); \ if (binder_stop_on_user_error) \ binder_stop_on_user_error = 2; \ } while (0) @@ -197,78 +171,61 @@ enum binder_stat_types { }; struct binder_stats { - int br[_IOC_NR(BR_FAILED_REPLY) + 1]; - int bc[_IOC_NR(BC_REPLY_SG) + 1]; - int obj_created[BINDER_STAT_COUNT]; - int obj_deleted[BINDER_STAT_COUNT]; + atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1]; + atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1]; + atomic_t obj_created[BINDER_STAT_COUNT]; + atomic_t obj_deleted[BINDER_STAT_COUNT]; }; static struct binder_stats binder_stats; static inline void binder_stats_deleted(enum binder_stat_types type) { - binder_stats.obj_deleted[type]++; + atomic_inc(&binder_stats.obj_deleted[type]); } static inline void binder_stats_created(enum binder_stat_types type) { - binder_stats.obj_created[type]++; + atomic_inc(&binder_stats.obj_created[type]); } -struct binder_transaction_log_entry { - int debug_id; - int call_type; - int from_proc; - int from_thread; - int target_handle; - int to_proc; - int to_thread; - int to_node; - int data_size; - int offsets_size; - const char *context_name; -}; -struct binder_transaction_log { - int next; - int full; - struct binder_transaction_log_entry entry[32]; -}; -static struct binder_transaction_log binder_transaction_log; -static struct binder_transaction_log binder_transaction_log_failed; +struct binder_transaction_log binder_transaction_log; +struct binder_transaction_log binder_transaction_log_failed; static struct binder_transaction_log_entry *binder_transaction_log_add( struct binder_transaction_log *log) { struct binder_transaction_log_entry *e; + unsigned int cur = atomic_inc_return(&log->cur); - e = &log->entry[log->next]; + if (cur >= ARRAY_SIZE(log->entry)) + log->full = true; + e = &log->entry[cur % ARRAY_SIZE(log->entry)]; + WRITE_ONCE(e->debug_id_done, 0); + /* + * write-barrier to synchronize access to e->debug_id_done. + * We make sure the initialized 0 value is seen before + * memset() other fields are zeroed by memset. + */ + smp_wmb(); memset(e, 0, sizeof(*e)); - log->next++; - if (log->next == ARRAY_SIZE(log->entry)) { - log->next = 0; - log->full = 1; - } return e; } -struct binder_context { - struct binder_node *binder_context_mgr_node; - kuid_t binder_context_mgr_uid; - const char *name; -}; - -struct binder_device { - struct hlist_node hlist; - struct cdev cdev; - struct device class_dev; - struct binder_context context; -}; - +/** + * struct binder_work - work enqueued on a worklist + * @entry: node enqueued on list + * @type: type of work to be performed + * + * There are separate work lists for proc, thread, and node (async). + */ struct binder_work { struct list_head entry; - enum { + + enum binder_work_type { BINDER_WORK_TRANSACTION = 1, BINDER_WORK_TRANSACTION_COMPLETE, + BINDER_WORK_RETURN_ERROR, BINDER_WORK_NODE, BINDER_WORK_DEAD_BINDER, BINDER_WORK_DEAD_BINDER_AND_CLEAR, @@ -276,8 +233,74 @@ struct binder_work { } type; }; +struct binder_error { + struct binder_work work; + uint32_t cmd; +}; + +/** + * struct binder_node - binder node bookkeeping + * @debug_id: unique ID for debugging + * (invariant after initialized) + * @lock: lock for node fields + * @work: worklist element for node work + * (protected by @proc->inner_lock) + * @rb_node: element for proc->nodes tree + * (protected by @proc->inner_lock) + * @dead_node: element for binder_dead_nodes list + * (protected by binder_dead_nodes_lock) + * @proc: binder_proc that owns this node + * (invariant after initialized) + * @refs: list of references on this node + * (protected by @lock) + * @internal_strong_refs: used to take strong references when + * initiating a transaction + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_weak_refs: weak user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @local_strong_refs: strong user refs from local process + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @tmp_refs: temporary kernel refs + * (protected by @proc->inner_lock while @proc + * is valid, and by binder_dead_nodes_lock + * if @proc is NULL. During inc/dec and node release + * it is also protected by @lock to provide safety + * as the node dies and @proc becomes NULL) + * @ptr: userspace pointer for node + * (invariant, no lock needed) + * @cookie: userspace cookie for node + * (invariant, no lock needed) + * @has_strong_ref: userspace notified of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_strong_ref: userspace has acked notification of strong ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_weak_ref: userspace notified of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @pending_weak_ref: userspace has acked notification of weak ref + * (protected by @proc->inner_lock if @proc + * and by @lock) + * @has_async_transaction: async transaction to node in progress + * (protected by @lock) + * @accept_fds: file descriptor operations supported for node + * (invariant after initialized) + * @min_priority: minimum scheduling priority + * (invariant after initialized) + * @txn_security_ctx: require sender's security context + * (invariant after initialized) + * @async_todo: list of async work items + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder nodes. + */ struct binder_node { int debug_id; + spinlock_t lock; struct binder_work work; union { struct rb_node rb_node; @@ -288,99 +311,177 @@ struct binder_node { int internal_strong_refs; int local_weak_refs; int local_strong_refs; + int tmp_refs; binder_uintptr_t ptr; binder_uintptr_t cookie; - unsigned has_strong_ref:1; - unsigned pending_strong_ref:1; - unsigned has_weak_ref:1; - unsigned pending_weak_ref:1; - unsigned has_async_transaction:1; - unsigned accept_fds:1; - unsigned min_priority:8; + struct { + /* + * bitfield elements protected by + * proc inner_lock + */ + u8 has_strong_ref:1; + u8 pending_strong_ref:1; + u8 has_weak_ref:1; + u8 pending_weak_ref:1; + }; + struct { + /* + * invariant after initialization + */ + u8 accept_fds:1; + u8 txn_security_ctx:1; + u8 min_priority; + }; + bool has_async_transaction; struct list_head async_todo; }; struct binder_ref_death { + /** + * @work: worklist element for death notifications + * (protected by inner_lock of the proc that + * this ref belongs to) + */ struct binder_work work; binder_uintptr_t cookie; }; +/** + * struct binder_ref_data - binder_ref counts and id + * @debug_id: unique ID for the ref + * @desc: unique userspace handle for ref + * @strong: strong ref count (debugging only if not locked) + * @weak: weak ref count (debugging only if not locked) + * + * Structure to hold ref count and ref id information. Since + * the actual ref can only be accessed with a lock, this structure + * is used to return information about the ref to callers of + * ref inc/dec functions. + */ +struct binder_ref_data { + int debug_id; + uint32_t desc; + int strong; + int weak; +}; + +/** + * struct binder_ref - struct to track references on nodes + * @data: binder_ref_data containing id, handle, and current refcounts + * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree + * @rb_node_node: node for lookup by @node in proc's rb_tree + * @node_entry: list entry for node->refs list in target node + * (protected by @node->lock) + * @proc: binder_proc containing ref + * @node: binder_node of target node. When cleaning up a + * ref for deletion in binder_cleanup_ref, a non-NULL + * @node indicates the node must be freed + * @death: pointer to death notification (ref_death) if requested + * (protected by @node->lock) + * + * Structure to track references from procA to target node (on procB). This + * structure is unsafe to access without holding @proc->outer_lock. + */ struct binder_ref { /* Lookups needed: */ /* node + proc => ref (transaction) */ /* desc + proc => ref (transaction, inc/dec ref) */ /* node => refs + procs (proc exit) */ - int debug_id; + struct binder_ref_data data; struct rb_node rb_node_desc; struct rb_node rb_node_node; struct hlist_node node_entry; struct binder_proc *proc; struct binder_node *node; - uint32_t desc; - int strong; - int weak; struct binder_ref_death *death; }; -struct binder_buffer { - struct list_head entry; /* free and allocated entries by address */ - struct rb_node rb_node; /* free entry by size or allocated entry */ - /* by address */ - unsigned free:1; - unsigned allow_user_free:1; - unsigned async_transaction:1; - unsigned debug_id:29; - - struct binder_transaction *transaction; - - struct binder_node *target_node; - size_t data_size; - size_t offsets_size; - size_t extra_buffers_size; - uint8_t data[0]; -}; - enum binder_deferred_state { - BINDER_DEFERRED_PUT_FILES = 0x01, - BINDER_DEFERRED_FLUSH = 0x02, - BINDER_DEFERRED_RELEASE = 0x04, + BINDER_DEFERRED_FLUSH = 0x01, + BINDER_DEFERRED_RELEASE = 0x02, }; +/** + * struct binder_proc - binder process bookkeeping + * @proc_node: element for binder_procs list + * @threads: rbtree of binder_threads in this proc + * (protected by @inner_lock) + * @nodes: rbtree of binder nodes associated with + * this proc ordered by node->ptr + * (protected by @inner_lock) + * @refs_by_desc: rbtree of refs ordered by ref->desc + * (protected by @outer_lock) + * @refs_by_node: rbtree of refs ordered by ref->node + * (protected by @outer_lock) + * @waiting_threads: threads currently waiting for proc work + * (protected by @inner_lock) + * @pid PID of group_leader of process + * (invariant after initialized) + * @tsk task_struct for group_leader of process + * (invariant after initialized) + * @deferred_work_node: element for binder_deferred_list + * (protected by binder_deferred_lock) + * @deferred_work: bitmap of deferred work to perform + * (protected by binder_deferred_lock) + * @is_dead: process is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @inner_lock) + * @todo: list of work for this process + * (protected by @inner_lock) + * @stats: per-process binder statistics + * (atomics, no lock needed) + * @delivered_death: list of delivered death notification + * (protected by @inner_lock) + * @max_threads: cap on number of binder threads + * (protected by @inner_lock) + * @requested_threads: number of binder threads requested but not + * yet started. In current implementation, can + * only be 0 or 1. + * (protected by @inner_lock) + * @requested_threads_started: number binder threads started + * (protected by @inner_lock) + * @tmp_ref: temporary reference to indicate proc is in use + * (protected by @inner_lock) + * @default_priority: default scheduler priority + * (invariant after initialized) + * @debugfs_entry: debugfs node + * @alloc: binder allocator bookkeeping + * @context: binder_context for this proc + * (invariant after initialized) + * @inner_lock: can nest under outer_lock and/or node lock + * @outer_lock: no nesting under innor or node lock + * Lock order: 1) outer, 2) node, 3) inner + * @binderfs_entry: process-specific binderfs log file + * + * Bookkeeping structure for binder processes + */ struct binder_proc { struct hlist_node proc_node; struct rb_root threads; struct rb_root nodes; struct rb_root refs_by_desc; struct rb_root refs_by_node; + struct list_head waiting_threads; int pid; - struct vm_area_struct *vma; - struct mm_struct *vma_vm_mm; struct task_struct *tsk; - struct files_struct *files; struct hlist_node deferred_work_node; int deferred_work; - void *buffer; - ptrdiff_t user_buffer_offset; + bool is_dead; - struct list_head buffers; - struct rb_root free_buffers; - struct rb_root allocated_buffers; - size_t free_async_space; - - struct page **pages; - size_t buffer_size; - uint32_t buffer_free; struct list_head todo; - wait_queue_head_t wait; struct binder_stats stats; struct list_head delivered_death; int max_threads; int requested_threads; int requested_threads_started; - int ready_threads; + int tmp_ref; long default_priority; struct dentry *debugfs_entry; + struct binder_alloc alloc; struct binder_context *context; + spinlock_t inner_lock; + spinlock_t outer_lock; + struct dentry *binderfs_entry; }; enum { @@ -389,22 +490,78 @@ enum { BINDER_LOOPER_STATE_EXITED = 0x04, BINDER_LOOPER_STATE_INVALID = 0x08, BINDER_LOOPER_STATE_WAITING = 0x10, - BINDER_LOOPER_STATE_NEED_RETURN = 0x20 + BINDER_LOOPER_STATE_POLL = 0x20, }; +/** + * struct binder_thread - binder thread bookkeeping + * @proc: binder process for this thread + * (invariant after initialization) + * @rb_node: element for proc->threads rbtree + * (protected by @proc->inner_lock) + * @waiting_thread_node: element for @proc->waiting_threads list + * (protected by @proc->inner_lock) + * @pid: PID for this thread + * (invariant after initialization) + * @looper: bitmap of looping state + * (only accessed by this thread) + * @looper_needs_return: looping thread needs to exit driver + * (no lock needed) + * @transaction_stack: stack of in-progress transactions for this thread + * (protected by @proc->inner_lock) + * @todo: list of work to do for this thread + * (protected by @proc->inner_lock) + * @process_todo: whether work in @todo should be processed + * (protected by @proc->inner_lock) + * @return_error: transaction errors reported by this thread + * (only accessed by this thread) + * @reply_error: transaction errors reported by target thread + * (protected by @proc->inner_lock) + * @wait: wait queue for thread work + * @stats: per-thread statistics + * (atomics, no lock needed) + * @tmp_ref: temporary reference to indicate thread is in use + * (atomic since @proc->inner_lock cannot + * always be acquired) + * @is_dead: thread is dead and awaiting free + * when outstanding transactions are cleaned up + * (protected by @proc->inner_lock) + * + * Bookkeeping structure for binder threads. + */ struct binder_thread { struct binder_proc *proc; struct rb_node rb_node; + struct list_head waiting_thread_node; int pid; - int looper; + int looper; /* only modified by this thread */ + bool looper_need_return; /* can be written by other thread */ struct binder_transaction *transaction_stack; struct list_head todo; - uint32_t return_error; /* Write failed, return error code in read buf */ - uint32_t return_error2; /* Write failed, return error code in read */ - /* buffer. Used when sending a reply to a dead process that */ - /* we are also waiting on */ + bool process_todo; + struct binder_error return_error; + struct binder_error reply_error; wait_queue_head_t wait; struct binder_stats stats; + atomic_t tmp_ref; + bool is_dead; +}; + +/** + * struct binder_txn_fd_fixup - transaction fd fixup list element + * @fixup_entry: list entry + * @file: struct file to be associated with new fd + * @offset: offset in buffer data to this fixup + * + * List element for fd fixups in a transaction. Since file + * descriptors need to be allocated in the context of the + * target process, we pass each fd to be processed in this + * struct. + */ +struct binder_txn_fd_fixup { + struct list_head fixup_entry; + struct file *file; + size_t offset; }; struct binder_transaction { @@ -424,83 +581,442 @@ struct binder_transaction { long priority; long saved_priority; kuid_t sender_euid; + struct list_head fd_fixups; + binder_uintptr_t security_ctx; + /** + * @lock: protects @from, @to_proc, and @to_thread + * + * @from, @to_proc, and @to_thread can be set to NULL + * during thread teardown + */ + spinlock_t lock; }; +/** + * struct binder_object - union of flat binder object types + * @hdr: generic object header + * @fbo: binder object (nodes and refs) + * @fdo: file descriptor object + * @bbo: binder buffer pointer + * @fdao: file descriptor array + * + * Used for type-independent object copies + */ +struct binder_object { + union { + struct binder_object_header hdr; + struct flat_binder_object fbo; + struct binder_fd_object fdo; + struct binder_buffer_object bbo; + struct binder_fd_array_object fdao; + }; +}; + +/** + * binder_proc_lock() - Acquire outer lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->outer_lock. Used to protect binder_ref + * structures associated with the given proc. + */ +#define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__) +static void +_binder_proc_lock(struct binder_proc *proc, int line) + __acquires(&proc->outer_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->outer_lock); +} + +/** + * binder_proc_unlock() - Release spinlock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_proc_lock() + */ +#define binder_proc_unlock(_proc) _binder_proc_unlock(_proc, __LINE__) +static void +_binder_proc_unlock(struct binder_proc *proc, int line) + __releases(&proc->outer_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->outer_lock); +} + +/** + * binder_inner_proc_lock() - Acquire inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Acquires proc->inner_lock. Used to protect todo lists + */ +#define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__) +static void +_binder_inner_proc_lock(struct binder_proc *proc, int line) + __acquires(&proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&proc->inner_lock); +} + +/** + * binder_inner_proc_unlock() - Release inner lock for given binder_proc + * @proc: struct binder_proc to acquire + * + * Release lock acquired via binder_inner_proc_lock() + */ +#define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__) +static void +_binder_inner_proc_unlock(struct binder_proc *proc, int line) + __releases(&proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&proc->inner_lock); +} + +/** + * binder_node_lock() - Acquire spinlock for given binder_node + * @node: struct binder_node to acquire + * + * Acquires node->lock. Used to protect binder_node fields + */ +#define binder_node_lock(node) _binder_node_lock(node, __LINE__) +static void +_binder_node_lock(struct binder_node *node, int line) + __acquires(&node->lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); +} + +/** + * binder_node_unlock() - Release spinlock for given binder_proc + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_unlock(node) _binder_node_unlock(node, __LINE__) +static void +_binder_node_unlock(struct binder_node *node, int line) + __releases(&node->lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_unlock(&node->lock); +} + +/** + * binder_node_inner_lock() - Acquire node and inner locks + * @node: struct binder_node to acquire + * + * Acquires node->lock. If node->proc also acquires + * proc->inner_lock. Used to protect binder_node fields + */ +#define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__) +static void +_binder_node_inner_lock(struct binder_node *node, int line) + __acquires(&node->lock) __acquires(&node->proc->inner_lock) +{ + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + spin_lock(&node->lock); + if (node->proc) + binder_inner_proc_lock(node->proc); + else + /* annotation for sparse */ + __acquire(&node->proc->inner_lock); +} + +/** + * binder_node_unlock() - Release node and inner locks + * @node: struct binder_node to acquire + * + * Release lock acquired via binder_node_lock() + */ +#define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__) +static void +_binder_node_inner_unlock(struct binder_node *node, int line) + __releases(&node->lock) __releases(&node->proc->inner_lock) +{ + struct binder_proc *proc = node->proc; + + binder_debug(BINDER_DEBUG_SPINLOCKS, + "%s: line=%d\n", __func__, line); + if (proc) + binder_inner_proc_unlock(proc); + else + /* annotation for sparse */ + __release(&node->proc->inner_lock); + spin_unlock(&node->lock); +} + +static bool binder_worklist_empty_ilocked(struct list_head *list) +{ + return list_empty(list); +} + +/** + * binder_worklist_empty() - Check if no items on the work list + * @proc: binder_proc associated with list + * @list: list to check + * + * Return: true if there are no items on list, else false + */ +static bool binder_worklist_empty(struct binder_proc *proc, + struct list_head *list) +{ + bool ret; + + binder_inner_proc_lock(proc); + ret = binder_worklist_empty_ilocked(list); + binder_inner_proc_unlock(proc); + return ret; +} + +/** + * binder_enqueue_work_ilocked() - Add an item to the work list + * @work: struct binder_work to add to list + * @target_list: list to add work to + * + * Adds the work to the specified list. Asserts that work + * is not already on a list. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_work_ilocked(struct binder_work *work, + struct list_head *target_list) +{ + BUG_ON(target_list == NULL); + BUG_ON(work->entry.next && !list_empty(&work->entry)); + list_add_tail(&work->entry, target_list); +} + +/** + * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread. Doesn't set the process_todo + * flag, which means that (if it wasn't already set) the thread will go to + * sleep without handling this work when it calls read. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) +{ + WARN_ON(!list_empty(&thread->waiting_thread_node)); + binder_enqueue_work_ilocked(work, &thread->todo); +} + +/** + * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) +{ + WARN_ON(!list_empty(&thread->waiting_thread_node)); + binder_enqueue_work_ilocked(work, &thread->todo); + thread->process_todo = true; +} + +/** + * binder_enqueue_thread_work() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + */ +static void +binder_enqueue_thread_work(struct binder_thread *thread, + struct binder_work *work) +{ + binder_inner_proc_lock(thread->proc); + binder_enqueue_thread_work_ilocked(thread, work); + binder_inner_proc_unlock(thread->proc); +} + +static void +binder_dequeue_work_ilocked(struct binder_work *work) +{ + list_del_init(&work->entry); +} + +/** + * binder_dequeue_work() - Removes an item from the work list + * @proc: binder_proc associated with list + * @work: struct binder_work to remove from list + * + * Removes the specified work item from whatever list it is on. + * Can safely be called if work is not on any list. + */ +static void +binder_dequeue_work(struct binder_proc *proc, struct binder_work *work) +{ + binder_inner_proc_lock(proc); + binder_dequeue_work_ilocked(work); + binder_inner_proc_unlock(proc); +} + +static struct binder_work *binder_dequeue_work_head_ilocked( + struct list_head *list) +{ + struct binder_work *w; + + w = list_first_entry_or_null(list, struct binder_work, entry); + if (w) + list_del_init(&w->entry); + return w; +} + static void binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer); +static void binder_free_thread(struct binder_thread *thread); +static void binder_free_proc(struct binder_proc *proc); +static void binder_inc_node_tmpref_ilocked(struct binder_node *node); -static int task_get_unused_fd_flags(struct binder_proc *proc, int flags) +static bool binder_has_work_ilocked(struct binder_thread *thread, + bool do_proc_work) { - struct files_struct *files = proc->files; - unsigned long rlim_cur; - unsigned long irqs; - - if (files == NULL) - return -ESRCH; - - if (!lock_task_sighand(proc->tsk, &irqs)) - return -EMFILE; - - rlim_cur = task_rlimit(proc->tsk, RLIMIT_NOFILE); - unlock_task_sighand(proc->tsk, &irqs); - - return __alloc_fd(files, 0, rlim_cur, flags); + return thread->process_todo || + thread->looper_need_return || + (do_proc_work && + !binder_worklist_empty_ilocked(&thread->proc->todo)); } -/* - * copied from fd_install +static bool binder_has_work(struct binder_thread *thread, bool do_proc_work) +{ + bool has_work; + + binder_inner_proc_lock(thread->proc); + has_work = binder_has_work_ilocked(thread, do_proc_work); + binder_inner_proc_unlock(thread->proc); + + return has_work; +} + +static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread) +{ + return !thread->transaction_stack && + binder_worklist_empty_ilocked(&thread->todo) && + (thread->looper & (BINDER_LOOPER_STATE_ENTERED | + BINDER_LOOPER_STATE_REGISTERED)); +} + +static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc, + bool sync) +{ + struct rb_node *n; + struct binder_thread *thread; + + for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) { + thread = rb_entry(n, struct binder_thread, rb_node); + if (thread->looper & BINDER_LOOPER_STATE_POLL && + binder_available_for_proc_work_ilocked(thread)) { + if (sync) + wake_up_interruptible_sync(&thread->wait); + else + wake_up_interruptible(&thread->wait); + } + } +} + +/** + * binder_select_thread_ilocked() - selects a thread for doing proc work. + * @proc: process to select a thread from + * + * Note that calling this function moves the thread off the waiting_threads + * list, so it can only be woken up by the caller of this function, or a + * signal. Therefore, callers *should* always wake up the thread this function + * returns. + * + * Return: If there's a thread currently waiting for process work, + * returns that thread. Otherwise returns NULL. */ -static void task_fd_install( - struct binder_proc *proc, unsigned int fd, struct file *file) +static struct binder_thread * +binder_select_thread_ilocked(struct binder_proc *proc) { - if (proc->files) - __fd_install(proc->files, fd, file); + struct binder_thread *thread; + + assert_spin_locked(&proc->inner_lock); + thread = list_first_entry_or_null(&proc->waiting_threads, + struct binder_thread, + waiting_thread_node); + + if (thread) + list_del_init(&thread->waiting_thread_node); + + return thread; } -/* - * copied from sys_close +/** + * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work. + * @proc: process to wake up a thread in + * @thread: specific thread to wake-up (may be NULL) + * @sync: whether to do a synchronous wake-up + * + * This function wakes up a thread in the @proc process. + * The caller may provide a specific thread to wake-up in + * the @thread parameter. If @thread is NULL, this function + * will wake up threads that have called poll(). + * + * Note that for this function to work as expected, callers + * should first call binder_select_thread() to find a thread + * to handle the work (if they don't have a thread already), + * and pass the result into the @thread parameter. */ -static long task_close_fd(struct binder_proc *proc, unsigned int fd) +static void binder_wakeup_thread_ilocked(struct binder_proc *proc, + struct binder_thread *thread, + bool sync) { - int retval; + assert_spin_locked(&proc->inner_lock); - if (proc->files == NULL) - return -ESRCH; + if (thread) { + if (sync) + wake_up_interruptible_sync(&thread->wait); + else + wake_up_interruptible(&thread->wait); + return; + } - retval = __close_fd(proc->files, fd); - /* can't restart close syscall because file table entry was cleared */ - if (unlikely(retval == -ERESTARTSYS || - retval == -ERESTARTNOINTR || - retval == -ERESTARTNOHAND || - retval == -ERESTART_RESTARTBLOCK)) - retval = -EINTR; - - return retval; + /* Didn't find a thread waiting for proc work; this can happen + * in two scenarios: + * 1. All threads are busy handling transactions + * In that case, one of those threads should call back into + * the kernel driver soon and pick up this work. + * 2. Threads are using the (e)poll interface, in which case + * they may be blocked on the waitqueue without having been + * added to waiting_threads. For this case, we just iterate + * over all threads not handling transaction work, and + * wake them all up. We wake all because we don't know whether + * a thread that called into (e)poll is handling non-binder + * work currently. + */ + binder_wakeup_poll_threads_ilocked(proc, sync); } -static inline void binder_lock(const char *tag) +static void binder_wakeup_proc_ilocked(struct binder_proc *proc) { - trace_binder_lock(tag); - mutex_lock(&binder_main_lock); - trace_binder_locked(tag); -} + struct binder_thread *thread = binder_select_thread_ilocked(proc); -static inline void binder_unlock(const char *tag) -{ - trace_binder_unlock(tag); - mutex_unlock(&binder_main_lock); + binder_wakeup_thread_ilocked(proc, thread, /* sync = */false); } -#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 16, 0) -/* - * Convert rlimit style value [1,40] to nice value [-20, 19]. - */ -static inline long rlimit_to_nice(long prio) -{ - return (MAX_NICE - prio + 1); -} -#endif - static void binder_set_nice(long nice) { long min_nice; @@ -509,457 +1025,24 @@ static void binder_set_nice(long nice) set_user_nice(current, nice); return; } - min_nice = rlimit_to_nice(current->signal->rlim[RLIMIT_NICE].rlim_cur); + min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE)); binder_debug(BINDER_DEBUG_PRIORITY_CAP, "%d: nice value %ld not allowed use %ld instead\n", current->pid, nice, min_nice); set_user_nice(current, min_nice); if (min_nice <= MAX_NICE) return; + binder_user_error("%d RLIMIT_NICE not set\n", current->pid); } -static size_t binder_buffer_size(struct binder_proc *proc, - struct binder_buffer *buffer) -{ - if (list_is_last(&buffer->entry, &proc->buffers)) - return proc->buffer + proc->buffer_size - (void *)buffer->data; - return (size_t)list_entry(buffer->entry.next, - struct binder_buffer, entry) - (size_t)buffer->data; -} - -static void binder_insert_free_buffer(struct binder_proc *proc, - struct binder_buffer *new_buffer) -{ - struct rb_node **p = &proc->free_buffers.rb_node; - struct rb_node *parent = NULL; - struct binder_buffer *buffer; - size_t buffer_size; - size_t new_buffer_size; - - BUG_ON(!new_buffer->free); - - new_buffer_size = binder_buffer_size(proc, new_buffer); - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: add free buffer, size %zd, at %p\n", - proc->pid, new_buffer_size, new_buffer); - - while (*p) { - parent = *p; - buffer = rb_entry(parent, struct binder_buffer, rb_node); - BUG_ON(!buffer->free); - - buffer_size = binder_buffer_size(proc, buffer); - - if (new_buffer_size < buffer_size) - p = &parent->rb_left; - else - p = &parent->rb_right; - } - rb_link_node(&new_buffer->rb_node, parent, p); - rb_insert_color(&new_buffer->rb_node, &proc->free_buffers); -} - -static void binder_insert_allocated_buffer(struct binder_proc *proc, - struct binder_buffer *new_buffer) -{ - struct rb_node **p = &proc->allocated_buffers.rb_node; - struct rb_node *parent = NULL; - struct binder_buffer *buffer; - - BUG_ON(new_buffer->free); - - while (*p) { - parent = *p; - buffer = rb_entry(parent, struct binder_buffer, rb_node); - BUG_ON(buffer->free); - - if (new_buffer < buffer) - p = &parent->rb_left; - else if (new_buffer > buffer) - p = &parent->rb_right; - else - BUG(); - } - rb_link_node(&new_buffer->rb_node, parent, p); - rb_insert_color(&new_buffer->rb_node, &proc->allocated_buffers); -} - -static struct binder_buffer *binder_buffer_lookup(struct binder_proc *proc, - uintptr_t user_ptr) -{ - struct rb_node *n = proc->allocated_buffers.rb_node; - struct binder_buffer *buffer; - struct binder_buffer *kern_ptr; - - kern_ptr = (struct binder_buffer *)(user_ptr - proc->user_buffer_offset - - offsetof(struct binder_buffer, data)); - - while (n) { - buffer = rb_entry(n, struct binder_buffer, rb_node); - BUG_ON(buffer->free); - - if (kern_ptr < buffer) - n = n->rb_left; - else if (kern_ptr > buffer) - n = n->rb_right; - else - return buffer; - } - return NULL; -} - -static int binder_update_page_range(struct binder_proc *proc, int allocate, - void *start, void *end, - struct vm_area_struct *vma) -{ - void *page_addr; - unsigned long user_page_addr; - struct page **page; - struct mm_struct *mm; - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: %s pages %p-%p\n", proc->pid, - allocate ? "allocate" : "free", start, end); - - if (end <= start) - return 0; - - trace_binder_update_page_range(proc, allocate, start, end); - - if (vma) - mm = NULL; - else - mm = get_task_mm(proc->tsk); - - if (mm) { -#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) - mmap_write_lock(mm); -#else - down_write(&mm->mmap_sem); -#endif - vma = proc->vma; - if (vma && mm != proc->vma_vm_mm) { - pr_err("%d: vma mm and task mm mismatch\n", - proc->pid); - vma = NULL; - } - } - - if (allocate == 0) - goto free_range; - - if (vma == NULL) { - pr_err("%d: binder_alloc_buf failed to map pages in userspace, no vma\n", - proc->pid); - goto err_no_vma; - } - - for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { - int ret; - - page = &proc->pages[(page_addr - proc->buffer) / PAGE_SIZE]; - - BUG_ON(*page); - *page = alloc_page(GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO); - if (*page == NULL) { - pr_err("%d: binder_alloc_buf failed for page at %p\n", - proc->pid, page_addr); - goto err_alloc_page_failed; - } - ret = map_kernel_range_noflush((unsigned long)page_addr, - PAGE_SIZE, PAGE_KERNEL, page); - flush_cache_vmap((unsigned long)page_addr, - (unsigned long)page_addr + PAGE_SIZE); - if (ret < 0) { - pr_err("%d: binder_alloc_buf failed to map page at %p in kernel\n", - proc->pid, page_addr); - goto err_map_kernel_failed; - } - user_page_addr = - (uintptr_t)page_addr + proc->user_buffer_offset; - ret = vm_insert_page(vma, user_page_addr, page[0]); - if (ret) { - pr_err("%d: binder_alloc_buf failed to map page at %lx in userspace\n", - proc->pid, user_page_addr); - goto err_vm_insert_page_failed; - } - /* vm_insert_page does not seem to increment the refcount */ - } - if (mm) { -#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) - mmap_write_unlock(mm); -#else - up_write(&mm->mmap_sem); -#endif - mmput(mm); - } - return 0; - -free_range: - for (page_addr = end - PAGE_SIZE; page_addr >= start; - page_addr -= PAGE_SIZE) { - page = &proc->pages[(page_addr - proc->buffer) / PAGE_SIZE]; - if (vma) -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) - zap_page_range(vma, (uintptr_t)page_addr + - proc->user_buffer_offset, PAGE_SIZE); -#else - zap_page_range(vma, (uintptr_t)page_addr + - proc->user_buffer_offset, PAGE_SIZE, NULL); -#endif -err_vm_insert_page_failed: - unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE); -err_map_kernel_failed: - __free_page(*page); - *page = NULL; -err_alloc_page_failed: - ; - } -err_no_vma: - if (mm) { -#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) - mmap_write_unlock(mm); -#else - up_write(&mm->mmap_sem); -#endif - mmput(mm); - } - return -ENOMEM; -} - -static struct binder_buffer *binder_alloc_buf(struct binder_proc *proc, - size_t data_size, - size_t offsets_size, - size_t extra_buffers_size, - int is_async) -{ - struct rb_node *n = proc->free_buffers.rb_node; - struct binder_buffer *buffer; - size_t buffer_size; - struct rb_node *best_fit = NULL; - void *has_page_addr; - void *end_page_addr; - size_t size, data_offsets_size; - - if (proc->vma == NULL) { - pr_err("%d: binder_alloc_buf, no vma\n", - proc->pid); - return NULL; - } - - data_offsets_size = ALIGN(data_size, sizeof(void *)) + - ALIGN(offsets_size, sizeof(void *)); - - if (data_offsets_size < data_size || data_offsets_size < offsets_size) { - binder_user_error("%d: got transaction with invalid size %zd-%zd\n", - proc->pid, data_size, offsets_size); - return NULL; - } - size = data_offsets_size + ALIGN(extra_buffers_size, sizeof(void *)); - if (size < data_offsets_size || size < extra_buffers_size) { - binder_user_error("%d: got transaction with invalid extra_buffers_size %zd\n", - proc->pid, extra_buffers_size); - return NULL; - } - if (is_async && - proc->free_async_space < size + sizeof(struct binder_buffer)) { - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: binder_alloc_buf size %zd failed, no async space left\n", - proc->pid, size); - return NULL; - } - - while (n) { - buffer = rb_entry(n, struct binder_buffer, rb_node); - BUG_ON(!buffer->free); - buffer_size = binder_buffer_size(proc, buffer); - - if (size < buffer_size) { - best_fit = n; - n = n->rb_left; - } else if (size > buffer_size) - n = n->rb_right; - else { - best_fit = n; - break; - } - } - if (best_fit == NULL) { - pr_err("%d: binder_alloc_buf size %zd failed, no address space\n", - proc->pid, size); - return NULL; - } - if (n == NULL) { - buffer = rb_entry(best_fit, struct binder_buffer, rb_node); - buffer_size = binder_buffer_size(proc, buffer); - } - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: binder_alloc_buf size %zd got buffer %p size %zd\n", - proc->pid, size, buffer, buffer_size); - - has_page_addr = - (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK); - if (n == NULL) { - if (size + sizeof(struct binder_buffer) + 4 >= buffer_size) - buffer_size = size; /* no room for other buffers */ - else - buffer_size = size + sizeof(struct binder_buffer); - } - end_page_addr = - (void *)PAGE_ALIGN((uintptr_t)buffer->data + buffer_size); - if (end_page_addr > has_page_addr) - end_page_addr = has_page_addr; - if (binder_update_page_range(proc, 1, - (void *)PAGE_ALIGN((uintptr_t)buffer->data), end_page_addr, NULL)) - return NULL; - - rb_erase(best_fit, &proc->free_buffers); - buffer->free = 0; - binder_insert_allocated_buffer(proc, buffer); - if (buffer_size != size) { - struct binder_buffer *new_buffer = (void *)buffer->data + size; - - list_add(&new_buffer->entry, &buffer->entry); - new_buffer->free = 1; - binder_insert_free_buffer(proc, new_buffer); - } - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: binder_alloc_buf size %zd got %p\n", - proc->pid, size, buffer); - buffer->data_size = data_size; - buffer->offsets_size = offsets_size; - buffer->extra_buffers_size = extra_buffers_size; - buffer->async_transaction = is_async; - if (is_async) { - proc->free_async_space -= size + sizeof(struct binder_buffer); - binder_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, - "%d: binder_alloc_buf size %zd async free %zd\n", - proc->pid, size, proc->free_async_space); - } - - return buffer; -} - -static void *buffer_start_page(struct binder_buffer *buffer) -{ - return (void *)((uintptr_t)buffer & PAGE_MASK); -} - -static void *buffer_end_page(struct binder_buffer *buffer) -{ - return (void *)(((uintptr_t)(buffer + 1) - 1) & PAGE_MASK); -} - -static void binder_delete_free_buffer(struct binder_proc *proc, - struct binder_buffer *buffer) -{ - struct binder_buffer *prev, *next = NULL; - int free_page_end = 1; - int free_page_start = 1; - - BUG_ON(proc->buffers.next == &buffer->entry); - prev = list_entry(buffer->entry.prev, struct binder_buffer, entry); - BUG_ON(!prev->free); - if (buffer_end_page(prev) == buffer_start_page(buffer)) { - free_page_start = 0; - if (buffer_end_page(prev) == buffer_end_page(buffer)) - free_page_end = 0; - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: merge free, buffer %p share page with %p\n", - proc->pid, buffer, prev); - } - - if (!list_is_last(&buffer->entry, &proc->buffers)) { - next = list_entry(buffer->entry.next, - struct binder_buffer, entry); - if (buffer_start_page(next) == buffer_end_page(buffer)) { - free_page_end = 0; - if (buffer_start_page(next) == - buffer_start_page(buffer)) - free_page_start = 0; - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: merge free, buffer %p share page with %p\n", - proc->pid, buffer, prev); - } - } - list_del(&buffer->entry); - if (free_page_start || free_page_end) { - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: merge free, buffer %p do not share page%s%s with %p or %p\n", - proc->pid, buffer, free_page_start ? "" : " end", - free_page_end ? "" : " start", prev, next); - binder_update_page_range(proc, 0, free_page_start ? - buffer_start_page(buffer) : buffer_end_page(buffer), - (free_page_end ? buffer_end_page(buffer) : - buffer_start_page(buffer)) + PAGE_SIZE, NULL); - } -} - -static void binder_free_buf(struct binder_proc *proc, - struct binder_buffer *buffer) -{ - size_t size, buffer_size; - - buffer_size = binder_buffer_size(proc, buffer); - - size = ALIGN(buffer->data_size, sizeof(void *)) + - ALIGN(buffer->offsets_size, sizeof(void *)) + - ALIGN(buffer->extra_buffers_size, sizeof(void *)); - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%d: binder_free_buf %p size %zd buffer_size %zd\n", - proc->pid, buffer, size, buffer_size); - - BUG_ON(buffer->free); - BUG_ON(size > buffer_size); - BUG_ON(buffer->transaction != NULL); - BUG_ON((void *)buffer < proc->buffer); - BUG_ON((void *)buffer > proc->buffer + proc->buffer_size); - - if (buffer->async_transaction) { - proc->free_async_space += size + sizeof(struct binder_buffer); - - binder_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, - "%d: binder_free_buf size %zd async free %zd\n", - proc->pid, size, proc->free_async_space); - } - - binder_update_page_range(proc, 0, - (void *)PAGE_ALIGN((uintptr_t)buffer->data), - (void *)(((uintptr_t)buffer->data + buffer_size) & PAGE_MASK), - NULL); - rb_erase(&buffer->rb_node, &proc->allocated_buffers); - buffer->free = 1; - if (!list_is_last(&buffer->entry, &proc->buffers)) { - struct binder_buffer *next = list_entry(buffer->entry.next, - struct binder_buffer, entry); - - if (next->free) { - rb_erase(&next->rb_node, &proc->free_buffers); - binder_delete_free_buffer(proc, next); - } - } - if (proc->buffers.next != &buffer->entry) { - struct binder_buffer *prev = list_entry(buffer->entry.prev, - struct binder_buffer, entry); - - if (prev->free) { - binder_delete_free_buffer(proc, buffer); - rb_erase(&prev->rb_node, &proc->free_buffers); - buffer = prev; - } - } - binder_insert_free_buffer(proc, buffer); -} - -static struct binder_node *binder_get_node(struct binder_proc *proc, - binder_uintptr_t ptr) +static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc, + binder_uintptr_t ptr) { struct rb_node *n = proc->nodes.rb_node; struct binder_node *node; + assert_spin_locked(&proc->inner_lock); + while (n) { node = rb_entry(n, struct binder_node, rb_node); @@ -967,21 +1050,46 @@ static struct binder_node *binder_get_node(struct binder_proc *proc, n = n->rb_left; else if (ptr > node->ptr) n = n->rb_right; - else + else { + /* + * take an implicit weak reference + * to ensure node stays alive until + * call to binder_put_node() + */ + binder_inc_node_tmpref_ilocked(node); return node; + } } return NULL; } -static struct binder_node *binder_new_node(struct binder_proc *proc, - binder_uintptr_t ptr, - binder_uintptr_t cookie) +static struct binder_node *binder_get_node(struct binder_proc *proc, + binder_uintptr_t ptr) +{ + struct binder_node *node; + + binder_inner_proc_lock(proc); + node = binder_get_node_ilocked(proc, ptr); + binder_inner_proc_unlock(proc); + return node; +} + +static struct binder_node *binder_init_node_ilocked( + struct binder_proc *proc, + struct binder_node *new_node, + struct flat_binder_object *fp) { struct rb_node **p = &proc->nodes.rb_node; struct rb_node *parent = NULL; struct binder_node *node; + binder_uintptr_t ptr = fp ? fp->binder : 0; + binder_uintptr_t cookie = fp ? fp->cookie : 0; + __u32 flags = fp ? fp->flags : 0; + + assert_spin_locked(&proc->inner_lock); while (*p) { + parent = *p; node = rb_entry(parent, struct binder_node, rb_node); @@ -989,33 +1097,75 @@ static struct binder_node *binder_new_node(struct binder_proc *proc, p = &(*p)->rb_left; else if (ptr > node->ptr) p = &(*p)->rb_right; - else - return NULL; + else { + /* + * A matching node is already in + * the rb tree. Abandon the init + * and return it. + */ + binder_inc_node_tmpref_ilocked(node); + return node; + } } - - node = kzalloc(sizeof(*node), GFP_KERNEL); - if (node == NULL) - return NULL; + node = new_node; binder_stats_created(BINDER_STAT_NODE); + node->tmp_refs++; rb_link_node(&node->rb_node, parent, p); rb_insert_color(&node->rb_node, &proc->nodes); - node->debug_id = ++binder_last_id; + node->debug_id = atomic_inc_return(&binder_last_id); node->proc = proc; node->ptr = ptr; node->cookie = cookie; node->work.type = BINDER_WORK_NODE; + node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK; + node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS); + node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX); + spin_lock_init(&node->lock); INIT_LIST_HEAD(&node->work.entry); INIT_LIST_HEAD(&node->async_todo); binder_debug(BINDER_DEBUG_INTERNAL_REFS, "%d:%d node %d u%016llx c%016llx created\n", proc->pid, current->pid, node->debug_id, (u64)node->ptr, (u64)node->cookie); + return node; } -static int binder_inc_node(struct binder_node *node, int strong, int internal, - struct list_head *target_list) +static struct binder_node *binder_new_node(struct binder_proc *proc, + struct flat_binder_object *fp) { + struct binder_node *node; + struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL); + + if (!new_node) + return NULL; + binder_inner_proc_lock(proc); + node = binder_init_node_ilocked(proc, new_node, fp); + binder_inner_proc_unlock(proc); + if (node != new_node) + /* + * The node was already added by another thread + */ + kfree(new_node); + + return node; +} + +static void binder_free_node(struct binder_node *node) +{ + kfree(node); + binder_stats_deleted(BINDER_STAT_NODE); +} + +static int binder_inc_node_nilocked(struct binder_node *node, int strong, + int internal, + struct list_head *target_list) +{ + struct binder_proc *proc = node->proc; + + assert_spin_locked(&node->lock); + if (proc) + assert_spin_locked(&proc->inner_lock); if (strong) { if (internal) { if (target_list == NULL && @@ -1031,8 +1181,12 @@ static int binder_inc_node(struct binder_node *node, int strong, int internal, } else node->local_strong_refs++; if (!node->has_strong_ref && target_list) { - list_del_init(&node->work.entry); - list_add_tail(&node->work.entry, target_list); + struct binder_thread *thread = container_of(target_list, + struct binder_thread, todo); + binder_dequeue_work_ilocked(&node->work); + BUG_ON(&thread->todo != target_list); + binder_enqueue_deferred_thread_work_ilocked(thread, + &node->work); } } else { if (!internal) @@ -1043,58 +1197,176 @@ static int binder_inc_node(struct binder_node *node, int strong, int internal, node->debug_id); return -EINVAL; } - list_add_tail(&node->work.entry, target_list); + /* + * See comment above + */ + binder_enqueue_work_ilocked(&node->work, target_list); } } return 0; } -static int binder_dec_node(struct binder_node *node, int strong, int internal) +static int binder_inc_node(struct binder_node *node, int strong, int internal, + struct list_head *target_list) { + int ret; + + binder_node_inner_lock(node); + ret = binder_inc_node_nilocked(node, strong, internal, target_list); + binder_node_inner_unlock(node); + + return ret; +} + +static bool binder_dec_node_nilocked(struct binder_node *node, + int strong, int internal) +{ + struct binder_proc *proc = node->proc; + + assert_spin_locked(&node->lock); + if (proc) + assert_spin_locked(&proc->inner_lock); if (strong) { if (internal) node->internal_strong_refs--; else node->local_strong_refs--; if (node->local_strong_refs || node->internal_strong_refs) - return 0; + return false; } else { if (!internal) node->local_weak_refs--; - if (node->local_weak_refs || !hlist_empty(&node->refs)) - return 0; + if (node->local_weak_refs || node->tmp_refs || + !hlist_empty(&node->refs)) + return false; } - if (node->proc && (node->has_strong_ref || node->has_weak_ref)) { + + if (proc && (node->has_strong_ref || node->has_weak_ref)) { if (list_empty(&node->work.entry)) { - list_add_tail(&node->work.entry, &node->proc->todo); - wake_up_interruptible(&node->proc->wait); + binder_enqueue_work_ilocked(&node->work, &proc->todo); + binder_wakeup_proc_ilocked(proc); } } else { if (hlist_empty(&node->refs) && !node->local_strong_refs && - !node->local_weak_refs) { - list_del_init(&node->work.entry); - if (node->proc) { - rb_erase(&node->rb_node, &node->proc->nodes); + !node->local_weak_refs && !node->tmp_refs) { + if (proc) { + binder_dequeue_work_ilocked(&node->work); + rb_erase(&node->rb_node, &proc->nodes); binder_debug(BINDER_DEBUG_INTERNAL_REFS, "refless node %d deleted\n", node->debug_id); } else { + BUG_ON(!list_empty(&node->work.entry)); + spin_lock(&binder_dead_nodes_lock); + /* + * tmp_refs could have changed so + * check it again + */ + if (node->tmp_refs) { + spin_unlock(&binder_dead_nodes_lock); + return false; + } hlist_del(&node->dead_node); + spin_unlock(&binder_dead_nodes_lock); binder_debug(BINDER_DEBUG_INTERNAL_REFS, "dead node %d deleted\n", node->debug_id); } - kfree(node); - binder_stats_deleted(BINDER_STAT_NODE); + return true; } } - - return 0; + return false; } +static void binder_dec_node(struct binder_node *node, int strong, int internal) +{ + bool free_node; -static struct binder_ref *binder_get_ref(struct binder_proc *proc, - u32 desc, bool need_strong_ref) + binder_node_inner_lock(node); + free_node = binder_dec_node_nilocked(node, strong, internal); + binder_node_inner_unlock(node); + if (free_node) + binder_free_node(node); +} + +static void binder_inc_node_tmpref_ilocked(struct binder_node *node) +{ + /* + * No call to binder_inc_node() is needed since we + * don't need to inform userspace of any changes to + * tmp_refs + */ + node->tmp_refs++; +} + +/** + * binder_inc_node_tmpref() - take a temporary reference on node + * @node: node to reference + * + * Take reference on node to prevent the node from being freed + * while referenced only by a local variable. The inner lock is + * needed to serialize with the node work on the queue (which + * isn't needed after the node is dead). If the node is dead + * (node->proc is NULL), use binder_dead_nodes_lock to protect + * node->tmp_refs against dead-node-only cases where the node + * lock cannot be acquired (eg traversing the dead node list to + * print nodes) + */ +static void binder_inc_node_tmpref(struct binder_node *node) +{ + binder_node_lock(node); + if (node->proc) + binder_inner_proc_lock(node->proc); + else + spin_lock(&binder_dead_nodes_lock); + binder_inc_node_tmpref_ilocked(node); + if (node->proc) + binder_inner_proc_unlock(node->proc); + else + spin_unlock(&binder_dead_nodes_lock); + binder_node_unlock(node); +} + +/** + * binder_dec_node_tmpref() - remove a temporary reference on node + * @node: node to reference + * + * Release temporary reference on node taken via binder_inc_node_tmpref() + */ +static void binder_dec_node_tmpref(struct binder_node *node) +{ + bool free_node; + + binder_node_inner_lock(node); + if (!node->proc) + spin_lock(&binder_dead_nodes_lock); + else + __acquire(&binder_dead_nodes_lock); + node->tmp_refs--; + BUG_ON(node->tmp_refs < 0); + if (!node->proc) + spin_unlock(&binder_dead_nodes_lock); + else + __release(&binder_dead_nodes_lock); + /* + * Call binder_dec_node() to check if all refcounts are 0 + * and cleanup is needed. Calling with strong=0 and internal=1 + * causes no actual reference to be released in binder_dec_node(). + * If that changes, a change is needed here too. + */ + free_node = binder_dec_node_nilocked(node, 0, 1); + binder_node_inner_unlock(node); + if (free_node) + binder_free_node(node); +} + +static void binder_put_node(struct binder_node *node) +{ + binder_dec_node_tmpref(node); +} + +static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc, + u32 desc, bool need_strong_ref) { struct rb_node *n = proc->refs_by_desc.rb_node; struct binder_ref *ref; @@ -1102,11 +1374,11 @@ static struct binder_ref *binder_get_ref(struct binder_proc *proc, while (n) { ref = rb_entry(n, struct binder_ref, rb_node_desc); - if (desc < ref->desc) { + if (desc < ref->data.desc) { n = n->rb_left; - } else if (desc > ref->desc) { + } else if (desc > ref->data.desc) { n = n->rb_right; - } else if (need_strong_ref && !ref->strong) { + } else if (need_strong_ref && !ref->data.strong) { binder_user_error("tried to use weak ref as strong ref\n"); return NULL; } else { @@ -1116,14 +1388,34 @@ static struct binder_ref *binder_get_ref(struct binder_proc *proc, return NULL; } -static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc, - struct binder_node *node) +/** + * binder_get_ref_for_node_olocked() - get the ref associated with given node + * @proc: binder_proc that owns the ref + * @node: binder_node of target + * @new_ref: newly allocated binder_ref to be initialized or %NULL + * + * Look up the ref for the given node and return it if it exists + * + * If it doesn't exist and the caller provides a newly allocated + * ref, initialize the fields of the newly allocated ref and insert + * into the given proc rb_trees and node refs list. + * + * Return: the ref for node. It is possible that another thread + * allocated/initialized the ref first in which case the + * returned ref would be different than the passed-in + * new_ref. new_ref must be kfree'd by the caller in + * this case. + */ +static struct binder_ref *binder_get_ref_for_node_olocked( + struct binder_proc *proc, + struct binder_node *node, + struct binder_ref *new_ref) { - struct rb_node *n; + struct binder_context *context = proc->context; struct rb_node **p = &proc->refs_by_node.rb_node; struct rb_node *parent = NULL; - struct binder_ref *ref, *new_ref; - struct binder_context *context = proc->context; + struct binder_ref *ref; + struct rb_node *n; while (*p) { parent = *p; @@ -1136,22 +1428,22 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc, else return ref; } - new_ref = kzalloc(sizeof(*ref), GFP_KERNEL); - if (new_ref == NULL) + if (!new_ref) return NULL; + binder_stats_created(BINDER_STAT_REF); - new_ref->debug_id = ++binder_last_id; + new_ref->data.debug_id = atomic_inc_return(&binder_last_id); new_ref->proc = proc; new_ref->node = node; rb_link_node(&new_ref->rb_node_node, parent, p); rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node); - new_ref->desc = (node == context->binder_context_mgr_node) ? 0 : 1; + new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1; for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) { ref = rb_entry(n, struct binder_ref, rb_node_desc); - if (ref->desc > new_ref->desc) + if (ref->data.desc > new_ref->data.desc) break; - new_ref->desc = ref->desc + 1; + new_ref->data.desc = ref->data.desc + 1; } p = &proc->refs_by_desc.rb_node; @@ -1159,123 +1451,461 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc, parent = *p; ref = rb_entry(parent, struct binder_ref, rb_node_desc); - if (new_ref->desc < ref->desc) + if (new_ref->data.desc < ref->data.desc) p = &(*p)->rb_left; - else if (new_ref->desc > ref->desc) + else if (new_ref->data.desc > ref->data.desc) p = &(*p)->rb_right; else BUG(); } rb_link_node(&new_ref->rb_node_desc, parent, p); rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc); - if (node) { - hlist_add_head(&new_ref->node_entry, &node->refs); - binder_debug(BINDER_DEBUG_INTERNAL_REFS, - "%d new ref %d desc %d for node %d\n", - proc->pid, new_ref->debug_id, new_ref->desc, - node->debug_id); - } else { - binder_debug(BINDER_DEBUG_INTERNAL_REFS, - "%d new ref %d desc %d for dead node\n", - proc->pid, new_ref->debug_id, new_ref->desc); - } + binder_node_lock(node); + hlist_add_head(&new_ref->node_entry, &node->refs); + + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d new ref %d desc %d for node %d\n", + proc->pid, new_ref->data.debug_id, new_ref->data.desc, + node->debug_id); + binder_node_unlock(node); return new_ref; } -static void binder_delete_ref(struct binder_ref *ref) +static void binder_cleanup_ref_olocked(struct binder_ref *ref) { + bool delete_node = false; + binder_debug(BINDER_DEBUG_INTERNAL_REFS, "%d delete ref %d desc %d for node %d\n", - ref->proc->pid, ref->debug_id, ref->desc, + ref->proc->pid, ref->data.debug_id, ref->data.desc, ref->node->debug_id); rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc); rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node); - if (ref->strong) - binder_dec_node(ref->node, 1, 1); + + binder_node_inner_lock(ref->node); + if (ref->data.strong) + binder_dec_node_nilocked(ref->node, 1, 1); + hlist_del(&ref->node_entry); - binder_dec_node(ref->node, 0, 1); + delete_node = binder_dec_node_nilocked(ref->node, 0, 1); + binder_node_inner_unlock(ref->node); + /* + * Clear ref->node unless we want the caller to free the node + */ + if (!delete_node) { + /* + * The caller uses ref->node to determine + * whether the node needs to be freed. Clear + * it since the node is still alive. + */ + ref->node = NULL; + } + if (ref->death) { binder_debug(BINDER_DEBUG_DEAD_BINDER, "%d delete ref %d desc %d has death notification\n", - ref->proc->pid, ref->debug_id, ref->desc); - list_del(&ref->death->work.entry); - kfree(ref->death); + ref->proc->pid, ref->data.debug_id, + ref->data.desc); + binder_dequeue_work(ref->proc, &ref->death->work); binder_stats_deleted(BINDER_STAT_DEATH); } - kfree(ref); binder_stats_deleted(BINDER_STAT_REF); } -static int binder_inc_ref(struct binder_ref *ref, int strong, - struct list_head *target_list) +/** + * binder_inc_ref_olocked() - increment the ref for given handle + * @ref: ref to be incremented + * @strong: if true, strong increment, else weak + * @target_list: list to queue node work on + * + * Increment the ref. @ref->proc->outer_lock must be held on entry + * + * Return: 0, if successful, else errno + */ +static int binder_inc_ref_olocked(struct binder_ref *ref, int strong, + struct list_head *target_list) { int ret; if (strong) { - if (ref->strong == 0) { + if (ref->data.strong == 0) { ret = binder_inc_node(ref->node, 1, 1, target_list); if (ret) return ret; } - ref->strong++; + ref->data.strong++; } else { - if (ref->weak == 0) { + if (ref->data.weak == 0) { ret = binder_inc_node(ref->node, 0, 1, target_list); if (ret) return ret; } - ref->weak++; + ref->data.weak++; } return 0; } - -static int binder_dec_ref(struct binder_ref *ref, int strong) +/** + * binder_dec_ref() - dec the ref for given handle + * @ref: ref to be decremented + * @strong: if true, strong decrement, else weak + * + * Decrement the ref. + * + * Return: true if ref is cleaned up and ready to be freed + */ +static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong) { if (strong) { - if (ref->strong == 0) { + if (ref->data.strong == 0) { binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n", - ref->proc->pid, ref->debug_id, - ref->desc, ref->strong, ref->weak); - return -EINVAL; - } - ref->strong--; - if (ref->strong == 0) { - int ret; - - ret = binder_dec_node(ref->node, strong, 1); - if (ret) - return ret; + ref->proc->pid, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak); + return false; } + ref->data.strong--; + if (ref->data.strong == 0) + binder_dec_node(ref->node, strong, 1); } else { - if (ref->weak == 0) { + if (ref->data.weak == 0) { binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n", - ref->proc->pid, ref->debug_id, - ref->desc, ref->strong, ref->weak); - return -EINVAL; + ref->proc->pid, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak); + return false; } - ref->weak--; + ref->data.weak--; } - if (ref->strong == 0 && ref->weak == 0) - binder_delete_ref(ref); - return 0; + if (ref->data.strong == 0 && ref->data.weak == 0) { + binder_cleanup_ref_olocked(ref); + return true; + } + return false; } -static void binder_pop_transaction(struct binder_thread *target_thread, - struct binder_transaction *t) +/** + * binder_get_node_from_ref() - get the node from the given proc/desc + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @need_strong_ref: if true, only return node if ref is strong + * @rdata: the id/refcount data for the ref + * + * Given a proc and ref handle, return the associated binder_node + * + * Return: a binder_node or NULL if not found or not strong when strong required + */ +static struct binder_node *binder_get_node_from_ref( + struct binder_proc *proc, + u32 desc, bool need_strong_ref, + struct binder_ref_data *rdata) { - if (target_thread) { - BUG_ON(target_thread->transaction_stack != t); - BUG_ON(target_thread->transaction_stack->from != target_thread); - target_thread->transaction_stack = - target_thread->transaction_stack->from_parent; - t->from = NULL; + struct binder_node *node; + struct binder_ref *ref; + + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, desc, need_strong_ref); + if (!ref) + goto err_no_ref; + node = ref->node; + /* + * Take an implicit reference on the node to ensure + * it stays alive until the call to binder_put_node() + */ + binder_inc_node_tmpref(node); + if (rdata) + *rdata = ref->data; + binder_proc_unlock(proc); + + return node; + +err_no_ref: + binder_proc_unlock(proc); + return NULL; +} + +/** + * binder_free_ref() - free the binder_ref + * @ref: ref to free + * + * Free the binder_ref. Free the binder_node indicated by ref->node + * (if non-NULL) and the binder_ref_death indicated by ref->death. + */ +static void binder_free_ref(struct binder_ref *ref) +{ + if (ref->node) + binder_free_node(ref->node); + kfree(ref->death); + kfree(ref); +} + +/** + * binder_update_ref_for_handle() - inc/dec the ref for given handle + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @increment: true=inc reference, false=dec reference + * @strong: true=strong reference, false=weak reference + * @rdata: the id/refcount data for the ref + * + * Given a proc and ref handle, increment or decrement the ref + * according to "increment" arg. + * + * Return: 0 if successful, else errno + */ +static int binder_update_ref_for_handle(struct binder_proc *proc, + uint32_t desc, bool increment, bool strong, + struct binder_ref_data *rdata) +{ + int ret = 0; + struct binder_ref *ref; + bool delete_ref = false; + + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, desc, strong); + if (!ref) { + ret = -EINVAL; + goto err_no_ref; } - t->need_reply = 0; - if (t->buffer) - t->buffer->transaction = NULL; + if (increment) + ret = binder_inc_ref_olocked(ref, strong, NULL); + else + delete_ref = binder_dec_ref_olocked(ref, strong); + + if (rdata) + *rdata = ref->data; + binder_proc_unlock(proc); + + if (delete_ref) + binder_free_ref(ref); + return ret; + +err_no_ref: + binder_proc_unlock(proc); + return ret; +} + +/** + * binder_dec_ref_for_handle() - dec the ref for given handle + * @proc: proc containing the ref + * @desc: the handle associated with the ref + * @strong: true=strong reference, false=weak reference + * @rdata: the id/refcount data for the ref + * + * Just calls binder_update_ref_for_handle() to decrement the ref. + * + * Return: 0 if successful, else errno + */ +static int binder_dec_ref_for_handle(struct binder_proc *proc, + uint32_t desc, bool strong, struct binder_ref_data *rdata) +{ + return binder_update_ref_for_handle(proc, desc, false, strong, rdata); +} + + +/** + * binder_inc_ref_for_node() - increment the ref for given proc/node + * @proc: proc containing the ref + * @node: target node + * @strong: true=strong reference, false=weak reference + * @target_list: worklist to use if node is incremented + * @rdata: the id/refcount data for the ref + * + * Given a proc and node, increment the ref. Create the ref if it + * doesn't already exist + * + * Return: 0 if successful, else errno + */ +static int binder_inc_ref_for_node(struct binder_proc *proc, + struct binder_node *node, + bool strong, + struct list_head *target_list, + struct binder_ref_data *rdata) +{ + struct binder_ref *ref; + struct binder_ref *new_ref = NULL; + int ret = 0; + + binder_proc_lock(proc); + ref = binder_get_ref_for_node_olocked(proc, node, NULL); + if (!ref) { + binder_proc_unlock(proc); + new_ref = kzalloc(sizeof(*ref), GFP_KERNEL); + if (!new_ref) + return -ENOMEM; + binder_proc_lock(proc); + ref = binder_get_ref_for_node_olocked(proc, node, new_ref); + } + ret = binder_inc_ref_olocked(ref, strong, target_list); + *rdata = ref->data; + binder_proc_unlock(proc); + if (new_ref && ref != new_ref) + /* + * Another thread created the ref first so + * free the one we allocated + */ + kfree(new_ref); + return ret; +} + +static void binder_pop_transaction_ilocked(struct binder_thread *target_thread, + struct binder_transaction *t) +{ + BUG_ON(!target_thread); + assert_spin_locked(&target_thread->proc->inner_lock); + BUG_ON(target_thread->transaction_stack != t); + BUG_ON(target_thread->transaction_stack->from != target_thread); + target_thread->transaction_stack = + target_thread->transaction_stack->from_parent; + t->from = NULL; +} + +/** + * binder_thread_dec_tmpref() - decrement thread->tmp_ref + * @thread: thread to decrement + * + * A thread needs to be kept alive while being used to create or + * handle a transaction. binder_get_txn_from() is used to safely + * extract t->from from a binder_transaction and keep the thread + * indicated by t->from from being freed. When done with that + * binder_thread, this function is called to decrement the + * tmp_ref and free if appropriate (thread has been released + * and no transaction being processed by the driver) + */ +static void binder_thread_dec_tmpref(struct binder_thread *thread) +{ + /* + * atomic is used to protect the counter value while + * it cannot reach zero or thread->is_dead is false + */ + binder_inner_proc_lock(thread->proc); + atomic_dec(&thread->tmp_ref); + if (thread->is_dead && !atomic_read(&thread->tmp_ref)) { + binder_inner_proc_unlock(thread->proc); + binder_free_thread(thread); + return; + } + binder_inner_proc_unlock(thread->proc); +} + +/** + * binder_proc_dec_tmpref() - decrement proc->tmp_ref + * @proc: proc to decrement + * + * A binder_proc needs to be kept alive while being used to create or + * handle a transaction. proc->tmp_ref is incremented when + * creating a new transaction or the binder_proc is currently in-use + * by threads that are being released. When done with the binder_proc, + * this function is called to decrement the counter and free the + * proc if appropriate (proc has been released, all threads have + * been released and not currenly in-use to process a transaction). + */ +static void binder_proc_dec_tmpref(struct binder_proc *proc) +{ + binder_inner_proc_lock(proc); + proc->tmp_ref--; + if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) && + !proc->tmp_ref) { + binder_inner_proc_unlock(proc); + binder_free_proc(proc); + return; + } + binder_inner_proc_unlock(proc); +} + +/** + * binder_get_txn_from() - safely extract the "from" thread in transaction + * @t: binder transaction for t->from + * + * Atomically return the "from" thread and increment the tmp_ref + * count for the thread to ensure it stays alive until + * binder_thread_dec_tmpref() is called. + * + * Return: the value of t->from + */ +static struct binder_thread *binder_get_txn_from( + struct binder_transaction *t) +{ + struct binder_thread *from; + + spin_lock(&t->lock); + from = t->from; + if (from) + atomic_inc(&from->tmp_ref); + spin_unlock(&t->lock); + return from; +} + +/** + * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock + * @t: binder transaction for t->from + * + * Same as binder_get_txn_from() except it also acquires the proc->inner_lock + * to guarantee that the thread cannot be released while operating on it. + * The caller must call binder_inner_proc_unlock() to release the inner lock + * as well as call binder_dec_thread_txn() to release the reference. + * + * Return: the value of t->from + */ +static struct binder_thread *binder_get_txn_from_and_acq_inner( + struct binder_transaction *t) + __acquires(&t->from->proc->inner_lock) +{ + struct binder_thread *from; + + from = binder_get_txn_from(t); + if (!from) { + __acquire(&from->proc->inner_lock); + return NULL; + } + binder_inner_proc_lock(from->proc); + if (t->from) { + BUG_ON(from != t->from); + return from; + } + binder_inner_proc_unlock(from->proc); + __acquire(&from->proc->inner_lock); + binder_thread_dec_tmpref(from); + return NULL; +} + +/** + * binder_free_txn_fixups() - free unprocessed fd fixups + * @t: binder transaction for t->from + * + * If the transaction is being torn down prior to being + * processed by the target process, free all of the + * fd fixups and fput the file structs. It is safe to + * call this function after the fixups have been + * processed -- in that case, the list will be empty. + */ +static void binder_free_txn_fixups(struct binder_transaction *t) +{ + struct binder_txn_fd_fixup *fixup, *tmp; + + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) { + fput(fixup->file); + list_del(&fixup->fixup_entry); + kfree(fixup); + } +} + +static void binder_free_transaction(struct binder_transaction *t) +{ + struct binder_proc *target_proc = t->to_proc; + + if (target_proc) { + binder_inner_proc_lock(target_proc); + if (t->buffer) + t->buffer->transaction = NULL; + binder_inner_proc_unlock(target_proc); + } + /* + * If the transaction has no target_proc, then + * t->buffer->transaction has already been cleared. + */ + binder_free_txn_fixups(t); kfree(t); binder_stats_deleted(BINDER_STAT_TRANSACTION); } @@ -1288,39 +1918,44 @@ static void binder_send_failed_reply(struct binder_transaction *t, BUG_ON(t->flags & TF_ONE_WAY); while (1) { - target_thread = t->from; + target_thread = binder_get_txn_from_and_acq_inner(t); if (target_thread) { - if (target_thread->return_error != BR_OK && - target_thread->return_error2 == BR_OK) { - target_thread->return_error2 = - target_thread->return_error; - target_thread->return_error = BR_OK; - } - if (target_thread->return_error == BR_OK) { - binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, - "send failed reply for transaction %d to %d:%d\n", - t->debug_id, - target_thread->proc->pid, - target_thread->pid); + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "send failed reply for transaction %d to %d:%d\n", + t->debug_id, + target_thread->proc->pid, + target_thread->pid); - binder_pop_transaction(target_thread, t); - target_thread->return_error = error_code; + binder_pop_transaction_ilocked(target_thread, t); + if (target_thread->reply_error.cmd == BR_OK) { + target_thread->reply_error.cmd = error_code; + binder_enqueue_thread_work_ilocked( + target_thread, + &target_thread->reply_error.work); wake_up_interruptible(&target_thread->wait); } else { - pr_err("reply failed, target thread, %d:%d, has error code %d already\n", - target_thread->proc->pid, - target_thread->pid, - target_thread->return_error); + /* + * Cannot get here for normal operation, but + * we can if multiple synchronous transactions + * are sent without blocking for responses. + * Just ignore the 2nd error in this case. + */ + pr_warn("Unexpected reply error: %u\n", + target_thread->reply_error.cmd); } + binder_inner_proc_unlock(target_thread->proc); + binder_thread_dec_tmpref(target_thread); + binder_free_transaction(t); return; } + __release(&target_thread->proc->inner_lock); next = t->from_parent; binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, "send failed reply for transaction %d, target dead\n", t->debug_id); - binder_pop_transaction(target_thread, t); + binder_free_transaction(t); if (next == NULL) { binder_debug(BINDER_DEBUG_DEAD_BINDER, "reply failed, no target thread at root\n"); @@ -1334,26 +1969,53 @@ static void binder_send_failed_reply(struct binder_transaction *t, } /** - * binder_validate_object() - checks for a valid metadata object in a buffer. + * binder_cleanup_transaction() - cleans up undelivered transaction + * @t: transaction that needs to be cleaned up + * @reason: reason the transaction wasn't delivered + * @error_code: error to return to caller (if synchronous call) + */ +static void binder_cleanup_transaction(struct binder_transaction *t, + const char *reason, + uint32_t error_code) +{ + if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) { + binder_send_failed_reply(t, error_code); + } else { + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered transaction %d, %s\n", + t->debug_id, reason); + binder_free_transaction(t); + } +} + +/** + * binder_get_object() - gets object and checks for valid metadata + * @proc: binder_proc owning the buffer * @buffer: binder_buffer that we're parsing. - * @offset: offset in the buffer at which to validate an object. + * @offset: offset in the @buffer at which to validate an object. + * @object: struct binder_object to read into * * Return: If there's a valid metadata object at @offset in @buffer, the - * size of that object. Otherwise, it returns zero. + * size of that object. Otherwise, it returns zero. The object + * is read into the struct binder_object pointed to by @object. */ -static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset) +static size_t binder_get_object(struct binder_proc *proc, + struct binder_buffer *buffer, + unsigned long offset, + struct binder_object *object) { - /* Check if we can read a header first */ + size_t read_size; struct binder_object_header *hdr; size_t object_size = 0; - if (offset > buffer->data_size - sizeof(*hdr) || - buffer->data_size < sizeof(*hdr) || - !IS_ALIGNED(offset, sizeof(u32))) + read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset); + if (offset > buffer->data_size || read_size < sizeof(*hdr) || + binder_alloc_copy_from_buffer(&proc->alloc, object, buffer, + offset, read_size)) return 0; - /* Ok, now see if we can read a complete object. */ - hdr = (struct binder_object_header *)(buffer->data + offset); + /* Ok, now see if we read a complete object. */ + hdr = &object->hdr; switch (hdr->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: @@ -1382,10 +2044,13 @@ static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset) /** * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer. + * @proc: binder_proc owning the buffer * @b: binder_buffer containing the object + * @object: struct binder_object to read into * @index: index in offset array at which the binder_buffer_object is * located - * @start: points to the start of the offset array + * @start_offset: points to the start of the offset array + * @object_offsetp: offset of @object read from @b * @num_valid: the number of valid offsets in the offset array * * Return: If @index is within the valid range of the offset array @@ -1396,34 +2061,48 @@ static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset) * Note that the offset found in index @index itself is not * verified; this function assumes that @num_valid elements * from @start were previously verified to have valid offsets. + * If @object_offsetp is non-NULL, then the offset within + * @b is written to it. */ -static struct binder_buffer_object *binder_validate_ptr(struct binder_buffer *b, - binder_size_t index, - binder_size_t *start, - binder_size_t num_valid) +static struct binder_buffer_object *binder_validate_ptr( + struct binder_proc *proc, + struct binder_buffer *b, + struct binder_object *object, + binder_size_t index, + binder_size_t start_offset, + binder_size_t *object_offsetp, + binder_size_t num_valid) { - struct binder_buffer_object *buffer_obj; - binder_size_t *offp; + size_t object_size; + binder_size_t object_offset; + unsigned long buffer_offset; if (index >= num_valid) return NULL; - offp = start + index; - buffer_obj = (struct binder_buffer_object *)(b->data + *offp); - if (buffer_obj->hdr.type != BINDER_TYPE_PTR) + buffer_offset = start_offset + sizeof(binder_size_t) * index; + if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset, + b, buffer_offset, + sizeof(object_offset))) return NULL; + object_size = binder_get_object(proc, b, object_offset, object); + if (!object_size || object->hdr.type != BINDER_TYPE_PTR) + return NULL; + if (object_offsetp) + *object_offsetp = object_offset; - return buffer_obj; + return &object->bbo; } /** * binder_validate_fixup() - validates pointer/fd fixups happen in order. + * @proc: binder_proc owning the buffer * @b: transaction buffer - * @objects_start start of objects buffer - * @buffer: binder_buffer_object in which to fix up - * @offset: start offset in @buffer to fix up - * @last_obj: last binder_buffer_object that we fixed up in - * @last_min_offset: minimum fixup offset in @last_obj + * @objects_start_offset: offset to start of objects buffer + * @buffer_obj_offset: offset to binder_buffer_object in which to fix up + * @fixup_offset: start offset in @buffer to fix up + * @last_obj_offset: offset to last binder_buffer_object that we fixed + * @last_min_offset: minimum fixup offset in object at @last_obj_offset * * Return: %true if a fixup in buffer @buffer at offset @offset is * allowed. @@ -1454,63 +2133,145 @@ static struct binder_buffer_object *binder_validate_ptr(struct binder_buffer *b, * C (parent = A, offset = 16) * D (parent = B, offset = 0) // B is not A or any of A's parents */ -static bool binder_validate_fixup(struct binder_buffer *b, - binder_size_t *objects_start, - struct binder_buffer_object *buffer, +static bool binder_validate_fixup(struct binder_proc *proc, + struct binder_buffer *b, + binder_size_t objects_start_offset, + binder_size_t buffer_obj_offset, binder_size_t fixup_offset, - struct binder_buffer_object *last_obj, + binder_size_t last_obj_offset, binder_size_t last_min_offset) { - if (!last_obj) { + if (!last_obj_offset) { /* Nothing to fix up in */ return false; } - while (last_obj != buffer) { + while (last_obj_offset != buffer_obj_offset) { + unsigned long buffer_offset; + struct binder_object last_object; + struct binder_buffer_object *last_bbo; + size_t object_size = binder_get_object(proc, b, last_obj_offset, + &last_object); + if (object_size != sizeof(*last_bbo)) + return false; + + last_bbo = &last_object.bbo; /* * Safe to retrieve the parent of last_obj, since it * was already previously verified by the driver. */ - if ((last_obj->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0) + if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0) + return false; + last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t); + buffer_offset = objects_start_offset + + sizeof(binder_size_t) * last_bbo->parent; + if (binder_alloc_copy_from_buffer(&proc->alloc, + &last_obj_offset, + b, buffer_offset, + sizeof(last_obj_offset))) return false; - last_min_offset = last_obj->parent_offset + sizeof(uintptr_t); - last_obj = (struct binder_buffer_object *) - (b->data + *(objects_start + last_obj->parent)); } return (fixup_offset >= last_min_offset); } +/** + * struct binder_task_work_cb - for deferred close + * + * @twork: callback_head for task work + * @fd: fd to close + * + * Structure to pass task work to be handled after + * returning from binder_ioctl() via task_work_add(). + */ +struct binder_task_work_cb { + struct callback_head twork; + struct file *file; +}; + +/** + * binder_do_fd_close() - close list of file descriptors + * @twork: callback head for task work + * + * It is not safe to call ksys_close() during the binder_ioctl() + * function if there is a chance that binder's own file descriptor + * might be closed. This is to meet the requirements for using + * fdget() (see comments for __fget_light()). Therefore use + * task_work_add() to schedule the close operation once we have + * returned from binder_ioctl(). This function is a callback + * for that mechanism and does the actual ksys_close() on the + * given file descriptor. + */ +static void binder_do_fd_close(struct callback_head *twork) +{ + struct binder_task_work_cb *twcb = container_of(twork, + struct binder_task_work_cb, twork); + + fput(twcb->file); + kfree(twcb); +} + +/** + * binder_deferred_fd_close() - schedule a close for the given file-descriptor + * @fd: file-descriptor to close + * + * See comments in binder_do_fd_close(). This function is used to schedule + * a file-descriptor to be closed after returning from binder_ioctl(). + */ +static void binder_deferred_fd_close(int fd) +{ + struct binder_task_work_cb *twcb; + + twcb = kzalloc(sizeof(*twcb), GFP_KERNEL); + if (!twcb) + return; + init_task_work(&twcb->twork, binder_do_fd_close); + __close_fd_get_file(fd, &twcb->file); + if (twcb->file) { + filp_close(twcb->file, current->files); + task_work_add(current, &twcb->twork, TWA_RESUME); + } else { + kfree(twcb); + } +} + static void binder_transaction_buffer_release(struct binder_proc *proc, struct binder_buffer *buffer, - binder_size_t *failed_at) + binder_size_t failed_at, + bool is_failure) { - binder_size_t *offp, *off_start, *off_end; int debug_id = buffer->debug_id; + binder_size_t off_start_offset, buffer_offset, off_end_offset; binder_debug(BINDER_DEBUG_TRANSACTION, - "%d buffer release %d, size %zd-%zd, failed at %p\n", + "%d buffer release %d, size %zd-%zd, failed at %llx\n", proc->pid, buffer->debug_id, - buffer->data_size, buffer->offsets_size, failed_at); + buffer->data_size, buffer->offsets_size, + (unsigned long long)failed_at); if (buffer->target_node) binder_dec_node(buffer->target_node, 1, 0); - off_start = (binder_size_t *)(buffer->data + - ALIGN(buffer->data_size, sizeof(void *))); - if (failed_at) - off_end = failed_at; - else - off_end = (void *)off_start + buffer->offsets_size; - for (offp = off_start; offp < off_end; offp++) { + off_start_offset = ALIGN(buffer->data_size, sizeof(void *)); + off_end_offset = is_failure ? failed_at : + off_start_offset + buffer->offsets_size; + for (buffer_offset = off_start_offset; buffer_offset < off_end_offset; + buffer_offset += sizeof(binder_size_t)) { struct binder_object_header *hdr; - size_t object_size = binder_validate_object(buffer, *offp); + size_t object_size = 0; + struct binder_object object; + binder_size_t object_offset; + if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset, + buffer, buffer_offset, + sizeof(object_offset))) + object_size = binder_get_object(proc, buffer, + object_offset, &object); if (object_size == 0) { pr_err("transaction release %d bad object at offset %lld, size %zd\n", - debug_id, (u64)*offp, buffer->data_size); + debug_id, (u64)object_offset, buffer->data_size); continue; } - hdr = (struct binder_object_header *)(buffer->data + *offp); + hdr = &object.hdr; switch (hdr->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: { @@ -1529,33 +2290,38 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, node->debug_id, (u64)node->ptr); binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER, 0); + binder_put_node(node); } break; case BINDER_TYPE_HANDLE: case BINDER_TYPE_WEAK_HANDLE: { struct flat_binder_object *fp; - struct binder_ref *ref; + struct binder_ref_data rdata; + int ret; fp = to_flat_binder_object(hdr); - ref = binder_get_ref(proc, fp->handle, - hdr->type == BINDER_TYPE_HANDLE); - if (ref == NULL) { - pr_err("transaction release %d bad handle %d\n", - debug_id, fp->handle); + ret = binder_dec_ref_for_handle(proc, fp->handle, + hdr->type == BINDER_TYPE_HANDLE, &rdata); + + if (ret) { + pr_err("transaction release %d bad handle %d, ret = %d\n", + debug_id, fp->handle, ret); break; } binder_debug(BINDER_DEBUG_TRANSACTION, - " ref %d desc %d (node %d)\n", - ref->debug_id, ref->desc, ref->node->debug_id); - binder_dec_ref(ref, hdr->type == BINDER_TYPE_HANDLE); + " ref %d desc %d\n", + rdata.debug_id, rdata.desc); } break; case BINDER_TYPE_FD: { - struct binder_fd_object *fp = to_binder_fd_object(hdr); - - binder_debug(BINDER_DEBUG_TRANSACTION, - " fd %d\n", fp->fd); - if (failed_at) - task_close_fd(proc, fp->fd); + /* + * No need to close the file here since user-space + * closes it for for successfully delivered + * transactions. For transactions that weren't + * delivered, the new fd was never allocated so + * there is no need to close and the fput on the + * file is done when the transaction is torn + * down. + */ } break; case BINDER_TYPE_PTR: /* @@ -1566,27 +2332,34 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, case BINDER_TYPE_FDA: { struct binder_fd_array_object *fda; struct binder_buffer_object *parent; - uintptr_t parent_buffer; - u32 *fd_array; + struct binder_object ptr_object; + binder_size_t fda_offset; size_t fd_index; binder_size_t fd_buf_size; + binder_size_t num_valid; + if (proc->tsk != current->group_leader) { + /* + * Nothing to do if running in sender context + * The fd fixups have not been applied so no + * fds need to be closed. + */ + continue; + } + + num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); fda = to_binder_fd_array_object(hdr); - parent = binder_validate_ptr(buffer, fda->parent, - off_start, - offp - off_start); + parent = binder_validate_ptr(proc, buffer, &ptr_object, + fda->parent, + off_start_offset, + NULL, + num_valid); if (!parent) { - pr_err("transaction release %d bad parent offset", + pr_err("transaction release %d bad parent offset\n", debug_id); continue; } - /* - * Since the parent was already fixed up, convert it - * back to kernel address space to access it - */ - parent_buffer = parent->buffer - - proc->user_buffer_offset; - fd_buf_size = sizeof(u32) * fda->num_fds; if (fda->num_fds >= SIZE_MAX / sizeof(u32)) { pr_err("transaction release %d invalid number of fds (%lld)\n", @@ -1600,9 +2373,30 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, debug_id, (u64)fda->num_fds); continue; } - fd_array = (u32 *)(parent_buffer + fda->parent_offset); - for (fd_index = 0; fd_index < fda->num_fds; fd_index++) - task_close_fd(proc, fd_array[fd_index]); + /* + * the source data for binder_buffer_object is visible + * to user-space and the @buffer element is the user + * pointer to the buffer_object containing the fd_array. + * Convert the address to an offset relative to + * the base of the transaction buffer. + */ + fda_offset = + (parent->buffer - (uintptr_t)buffer->user_data) + + fda->parent_offset; + for (fd_index = 0; fd_index < fda->num_fds; + fd_index++) { + u32 fd; + int err; + binder_size_t offset = fda_offset + + fd_index * sizeof(fd); + + err = binder_alloc_copy_from_buffer( + &proc->alloc, &fd, buffer, + offset, sizeof(fd)); + WARN_ON(err); + if (!err) + binder_deferred_fd_close(fd); + } } break; default: pr_err("transaction release %d bad object type %x\n", @@ -1617,118 +2411,137 @@ static int binder_translate_binder(struct flat_binder_object *fp, struct binder_thread *thread) { struct binder_node *node; - struct binder_ref *ref; struct binder_proc *proc = thread->proc; struct binder_proc *target_proc = t->to_proc; + struct binder_ref_data rdata; + int ret = 0; node = binder_get_node(proc, fp->binder); if (!node) { - node = binder_new_node(proc, fp->binder, fp->cookie); + node = binder_new_node(proc, fp); if (!node) return -ENOMEM; - - node->min_priority = fp->flags & FLAT_BINDER_FLAG_PRIORITY_MASK; - node->accept_fds = !!(fp->flags & FLAT_BINDER_FLAG_ACCEPTS_FDS); } if (fp->cookie != node->cookie) { binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n", proc->pid, thread->pid, (u64)fp->binder, node->debug_id, (u64)fp->cookie, (u64)node->cookie); - return -EINVAL; + ret = -EINVAL; + goto done; + } + if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) { + ret = -EPERM; + goto done; } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 0, 0) - if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) - return -EPERM; -#endif - ref = binder_get_ref_for_node(target_proc, node); - if (!ref) - return -EINVAL; + ret = binder_inc_ref_for_node(target_proc, node, + fp->hdr.type == BINDER_TYPE_BINDER, + &thread->todo, &rdata); + if (ret) + goto done; if (fp->hdr.type == BINDER_TYPE_BINDER) fp->hdr.type = BINDER_TYPE_HANDLE; else fp->hdr.type = BINDER_TYPE_WEAK_HANDLE; fp->binder = 0; - fp->handle = ref->desc; + fp->handle = rdata.desc; fp->cookie = 0; - binder_inc_ref(ref, fp->hdr.type == BINDER_TYPE_HANDLE, &thread->todo); - trace_binder_transaction_node_to_ref(t, node, ref); + trace_binder_transaction_node_to_ref(t, node, &rdata); binder_debug(BINDER_DEBUG_TRANSACTION, " node %d u%016llx -> ref %d desc %d\n", node->debug_id, (u64)node->ptr, - ref->debug_id, ref->desc); - - return 0; + rdata.debug_id, rdata.desc); +done: + binder_put_node(node); + return ret; } static int binder_translate_handle(struct flat_binder_object *fp, struct binder_transaction *t, struct binder_thread *thread) { - struct binder_ref *ref; struct binder_proc *proc = thread->proc; struct binder_proc *target_proc = t->to_proc; + struct binder_node *node; + struct binder_ref_data src_rdata; + int ret = 0; - ref = binder_get_ref(proc, fp->handle, - fp->hdr.type == BINDER_TYPE_HANDLE); - if (!ref) { + node = binder_get_node_from_ref(proc, fp->handle, + fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata); + if (!node) { binder_user_error("%d:%d got transaction with invalid handle, %d\n", proc->pid, thread->pid, fp->handle); return -EINVAL; } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 0, 0) - if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) - return -EPERM; -#endif + if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) { + ret = -EPERM; + goto done; + } - if (ref->node->proc == target_proc) { + binder_node_lock(node); + if (node->proc == target_proc) { if (fp->hdr.type == BINDER_TYPE_HANDLE) fp->hdr.type = BINDER_TYPE_BINDER; else fp->hdr.type = BINDER_TYPE_WEAK_BINDER; - fp->binder = ref->node->ptr; - fp->cookie = ref->node->cookie; - binder_inc_node(ref->node, fp->hdr.type == BINDER_TYPE_BINDER, - 0, NULL); - trace_binder_transaction_ref_to_node(t, ref); + fp->binder = node->ptr; + fp->cookie = node->cookie; + if (node->proc) + binder_inner_proc_lock(node->proc); + else + __acquire(&node->proc->inner_lock); + binder_inc_node_nilocked(node, + fp->hdr.type == BINDER_TYPE_BINDER, + 0, NULL); + if (node->proc) + binder_inner_proc_unlock(node->proc); + else + __release(&node->proc->inner_lock); + trace_binder_transaction_ref_to_node(t, node, &src_rdata); binder_debug(BINDER_DEBUG_TRANSACTION, " ref %d desc %d -> node %d u%016llx\n", - ref->debug_id, ref->desc, ref->node->debug_id, - (u64)ref->node->ptr); + src_rdata.debug_id, src_rdata.desc, node->debug_id, + (u64)node->ptr); + binder_node_unlock(node); } else { - struct binder_ref *new_ref; + struct binder_ref_data dest_rdata; - new_ref = binder_get_ref_for_node(target_proc, ref->node); - if (!new_ref) - return -EINVAL; + binder_node_unlock(node); + ret = binder_inc_ref_for_node(target_proc, node, + fp->hdr.type == BINDER_TYPE_HANDLE, + NULL, &dest_rdata); + if (ret) + goto done; fp->binder = 0; - fp->handle = new_ref->desc; + fp->handle = dest_rdata.desc; fp->cookie = 0; - binder_inc_ref(new_ref, fp->hdr.type == BINDER_TYPE_HANDLE, - NULL); - trace_binder_transaction_ref_to_ref(t, ref, new_ref); + trace_binder_transaction_ref_to_ref(t, node, &src_rdata, + &dest_rdata); binder_debug(BINDER_DEBUG_TRANSACTION, " ref %d desc %d -> ref %d desc %d (node %d)\n", - ref->debug_id, ref->desc, new_ref->debug_id, - new_ref->desc, ref->node->debug_id); + src_rdata.debug_id, src_rdata.desc, + dest_rdata.debug_id, dest_rdata.desc, + node->debug_id); } - return 0; +done: + binder_put_node(node); + return ret; } -static int binder_translate_fd(int fd, +static int binder_translate_fd(u32 fd, binder_size_t fd_offset, struct binder_transaction *t, struct binder_thread *thread, struct binder_transaction *in_reply_to) { struct binder_proc *proc = thread->proc; struct binder_proc *target_proc = t->to_proc; - int target_fd; + struct binder_txn_fd_fixup *fixup; struct file *file; - int ret; + int ret = 0; bool target_allows_fd; if (in_reply_to) @@ -1751,27 +2564,30 @@ static int binder_translate_fd(int fd, ret = -EBADF; goto err_fget; } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 0, 0) ret = security_binder_transfer_file(proc->tsk, target_proc->tsk, file); if (ret < 0) { ret = -EPERM; goto err_security; } -#endif - target_fd = task_get_unused_fd_flags(target_proc, O_CLOEXEC); - if (target_fd < 0) { + /* + * Add fixup record for this transaction. The allocation + * of the fd in the target needs to be done from a + * target thread. + */ + fixup = kzalloc(sizeof(*fixup), GFP_KERNEL); + if (!fixup) { ret = -ENOMEM; - goto err_get_unused_fd; + goto err_alloc; } - task_fd_install(target_proc, target_fd, file); - trace_binder_transaction_fd(t, fd, target_fd); - binder_debug(BINDER_DEBUG_TRANSACTION, " fd %d -> %d\n", - fd, target_fd); + fixup->file = file; + fixup->offset = fd_offset; + trace_binder_transaction_fd_send(t, fd, fixup->offset); + list_add_tail(&fixup->fixup_entry, &t->fd_fixups); - return target_fd; + return ret; -err_get_unused_fd: +err_alloc: err_security: fput(file); err_fget: @@ -1785,10 +2601,8 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, struct binder_thread *thread, struct binder_transaction *in_reply_to) { - binder_size_t fdi, fd_buf_size, num_installed_fds; - int target_fd; - uintptr_t parent_buffer; - u32 *fd_array; + binder_size_t fdi, fd_buf_size; + binder_size_t fda_offset; struct binder_proc *proc = thread->proc; struct binder_proc *target_proc = t->to_proc; @@ -1806,63 +2620,67 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, return -EINVAL; } /* - * Since the parent was already fixed up, convert it - * back to the kernel address space to access it + * the source data for binder_buffer_object is visible + * to user-space and the @buffer element is the user + * pointer to the buffer_object containing the fd_array. + * Convert the address to an offset relative to + * the base of the transaction buffer. */ - parent_buffer = parent->buffer - target_proc->user_buffer_offset; - fd_array = (u32 *)(parent_buffer + fda->parent_offset); - if (!IS_ALIGNED((unsigned long)fd_array, sizeof(u32))) { + fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) + + fda->parent_offset; + if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32))) { binder_user_error("%d:%d parent offset not aligned correctly.\n", proc->pid, thread->pid); return -EINVAL; } for (fdi = 0; fdi < fda->num_fds; fdi++) { - target_fd = binder_translate_fd(fd_array[fdi], t, thread, - in_reply_to); - if (target_fd < 0) - goto err_translate_fd_failed; - fd_array[fdi] = target_fd; + u32 fd; + int ret; + binder_size_t offset = fda_offset + fdi * sizeof(fd); + + ret = binder_alloc_copy_from_buffer(&target_proc->alloc, + &fd, t->buffer, + offset, sizeof(fd)); + if (!ret) + ret = binder_translate_fd(fd, offset, t, thread, + in_reply_to); + if (ret < 0) + return ret; } return 0; - -err_translate_fd_failed: - /* - * Failed to allocate fd or security error, free fds - * installed so far. - */ - num_installed_fds = fdi; - for (fdi = 0; fdi < num_installed_fds; fdi++) - task_close_fd(target_proc, fd_array[fdi]); - return target_fd; } static int binder_fixup_parent(struct binder_transaction *t, struct binder_thread *thread, struct binder_buffer_object *bp, - binder_size_t *off_start, + binder_size_t off_start_offset, binder_size_t num_valid, - struct binder_buffer_object *last_fixup_obj, + binder_size_t last_fixup_obj_off, binder_size_t last_fixup_min_off) { struct binder_buffer_object *parent; - u8 *parent_buffer; struct binder_buffer *b = t->buffer; struct binder_proc *proc = thread->proc; struct binder_proc *target_proc = t->to_proc; + struct binder_object object; + binder_size_t buffer_offset; + binder_size_t parent_offset; if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT)) return 0; - parent = binder_validate_ptr(b, bp->parent, off_start, num_valid); + parent = binder_validate_ptr(target_proc, b, &object, bp->parent, + off_start_offset, &parent_offset, + num_valid); if (!parent) { binder_user_error("%d:%d got transaction with invalid parent offset or type\n", proc->pid, thread->pid); return -EINVAL; } - if (!binder_validate_fixup(b, off_start, - parent, bp->parent_offset, - last_fixup_obj, + if (!binder_validate_fixup(target_proc, b, off_start_offset, + parent_offset, bp->parent_offset, + last_fixup_obj_off, last_fixup_min_off)) { binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n", proc->pid, thread->pid); @@ -1876,13 +2694,122 @@ static int binder_fixup_parent(struct binder_transaction *t, proc->pid, thread->pid); return -EINVAL; } - parent_buffer = (u8 *)(parent->buffer - - target_proc->user_buffer_offset); - *(binder_uintptr_t *)(parent_buffer + bp->parent_offset) = bp->buffer; + buffer_offset = bp->parent_offset + + (uintptr_t)parent->buffer - (uintptr_t)b->user_data; + if (binder_alloc_copy_to_buffer(&target_proc->alloc, b, buffer_offset, + &bp->buffer, sizeof(bp->buffer))) { + binder_user_error("%d:%d got transaction with invalid parent offset\n", + proc->pid, thread->pid); + return -EINVAL; + } return 0; } +/** + * binder_proc_transaction() - sends a transaction to a process and wakes it up + * @t: transaction to send + * @proc: process to send the transaction to + * @thread: thread in @proc to send the transaction to (may be NULL) + * + * This function queues a transaction to the specified process. It will try + * to find a thread in the target process to handle the transaction and + * wake it up. If no thread is found, the work is queued to the proc + * waitqueue. + * + * If the @thread parameter is not NULL, the transaction is always queued + * to the waitlist of that specific thread. + * + * Return: true if the transactions was successfully queued + * false if the target process or thread is dead + */ +static bool binder_proc_transaction(struct binder_transaction *t, + struct binder_proc *proc, + struct binder_thread *thread) +{ + struct binder_node *node = t->buffer->target_node; + bool oneway = !!(t->flags & TF_ONE_WAY); + bool pending_async = false; + + BUG_ON(!node); + binder_node_lock(node); + if (oneway) { + BUG_ON(thread); + if (node->has_async_transaction) + pending_async = true; + else + node->has_async_transaction = true; + } + + binder_inner_proc_lock(proc); + + if (proc->is_dead || (thread && thread->is_dead)) { + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + return false; + } + + if (!thread && !pending_async) + thread = binder_select_thread_ilocked(proc); + + if (thread) + binder_enqueue_thread_work_ilocked(thread, &t->work); + else if (!pending_async) + binder_enqueue_work_ilocked(&t->work, &proc->todo); + else + binder_enqueue_work_ilocked(&t->work, &node->async_todo); + + if (!pending_async) + binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */); + + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + + return true; +} + +/** + * binder_get_node_refs_for_txn() - Get required refs on node for txn + * @node: struct binder_node for which to get refs + * @proc: returns @node->proc if valid + * @error: if no @proc then returns BR_DEAD_REPLY + * + * User-space normally keeps the node alive when creating a transaction + * since it has a reference to the target. The local strong ref keeps it + * alive if the sending process dies before the target process processes + * the transaction. If the source process is malicious or has a reference + * counting bug, relying on the local strong ref can fail. + * + * Since user-space can cause the local strong ref to go away, we also take + * a tmpref on the node to ensure it survives while we are constructing + * the transaction. We also need a tmpref on the proc while we are + * constructing the transaction, so we take that here as well. + * + * Return: The target_node with refs taken or NULL if no @node->proc is NULL. + * Also sets @proc if valid. If the @node->proc is NULL indicating that the + * target proc has died, @error is set to BR_DEAD_REPLY + */ +static struct binder_node *binder_get_node_refs_for_txn( + struct binder_node *node, + struct binder_proc **procp, + uint32_t *error) +{ + struct binder_node *target_node = NULL; + + binder_node_inner_lock(node); + if (node->proc) { + target_node = node; + binder_inc_node_nilocked(node, 1, 0, NULL); + binder_inc_node_tmpref_ilocked(node); + node->proc->tmp_ref++; + *procp = node->proc; + } else + *error = BR_DEAD_REPLY; + binder_node_inner_unlock(node); + + return target_node; +} + static void binder_transaction(struct binder_proc *proc, struct binder_thread *thread, struct binder_transaction_data *tr, int reply, @@ -1890,55 +2817,74 @@ static void binder_transaction(struct binder_proc *proc, { int ret; struct binder_transaction *t; + struct binder_work *w; struct binder_work *tcomplete; - binder_size_t *offp, *off_end, *off_start; + binder_size_t buffer_offset = 0; + binder_size_t off_start_offset, off_end_offset; binder_size_t off_min; - u8 *sg_bufp, *sg_buf_end; - struct binder_proc *target_proc; + binder_size_t sg_buf_offset, sg_buf_end_offset; + struct binder_proc *target_proc = NULL; struct binder_thread *target_thread = NULL; struct binder_node *target_node = NULL; - struct list_head *target_list; - wait_queue_head_t *target_wait; struct binder_transaction *in_reply_to = NULL; struct binder_transaction_log_entry *e; - uint32_t return_error; - struct binder_buffer_object *last_fixup_obj = NULL; + uint32_t return_error = 0; + uint32_t return_error_param = 0; + uint32_t return_error_line = 0; + binder_size_t last_fixup_obj_off = 0; binder_size_t last_fixup_min_off = 0; struct binder_context *context = proc->context; + int t_debug_id = atomic_inc_return(&binder_last_id); + char *secctx = NULL; + u32 secctx_sz = 0; e = binder_transaction_log_add(&binder_transaction_log); + e->debug_id = t_debug_id; e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY); e->from_proc = proc->pid; e->from_thread = thread->pid; e->target_handle = tr->target.handle; e->data_size = tr->data_size; e->offsets_size = tr->offsets_size; - e->context_name = proc->context->name; + strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME); if (reply) { + binder_inner_proc_lock(proc); in_reply_to = thread->transaction_stack; if (in_reply_to == NULL) { + binder_inner_proc_unlock(proc); binder_user_error("%d:%d got reply transaction with no transaction stack\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; goto err_empty_call_stack; } - binder_set_nice(in_reply_to->saved_priority); if (in_reply_to->to_thread != thread) { + spin_lock(&in_reply_to->lock); binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n", proc->pid, thread->pid, in_reply_to->debug_id, in_reply_to->to_proc ? in_reply_to->to_proc->pid : 0, in_reply_to->to_thread ? in_reply_to->to_thread->pid : 0); + spin_unlock(&in_reply_to->lock); + binder_inner_proc_unlock(proc); return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; in_reply_to = NULL; goto err_bad_call_stack; } thread->transaction_stack = in_reply_to->to_parent; - target_thread = in_reply_to->from; + binder_inner_proc_unlock(proc); + binder_set_nice(in_reply_to->saved_priority); + target_thread = binder_get_txn_from_and_acq_inner(in_reply_to); if (target_thread == NULL) { + /* annotation for sparse */ + __release(&target_thread->proc->inner_lock); return_error = BR_DEAD_REPLY; + return_error_line = __LINE__; goto err_dead_binder; } if (target_thread->transaction_stack != in_reply_to) { @@ -1947,91 +2893,167 @@ static void binder_transaction(struct binder_proc *proc, target_thread->transaction_stack ? target_thread->transaction_stack->debug_id : 0, in_reply_to->debug_id); + binder_inner_proc_unlock(target_thread->proc); return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; in_reply_to = NULL; target_thread = NULL; goto err_dead_binder; } target_proc = target_thread->proc; + target_proc->tmp_ref++; + binder_inner_proc_unlock(target_thread->proc); } else { if (tr->target.handle) { struct binder_ref *ref; - ref = binder_get_ref(proc, tr->target.handle, true); - if (ref == NULL) { + /* + * There must already be a strong ref + * on this node. If so, do a strong + * increment on the node to ensure it + * stays alive until the transaction is + * done. + */ + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, tr->target.handle, + true); + if (ref) { + target_node = binder_get_node_refs_for_txn( + ref->node, &target_proc, + &return_error); + } else { binder_user_error("%d:%d got transaction to invalid handle\n", - proc->pid, thread->pid); + proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + } + binder_proc_unlock(proc); + } else { + mutex_lock(&context->context_mgr_node_lock); + target_node = context->binder_context_mgr_node; + if (target_node) + target_node = binder_get_node_refs_for_txn( + target_node, &target_proc, + &return_error); + else + return_error = BR_DEAD_REPLY; + mutex_unlock(&context->context_mgr_node_lock); + if (target_node && target_proc->pid == proc->pid) { + binder_user_error("%d:%d got transaction to context manager from process owning it\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_invalid_target_handle; } - target_node = ref->node; - } else { - target_node = context->binder_context_mgr_node; - if (target_node == NULL) { - return_error = BR_DEAD_REPLY; - goto err_no_context_mgr_node; - } } - e->to_node = target_node->debug_id; - target_proc = target_node->proc; - if (target_proc == NULL) { - return_error = BR_DEAD_REPLY; + if (!target_node) { + /* + * return_error is set above + */ + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_dead_binder; } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 0, 0) + e->to_node = target_node->debug_id; + if (WARN_ON(proc == target_proc)) { + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_invalid_target_handle; + } if (security_binder_transaction(proc->tsk, target_proc->tsk) < 0) { return_error = BR_FAILED_REPLY; + return_error_param = -EPERM; + return_error_line = __LINE__; goto err_invalid_target_handle; } -#endif + binder_inner_proc_lock(proc); + + w = list_first_entry_or_null(&thread->todo, + struct binder_work, entry); + if (!(tr->flags & TF_ONE_WAY) && w && + w->type == BINDER_WORK_TRANSACTION) { + /* + * Do not allow new outgoing transaction from a + * thread that has a transaction at the head of + * its todo list. Only need to check the head + * because binder_select_thread_ilocked picks a + * thread from proc->waiting_threads to enqueue + * the transaction, and nothing is queued to the + * todo list while the thread is on waiting_threads. + */ + binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n", + proc->pid, thread->pid); + binder_inner_proc_unlock(proc); + return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; + goto err_bad_todo_list; + } + if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) { struct binder_transaction *tmp; tmp = thread->transaction_stack; if (tmp->to_thread != thread) { + spin_lock(&tmp->lock); binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n", proc->pid, thread->pid, tmp->debug_id, tmp->to_proc ? tmp->to_proc->pid : 0, tmp->to_thread ? tmp->to_thread->pid : 0); + spin_unlock(&tmp->lock); + binder_inner_proc_unlock(proc); return_error = BR_FAILED_REPLY; + return_error_param = -EPROTO; + return_error_line = __LINE__; goto err_bad_call_stack; } while (tmp) { - if (tmp->from && tmp->from->proc == target_proc) - target_thread = tmp->from; + struct binder_thread *from; + + spin_lock(&tmp->lock); + from = tmp->from; + if (from && from->proc == target_proc) { + atomic_inc(&from->tmp_ref); + target_thread = from; + spin_unlock(&tmp->lock); + break; + } + spin_unlock(&tmp->lock); tmp = tmp->from_parent; } } + binder_inner_proc_unlock(proc); } - if (target_thread) { + if (target_thread) e->to_thread = target_thread->pid; - target_list = &target_thread->todo; - target_wait = &target_thread->wait; - } else { - target_list = &target_proc->todo; - target_wait = &target_proc->wait; - } e->to_proc = target_proc->pid; /* TODO: reuse incoming transaction for reply */ t = kzalloc(sizeof(*t), GFP_KERNEL); if (t == NULL) { return_error = BR_FAILED_REPLY; + return_error_param = -ENOMEM; + return_error_line = __LINE__; goto err_alloc_t_failed; } + INIT_LIST_HEAD(&t->fd_fixups); binder_stats_created(BINDER_STAT_TRANSACTION); + spin_lock_init(&t->lock); tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL); if (tcomplete == NULL) { return_error = BR_FAILED_REPLY; + return_error_param = -ENOMEM; + return_error_line = __LINE__; goto err_alloc_tcomplete_failed; } binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE); - t->debug_id = ++binder_last_id; - e->debug_id = t->debug_id; + t->debug_id = t_debug_id; if (reply) binder_debug(BINDER_DEBUG_TRANSACTION, @@ -2063,45 +3085,102 @@ static void binder_transaction(struct binder_proc *proc, t->flags = tr->flags; t->priority = task_nice(current); + if (target_node && target_node->txn_security_ctx) { + u32 secid; + size_t added_size; + + security_task_getsecid(proc->tsk, &secid); + ret = security_secid_to_secctx(secid, &secctx, &secctx_sz); + if (ret) { + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_get_secctx_failed; + } + added_size = ALIGN(secctx_sz, sizeof(u64)); + extra_buffers_size += added_size; + if (extra_buffers_size < added_size) { + /* integer overflow of extra_buffers_size */ + return_error = BR_FAILED_REPLY; + return_error_param = EINVAL; + return_error_line = __LINE__; + goto err_bad_extra_size; + } + } + trace_binder_transaction(reply, t, target_node); - t->buffer = binder_alloc_buf(target_proc, tr->data_size, + t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size, tr->offsets_size, extra_buffers_size, - !reply && (t->flags & TF_ONE_WAY)); - if (t->buffer == NULL) { - return_error = BR_FAILED_REPLY; + !reply && (t->flags & TF_ONE_WAY), current->tgid); + if (IS_ERR(t->buffer)) { + /* + * -ESRCH indicates VMA cleared. The target is dying. + */ + return_error_param = PTR_ERR(t->buffer); + return_error = return_error_param == -ESRCH ? + BR_DEAD_REPLY : BR_FAILED_REPLY; + return_error_line = __LINE__; + t->buffer = NULL; goto err_binder_alloc_buf_failed; } - t->buffer->allow_user_free = 0; + if (secctx) { + int err; + size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) + + ALIGN(tr->offsets_size, sizeof(void *)) + + ALIGN(extra_buffers_size, sizeof(void *)) - + ALIGN(secctx_sz, sizeof(u64)); + + t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset; + err = binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, buf_offset, + secctx, secctx_sz); + if (err) { + t->security_ctx = 0; + WARN_ON(1); + } + security_release_secctx(secctx, secctx_sz); + secctx = NULL; + } t->buffer->debug_id = t->debug_id; t->buffer->transaction = t; t->buffer->target_node = target_node; + t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF); trace_binder_transaction_alloc_buf(t->buffer); - if (target_node) - binder_inc_node(target_node, 1, 0, NULL); - off_start = (binder_size_t *)(t->buffer->data + - ALIGN(tr->data_size, sizeof(void *))); - offp = off_start; - - if (copy_from_user(t->buffer->data, (const void __user *)(uintptr_t) - tr->data.ptr.buffer, tr->data_size)) { + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, 0, + (const void __user *) + (uintptr_t)tr->data.ptr.buffer, + tr->data_size)) { binder_user_error("%d:%d got transaction with invalid data ptr\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; goto err_copy_data_failed; } - if (copy_from_user(offp, (const void __user *)(uintptr_t) - tr->data.ptr.offsets, tr->offsets_size)) { + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, + ALIGN(tr->data_size, sizeof(void *)), + (const void __user *) + (uintptr_t)tr->data.ptr.offsets, + tr->offsets_size)) { binder_user_error("%d:%d got transaction with invalid offsets ptr\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; goto err_copy_data_failed; } if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) { binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n", proc->pid, thread->pid, (u64)tr->offsets_size); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_offset; } if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) { @@ -2109,27 +3188,50 @@ static void binder_transaction(struct binder_proc *proc, proc->pid, thread->pid, (u64)extra_buffers_size); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_offset; } - off_end = (void *)off_start + tr->offsets_size; - sg_bufp = (u8 *)(PTR_ALIGN(off_end, sizeof(void *))); - sg_buf_end = sg_bufp + extra_buffers_size; + off_start_offset = ALIGN(tr->data_size, sizeof(void *)); + buffer_offset = off_start_offset; + off_end_offset = off_start_offset + tr->offsets_size; + sg_buf_offset = ALIGN(off_end_offset, sizeof(void *)); + sg_buf_end_offset = sg_buf_offset + extra_buffers_size - + ALIGN(secctx_sz, sizeof(u64)); off_min = 0; - for (; offp < off_end; offp++) { + for (buffer_offset = off_start_offset; buffer_offset < off_end_offset; + buffer_offset += sizeof(binder_size_t)) { struct binder_object_header *hdr; - size_t object_size = binder_validate_object(t->buffer, *offp); + size_t object_size; + struct binder_object object; + binder_size_t object_offset; - if (object_size == 0 || *offp < off_min) { + if (binder_alloc_copy_from_buffer(&target_proc->alloc, + &object_offset, + t->buffer, + buffer_offset, + sizeof(object_offset))) { + return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; + goto err_bad_offset; + } + object_size = binder_get_object(target_proc, t->buffer, + object_offset, &object); + if (object_size == 0 || object_offset < off_min) { binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n", - proc->pid, thread->pid, (u64)*offp, + proc->pid, thread->pid, + (u64)object_offset, (u64)off_min, (u64)t->buffer->data_size); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_offset; } - hdr = (struct binder_object_header *)(t->buffer->data + *offp); - off_min = *offp + object_size; + hdr = &object.hdr; + off_min = object_offset + object_size; switch (hdr->type) { case BINDER_TYPE_BINDER: case BINDER_TYPE_WEAK_BINDER: { @@ -2137,8 +3239,15 @@ static void binder_transaction(struct binder_proc *proc, fp = to_flat_binder_object(hdr); ret = binder_translate_binder(fp, t, thread); - if (ret < 0) { + + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; goto err_translate_failed; } } break; @@ -2148,166 +3257,320 @@ static void binder_transaction(struct binder_proc *proc, fp = to_flat_binder_object(hdr); ret = binder_translate_handle(fp, t, thread); - if (ret < 0) { + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; goto err_translate_failed; } } break; case BINDER_TYPE_FD: { struct binder_fd_object *fp = to_binder_fd_object(hdr); - int target_fd = binder_translate_fd(fp->fd, t, thread, - in_reply_to); + binder_size_t fd_offset = object_offset + + (uintptr_t)&fp->fd - (uintptr_t)fp; + int ret = binder_translate_fd(fp->fd, fd_offset, t, + thread, in_reply_to); - if (target_fd < 0) { + fp->pad_binder = 0; + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fp, sizeof(*fp))) { return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; goto err_translate_failed; } - fp->pad_binder = 0; - fp->fd = target_fd; } break; case BINDER_TYPE_FDA: { + struct binder_object ptr_object; + binder_size_t parent_offset; struct binder_fd_array_object *fda = to_binder_fd_array_object(hdr); + size_t num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); struct binder_buffer_object *parent = - binder_validate_ptr(t->buffer, fda->parent, - off_start, - offp - off_start); + binder_validate_ptr(target_proc, t->buffer, + &ptr_object, fda->parent, + off_start_offset, + &parent_offset, + num_valid); if (!parent) { binder_user_error("%d:%d got transaction with invalid parent offset or type\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_parent; } - if (!binder_validate_fixup(t->buffer, off_start, - parent, fda->parent_offset, - last_fixup_obj, + if (!binder_validate_fixup(target_proc, t->buffer, + off_start_offset, + parent_offset, + fda->parent_offset, + last_fixup_obj_off, last_fixup_min_off)) { binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_parent; } ret = binder_translate_fd_array(fda, parent, t, thread, in_reply_to); if (ret < 0) { return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; goto err_translate_failed; } - last_fixup_obj = parent; + last_fixup_obj_off = parent_offset; last_fixup_min_off = fda->parent_offset + sizeof(u32) * fda->num_fds; } break; case BINDER_TYPE_PTR: { struct binder_buffer_object *bp = to_binder_buffer_object(hdr); - size_t buf_left = sg_buf_end - sg_bufp; + size_t buf_left = sg_buf_end_offset - sg_buf_offset; + size_t num_valid; if (bp->length > buf_left) { binder_user_error("%d:%d got transaction with too large buffer\n", proc->pid, thread->pid); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_offset; } - if (copy_from_user(sg_bufp, - (const void __user *)(uintptr_t) - bp->buffer, bp->length)) { + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, + sg_buf_offset, + (const void __user *) + (uintptr_t)bp->buffer, + bp->length)) { binder_user_error("%d:%d got transaction with invalid offsets ptr\n", proc->pid, thread->pid); + return_error_param = -EFAULT; return_error = BR_FAILED_REPLY; + return_error_line = __LINE__; goto err_copy_data_failed; } /* Fixup buffer pointer to target proc address space */ - bp->buffer = (uintptr_t)sg_bufp + - target_proc->user_buffer_offset; - sg_bufp += ALIGN(bp->length, sizeof(u64)); + bp->buffer = (uintptr_t) + t->buffer->user_data + sg_buf_offset; + sg_buf_offset += ALIGN(bp->length, sizeof(u64)); - ret = binder_fixup_parent(t, thread, bp, off_start, - offp - off_start, - last_fixup_obj, + num_valid = (buffer_offset - off_start_offset) / + sizeof(binder_size_t); + ret = binder_fixup_parent(t, thread, bp, + off_start_offset, + num_valid, + last_fixup_obj_off, last_fixup_min_off); - if (ret < 0) { + if (ret < 0 || + binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + bp, sizeof(*bp))) { return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; goto err_translate_failed; } - last_fixup_obj = bp; + last_fixup_obj_off = object_offset; last_fixup_min_off = 0; } break; default: binder_user_error("%d:%d got transaction with invalid object type, %x\n", proc->pid, thread->pid, hdr->type); return_error = BR_FAILED_REPLY; + return_error_param = -EINVAL; + return_error_line = __LINE__; goto err_bad_object_type; } } + tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; + t->work.type = BINDER_WORK_TRANSACTION; + if (reply) { + binder_enqueue_thread_work(thread, tcomplete); + binder_inner_proc_lock(target_proc); + if (target_thread->is_dead) { + binder_inner_proc_unlock(target_proc); + goto err_dead_proc_or_thread; + } BUG_ON(t->buffer->async_transaction != 0); - binder_pop_transaction(target_thread, in_reply_to); + binder_pop_transaction_ilocked(target_thread, in_reply_to); + binder_enqueue_thread_work_ilocked(target_thread, &t->work); + binder_inner_proc_unlock(target_proc); + wake_up_interruptible_sync(&target_thread->wait); + binder_free_transaction(in_reply_to); } else if (!(t->flags & TF_ONE_WAY)) { BUG_ON(t->buffer->async_transaction != 0); + binder_inner_proc_lock(proc); + /* + * Defer the TRANSACTION_COMPLETE, so we don't return to + * userspace immediately; this allows the target process to + * immediately start processing this transaction, reducing + * latency. We will then return the TRANSACTION_COMPLETE when + * the target replies (or there is an error). + */ + binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete); t->need_reply = 1; t->from_parent = thread->transaction_stack; thread->transaction_stack = t; + binder_inner_proc_unlock(proc); + if (!binder_proc_transaction(t, target_proc, target_thread)) { + binder_inner_proc_lock(proc); + binder_pop_transaction_ilocked(thread, t); + binder_inner_proc_unlock(proc); + goto err_dead_proc_or_thread; + } } else { BUG_ON(target_node == NULL); BUG_ON(t->buffer->async_transaction != 1); - if (target_node->has_async_transaction) { - target_list = &target_node->async_todo; - target_wait = NULL; - } else - target_node->has_async_transaction = 1; - } - t->work.type = BINDER_WORK_TRANSACTION; - list_add_tail(&t->work.entry, target_list); - tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; - list_add_tail(&tcomplete->entry, &thread->todo); - if (target_wait) { - if (reply || !(t->flags & TF_ONE_WAY)) - wake_up_interruptible_sync(target_wait); - else - wake_up_interruptible(target_wait); + binder_enqueue_thread_work(thread, tcomplete); + if (!binder_proc_transaction(t, target_proc, NULL)) + goto err_dead_proc_or_thread; } + if (target_thread) + binder_thread_dec_tmpref(target_thread); + binder_proc_dec_tmpref(target_proc); + if (target_node) + binder_dec_node_tmpref(target_node); + /* + * write barrier to synchronize with initialization + * of log entry + */ + smp_wmb(); + WRITE_ONCE(e->debug_id_done, t_debug_id); return; +err_dead_proc_or_thread: + return_error = BR_DEAD_REPLY; + return_error_line = __LINE__; + binder_dequeue_work(proc, tcomplete); err_translate_failed: err_bad_object_type: err_bad_offset: err_bad_parent: err_copy_data_failed: + binder_free_txn_fixups(t); trace_binder_transaction_failed_buffer_release(t->buffer); - binder_transaction_buffer_release(target_proc, t->buffer, offp); + binder_transaction_buffer_release(target_proc, t->buffer, + buffer_offset, true); + if (target_node) + binder_dec_node_tmpref(target_node); + target_node = NULL; t->buffer->transaction = NULL; - binder_free_buf(target_proc, t->buffer); + binder_alloc_free_buf(&target_proc->alloc, t->buffer); err_binder_alloc_buf_failed: +err_bad_extra_size: + if (secctx) + security_release_secctx(secctx, secctx_sz); +err_get_secctx_failed: kfree(tcomplete); binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); err_alloc_tcomplete_failed: kfree(t); binder_stats_deleted(BINDER_STAT_TRANSACTION); err_alloc_t_failed: +err_bad_todo_list: err_bad_call_stack: err_empty_call_stack: err_dead_binder: err_invalid_target_handle: -err_no_context_mgr_node: + if (target_thread) + binder_thread_dec_tmpref(target_thread); + if (target_proc) + binder_proc_dec_tmpref(target_proc); + if (target_node) { + binder_dec_node(target_node, 1, 0); + binder_dec_node_tmpref(target_node); + } + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, - "%d:%d transaction failed %d, size %lld-%lld\n", - proc->pid, thread->pid, return_error, - (u64)tr->data_size, (u64)tr->offsets_size); + "%d:%d transaction failed %d/%d, size %lld-%lld line %d\n", + proc->pid, thread->pid, return_error, return_error_param, + (u64)tr->data_size, (u64)tr->offsets_size, + return_error_line); { struct binder_transaction_log_entry *fe; + e->return_error = return_error; + e->return_error_param = return_error_param; + e->return_error_line = return_error_line; fe = binder_transaction_log_add(&binder_transaction_log_failed); *fe = *e; + /* + * write barrier to synchronize with initialization + * of log entry + */ + smp_wmb(); + WRITE_ONCE(e->debug_id_done, t_debug_id); + WRITE_ONCE(fe->debug_id_done, t_debug_id); } - BUG_ON(thread->return_error != BR_OK); + BUG_ON(thread->return_error.cmd != BR_OK); if (in_reply_to) { - thread->return_error = BR_TRANSACTION_COMPLETE; + thread->return_error.cmd = BR_TRANSACTION_COMPLETE; + binder_enqueue_thread_work(thread, &thread->return_error.work); binder_send_failed_reply(in_reply_to, return_error); - } else - thread->return_error = return_error; + } else { + thread->return_error.cmd = return_error; + binder_enqueue_thread_work(thread, &thread->return_error.work); + } +} + +/** + * binder_free_buf() - free the specified buffer + * @proc: binder proc that owns buffer + * @buffer: buffer to be freed + * + * If buffer for an async transaction, enqueue the next async + * transaction from the node. + * + * Cleanup buffer and free it. + */ +static void +binder_free_buf(struct binder_proc *proc, struct binder_buffer *buffer) +{ + binder_inner_proc_lock(proc); + if (buffer->transaction) { + buffer->transaction->buffer = NULL; + buffer->transaction = NULL; + } + binder_inner_proc_unlock(proc); + if (buffer->async_transaction && buffer->target_node) { + struct binder_node *buf_node; + struct binder_work *w; + + buf_node = buffer->target_node; + binder_node_inner_lock(buf_node); + BUG_ON(!buf_node->has_async_transaction); + BUG_ON(buf_node->proc != proc); + w = binder_dequeue_work_head_ilocked( + &buf_node->async_todo); + if (!w) { + buf_node->has_async_transaction = false; + } else { + binder_enqueue_work_ilocked( + w, &proc->todo); + binder_wakeup_proc_ilocked(proc); + } + binder_node_inner_unlock(buf_node); + } + trace_binder_transaction_buffer_release(buffer); + binder_transaction_buffer_release(proc, buffer, 0, false); + binder_alloc_free_buf(&proc->alloc, buffer); } static int binder_thread_write(struct binder_proc *proc, @@ -2321,15 +3584,17 @@ static int binder_thread_write(struct binder_proc *proc, void __user *ptr = buffer + *consumed; void __user *end = buffer + size; - while (ptr < end && thread->return_error == BR_OK) { + while (ptr < end && thread->return_error.cmd == BR_OK) { + int ret; + if (get_user(cmd, (uint32_t __user *)ptr)) return -EFAULT; ptr += sizeof(uint32_t); trace_binder_command(cmd); if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) { - binder_stats.bc[_IOC_NR(cmd)]++; - proc->stats.bc[_IOC_NR(cmd)]++; - thread->stats.bc[_IOC_NR(cmd)]++; + atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]); } switch (cmd) { case BC_INCREFS: @@ -2337,53 +3602,68 @@ static int binder_thread_write(struct binder_proc *proc, case BC_RELEASE: case BC_DECREFS: { uint32_t target; - struct binder_ref *ref; const char *debug_string; + bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE; + bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE; + struct binder_ref_data rdata; if (get_user(target, (uint32_t __user *)ptr)) return -EFAULT; + ptr += sizeof(uint32_t); - if (target == 0 && context->binder_context_mgr_node && - (cmd == BC_INCREFS || cmd == BC_ACQUIRE)) { - ref = binder_get_ref_for_node(proc, - context->binder_context_mgr_node); - if (ref->desc != target) { - binder_user_error("%d:%d tried to acquire reference to desc 0, got %d instead\n", - proc->pid, thread->pid, - ref->desc); + ret = -1; + if (increment && !target) { + struct binder_node *ctx_mgr_node; + mutex_lock(&context->context_mgr_node_lock); + ctx_mgr_node = context->binder_context_mgr_node; + if (ctx_mgr_node) { + if (ctx_mgr_node->proc == proc) { + binder_user_error("%d:%d context manager tried to acquire desc 0\n", + proc->pid, thread->pid); + mutex_unlock(&context->context_mgr_node_lock); + return -EINVAL; + } + ret = binder_inc_ref_for_node( + proc, ctx_mgr_node, + strong, NULL, &rdata); } - } else - ref = binder_get_ref(proc, target, - cmd == BC_ACQUIRE || - cmd == BC_RELEASE); - if (ref == NULL) { - binder_user_error("%d:%d refcount change on invalid ref %d\n", - proc->pid, thread->pid, target); - break; + mutex_unlock(&context->context_mgr_node_lock); + } + if (ret) + ret = binder_update_ref_for_handle( + proc, target, increment, strong, + &rdata); + if (!ret && rdata.desc != target) { + binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n", + proc->pid, thread->pid, + target, rdata.desc); } switch (cmd) { case BC_INCREFS: debug_string = "IncRefs"; - binder_inc_ref(ref, 0, NULL); break; case BC_ACQUIRE: debug_string = "Acquire"; - binder_inc_ref(ref, 1, NULL); break; case BC_RELEASE: debug_string = "Release"; - binder_dec_ref(ref, 1); break; case BC_DECREFS: default: debug_string = "DecRefs"; - binder_dec_ref(ref, 0); + break; + } + if (ret) { + binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n", + proc->pid, thread->pid, debug_string, + strong, target, ret); break; } binder_debug(BINDER_DEBUG_USER_REFS, - "%d:%d %s ref %d desc %d s %d w %d for node %d\n", - proc->pid, thread->pid, debug_string, ref->debug_id, - ref->desc, ref->strong, ref->weak, ref->node->debug_id); + "%d:%d %s ref %d desc %d s %d w %d\n", + proc->pid, thread->pid, debug_string, + rdata.debug_id, rdata.desc, rdata.strong, + rdata.weak); break; } case BC_INCREFS_DONE: @@ -2391,6 +3671,7 @@ static int binder_thread_write(struct binder_proc *proc, binder_uintptr_t node_ptr; binder_uintptr_t cookie; struct binder_node *node; + bool free_node; if (get_user(node_ptr, (binder_uintptr_t __user *)ptr)) return -EFAULT; @@ -2415,13 +3696,17 @@ static int binder_thread_write(struct binder_proc *proc, "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE", (u64)node_ptr, node->debug_id, (u64)cookie, (u64)node->cookie); + binder_put_node(node); break; } + binder_node_inner_lock(node); if (cmd == BC_ACQUIRE_DONE) { if (node->pending_strong_ref == 0) { binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n", proc->pid, thread->pid, node->debug_id); + binder_node_inner_unlock(node); + binder_put_node(node); break; } node->pending_strong_ref = 0; @@ -2430,16 +3715,23 @@ static int binder_thread_write(struct binder_proc *proc, binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n", proc->pid, thread->pid, node->debug_id); + binder_node_inner_unlock(node); + binder_put_node(node); break; } node->pending_weak_ref = 0; } - binder_dec_node(node, cmd == BC_ACQUIRE_DONE, 0); + free_node = binder_dec_node_nilocked(node, + cmd == BC_ACQUIRE_DONE, 0); + WARN_ON(free_node); binder_debug(BINDER_DEBUG_USER_REFS, - "%d:%d %s node %d ls %d lw %d\n", + "%d:%d %s node %d ls %d lw %d tr %d\n", proc->pid, thread->pid, cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE", - node->debug_id, node->local_strong_refs, node->local_weak_refs); + node->debug_id, node->local_strong_refs, + node->local_weak_refs, node->tmp_refs); + binder_node_inner_unlock(node); + binder_put_node(node); break; } case BC_ATTEMPT_ACQUIRE: @@ -2457,15 +3749,20 @@ static int binder_thread_write(struct binder_proc *proc, return -EFAULT; ptr += sizeof(binder_uintptr_t); - buffer = binder_buffer_lookup(proc, data_ptr); - if (buffer == NULL) { - binder_user_error("%d:%d BC_FREE_BUFFER u%016llx no match\n", - proc->pid, thread->pid, (u64)data_ptr); - break; - } - if (!buffer->allow_user_free) { - binder_user_error("%d:%d BC_FREE_BUFFER u%016llx matched unreturned buffer\n", - proc->pid, thread->pid, (u64)data_ptr); + buffer = binder_alloc_prepare_to_free(&proc->alloc, + data_ptr); + if (IS_ERR_OR_NULL(buffer)) { + if (PTR_ERR(buffer) == -EPERM) { + binder_user_error( + "%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n", + proc->pid, thread->pid, + (u64)data_ptr); + } else { + binder_user_error( + "%d:%d BC_FREE_BUFFER u%016llx no match\n", + proc->pid, thread->pid, + (u64)data_ptr); + } break; } binder_debug(BINDER_DEBUG_FREE_BUFFER, @@ -2473,20 +3770,6 @@ static int binder_thread_write(struct binder_proc *proc, proc->pid, thread->pid, (u64)data_ptr, buffer->debug_id, buffer->transaction ? "active" : "finished"); - - if (buffer->transaction) { - buffer->transaction->buffer = NULL; - buffer->transaction = NULL; - } - if (buffer->async_transaction && buffer->target_node) { - BUG_ON(!buffer->target_node->has_async_transaction); - if (list_empty(&buffer->target_node->async_todo)) - buffer->target_node->has_async_transaction = 0; - else - list_move_tail(buffer->target_node->async_todo.next, &thread->todo); - } - trace_binder_transaction_buffer_release(buffer); - binder_transaction_buffer_release(proc, buffer, NULL); binder_free_buf(proc, buffer); break; } @@ -2518,6 +3801,7 @@ static int binder_thread_write(struct binder_proc *proc, binder_debug(BINDER_DEBUG_THREADS, "%d:%d BC_REGISTER_LOOPER\n", proc->pid, thread->pid); + binder_inner_proc_lock(proc); if (thread->looper & BINDER_LOOPER_STATE_ENTERED) { thread->looper |= BINDER_LOOPER_STATE_INVALID; binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n", @@ -2531,6 +3815,7 @@ static int binder_thread_write(struct binder_proc *proc, proc->requested_threads_started++; } thread->looper |= BINDER_LOOPER_STATE_REGISTERED; + binder_inner_proc_unlock(proc); break; case BC_ENTER_LOOPER: binder_debug(BINDER_DEBUG_THREADS, @@ -2555,7 +3840,7 @@ static int binder_thread_write(struct binder_proc *proc, uint32_t target; binder_uintptr_t cookie; struct binder_ref *ref; - struct binder_ref_death *death; + struct binder_ref_death *death = NULL; if (get_user(target, (uint32_t __user *)ptr)) return -EFAULT; @@ -2563,7 +3848,28 @@ static int binder_thread_write(struct binder_proc *proc, if (get_user(cookie, (binder_uintptr_t __user *)ptr)) return -EFAULT; ptr += sizeof(binder_uintptr_t); - ref = binder_get_ref(proc, target, false); + if (cmd == BC_REQUEST_DEATH_NOTIFICATION) { + /* + * Allocate memory for death notification + * before taking lock + */ + death = kzalloc(sizeof(*death), GFP_KERNEL); + if (death == NULL) { + WARN_ON(thread->return_error.cmd != + BR_OK); + thread->return_error.cmd = BR_ERROR; + binder_enqueue_thread_work( + thread, + &thread->return_error.work); + binder_debug( + BINDER_DEBUG_FAILED_TRANSACTION, + "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n", + proc->pid, thread->pid); + break; + } + } + binder_proc_lock(proc); + ref = binder_get_ref_olocked(proc, target, false); if (ref == NULL) { binder_user_error("%d:%d %s invalid ref %d\n", proc->pid, thread->pid, @@ -2571,6 +3877,8 @@ static int binder_thread_write(struct binder_proc *proc, "BC_REQUEST_DEATH_NOTIFICATION" : "BC_CLEAR_DEATH_NOTIFICATION", target); + binder_proc_unlock(proc); + kfree(death); break; } @@ -2580,21 +3888,18 @@ static int binder_thread_write(struct binder_proc *proc, cmd == BC_REQUEST_DEATH_NOTIFICATION ? "BC_REQUEST_DEATH_NOTIFICATION" : "BC_CLEAR_DEATH_NOTIFICATION", - (u64)cookie, ref->debug_id, ref->desc, - ref->strong, ref->weak, ref->node->debug_id); + (u64)cookie, ref->data.debug_id, + ref->data.desc, ref->data.strong, + ref->data.weak, ref->node->debug_id); + binder_node_lock(ref->node); if (cmd == BC_REQUEST_DEATH_NOTIFICATION) { if (ref->death) { binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n", proc->pid, thread->pid); - break; - } - death = kzalloc(sizeof(*death), GFP_KERNEL); - if (death == NULL) { - thread->return_error = BR_ERROR; - binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, - "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n", - proc->pid, thread->pid); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); + kfree(death); break; } binder_stats_created(BINDER_STAT_DEATH); @@ -2603,17 +3908,19 @@ static int binder_thread_write(struct binder_proc *proc, ref->death = death; if (ref->node->proc == NULL) { ref->death->work.type = BINDER_WORK_DEAD_BINDER; - if (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) { - list_add_tail(&ref->death->work.entry, &thread->todo); - } else { - list_add_tail(&ref->death->work.entry, &proc->todo); - wake_up_interruptible(&proc->wait); - } + + binder_inner_proc_lock(proc); + binder_enqueue_work_ilocked( + &ref->death->work, &proc->todo); + binder_wakeup_proc_ilocked(proc); + binder_inner_proc_unlock(proc); } } else { if (ref->death == NULL) { binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n", proc->pid, thread->pid); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); break; } death = ref->death; @@ -2622,22 +3929,35 @@ static int binder_thread_write(struct binder_proc *proc, proc->pid, thread->pid, (u64)death->cookie, (u64)cookie); + binder_node_unlock(ref->node); + binder_proc_unlock(proc); break; } ref->death = NULL; + binder_inner_proc_lock(proc); if (list_empty(&death->work.entry)) { death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION; - if (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) { - list_add_tail(&death->work.entry, &thread->todo); - } else { - list_add_tail(&death->work.entry, &proc->todo); - wake_up_interruptible(&proc->wait); + if (thread->looper & + (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED)) + binder_enqueue_thread_work_ilocked( + thread, + &death->work); + else { + binder_enqueue_work_ilocked( + &death->work, + &proc->todo); + binder_wakeup_proc_ilocked( + proc); } } else { BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER); death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR; } + binder_inner_proc_unlock(proc); } + binder_node_unlock(ref->node); + binder_proc_unlock(proc); } break; case BC_DEAD_BINDER_DONE: { struct binder_work *w; @@ -2648,8 +3968,13 @@ static int binder_thread_write(struct binder_proc *proc, return -EFAULT; ptr += sizeof(cookie); - list_for_each_entry(w, &proc->delivered_death, entry) { - struct binder_ref_death *tmp_death = container_of(w, struct binder_ref_death, work); + binder_inner_proc_lock(proc); + list_for_each_entry(w, &proc->delivered_death, + entry) { + struct binder_ref_death *tmp_death = + container_of(w, + struct binder_ref_death, + work); if (tmp_death->cookie == cookie) { death = tmp_death; @@ -2657,25 +3982,31 @@ static int binder_thread_write(struct binder_proc *proc, } } binder_debug(BINDER_DEBUG_DEAD_BINDER, - "%d:%d BC_DEAD_BINDER_DONE %016llx found %p\n", + "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n", proc->pid, thread->pid, (u64)cookie, death); if (death == NULL) { binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n", proc->pid, thread->pid, (u64)cookie); + binder_inner_proc_unlock(proc); break; } - - list_del_init(&death->work.entry); + binder_dequeue_work_ilocked(&death->work); if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) { death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION; - if (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) { - list_add_tail(&death->work.entry, &thread->todo); - } else { - list_add_tail(&death->work.entry, &proc->todo); - wake_up_interruptible(&proc->wait); + if (thread->looper & + (BINDER_LOOPER_STATE_REGISTERED | + BINDER_LOOPER_STATE_ENTERED)) + binder_enqueue_thread_work_ilocked( + thread, &death->work); + else { + binder_enqueue_work_ilocked( + &death->work, + &proc->todo); + binder_wakeup_proc_ilocked(proc); } } + binder_inner_proc_unlock(proc); } break; default: @@ -2693,23 +4024,138 @@ static void binder_stat_br(struct binder_proc *proc, { trace_binder_return(cmd); if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) { - binder_stats.br[_IOC_NR(cmd)]++; - proc->stats.br[_IOC_NR(cmd)]++; - thread->stats.br[_IOC_NR(cmd)]++; + atomic_inc(&binder_stats.br[_IOC_NR(cmd)]); + atomic_inc(&proc->stats.br[_IOC_NR(cmd)]); + atomic_inc(&thread->stats.br[_IOC_NR(cmd)]); } } -static int binder_has_proc_work(struct binder_proc *proc, - struct binder_thread *thread) +static int binder_put_node_cmd(struct binder_proc *proc, + struct binder_thread *thread, + void __user **ptrp, + binder_uintptr_t node_ptr, + binder_uintptr_t node_cookie, + int node_debug_id, + uint32_t cmd, const char *cmd_name) { - return !list_empty(&proc->todo) || - (thread->looper & BINDER_LOOPER_STATE_NEED_RETURN); + void __user *ptr = *ptrp; + + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + + if (put_user(node_ptr, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + + if (put_user(node_cookie, (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + + binder_stat_br(proc, thread, cmd); + binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n", + proc->pid, thread->pid, cmd_name, node_debug_id, + (u64)node_ptr, (u64)node_cookie); + + *ptrp = ptr; + return 0; } -static int binder_has_thread_work(struct binder_thread *thread) +static int binder_wait_for_work(struct binder_thread *thread, + bool do_proc_work) { - return !list_empty(&thread->todo) || thread->return_error != BR_OK || - (thread->looper & BINDER_LOOPER_STATE_NEED_RETURN); + DEFINE_WAIT(wait); + struct binder_proc *proc = thread->proc; + int ret = 0; + + freezer_do_not_count(); + binder_inner_proc_lock(proc); + for (;;) { + prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE); + if (binder_has_work_ilocked(thread, do_proc_work)) + break; + if (do_proc_work) + list_add(&thread->waiting_thread_node, + &proc->waiting_threads); + binder_inner_proc_unlock(proc); + schedule(); + binder_inner_proc_lock(proc); + list_del_init(&thread->waiting_thread_node); + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + } + finish_wait(&thread->wait, &wait); + binder_inner_proc_unlock(proc); + freezer_count(); + + return ret; +} + +/** + * binder_apply_fd_fixups() - finish fd translation + * @proc: binder_proc associated @t->buffer + * @t: binder transaction with list of fd fixups + * + * Now that we are in the context of the transaction target + * process, we can allocate and install fds. Process the + * list of fds to translate and fixup the buffer with the + * new fds. + * + * If we fail to allocate an fd, then free the resources by + * fput'ing files that have not been processed and ksys_close'ing + * any fds that have already been allocated. + */ +static int binder_apply_fd_fixups(struct binder_proc *proc, + struct binder_transaction *t) +{ + struct binder_txn_fd_fixup *fixup, *tmp; + int ret = 0; + + list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) { + int fd = get_unused_fd_flags(O_CLOEXEC); + + if (fd < 0) { + binder_debug(BINDER_DEBUG_TRANSACTION, + "failed fd fixup txn %d fd %d\n", + t->debug_id, fd); + ret = -ENOMEM; + break; + } + binder_debug(BINDER_DEBUG_TRANSACTION, + "fd fixup txn %d fd %d\n", + t->debug_id, fd); + trace_binder_transaction_fd_recv(t, fd, fixup->offset); + fd_install(fd, fixup->file); + fixup->file = NULL; + if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer, + fixup->offset, &fd, + sizeof(u32))) { + ret = -EINVAL; + break; + } + } + list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) { + if (fixup->file) { + fput(fixup->file); + } else if (ret) { + u32 fd; + int err; + + err = binder_alloc_copy_from_buffer(&proc->alloc, &fd, + t->buffer, + fixup->offset, + sizeof(fd)); + WARN_ON(err); + if (!err) + binder_deferred_fd_close(fd); + } + list_del(&fixup->fixup_entry); + kfree(fixup); + } + + return ret; } static int binder_thread_read(struct binder_proc *proc, @@ -2731,37 +4177,15 @@ static int binder_thread_read(struct binder_proc *proc, } retry: - wait_for_proc_work = thread->transaction_stack == NULL && - list_empty(&thread->todo); - - if (thread->return_error != BR_OK && ptr < end) { - if (thread->return_error2 != BR_OK) { - if (put_user(thread->return_error2, (uint32_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(uint32_t); - binder_stat_br(proc, thread, thread->return_error2); - if (ptr == end) - goto done; - thread->return_error2 = BR_OK; - } - if (put_user(thread->return_error, (uint32_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(uint32_t); - binder_stat_br(proc, thread, thread->return_error); - thread->return_error = BR_OK; - goto done; - } - + binder_inner_proc_lock(proc); + wait_for_proc_work = binder_available_for_proc_work_ilocked(thread); + binder_inner_proc_unlock(proc); thread->looper |= BINDER_LOOPER_STATE_WAITING; - if (wait_for_proc_work) - proc->ready_threads++; - - binder_unlock(__func__); trace_binder_wait_for_work(wait_for_proc_work, !!thread->transaction_stack, - !list_empty(&thread->todo)); + !binder_worklist_empty(proc, &thread->todo)); if (wait_for_proc_work) { if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED))) { @@ -2771,23 +4195,15 @@ retry: binder_stop_on_user_error < 2); } binder_set_nice(proc->default_priority); - if (non_block) { - if (!binder_has_proc_work(proc, thread)) - ret = -EAGAIN; - } else - ret = wait_event_freezable_exclusive(proc->wait, binder_has_proc_work(proc, thread)); - } else { - if (non_block) { - if (!binder_has_thread_work(thread)) - ret = -EAGAIN; - } else - ret = wait_event_freezable(thread->wait, binder_has_thread_work(thread)); } - binder_lock(__func__); + if (non_block) { + if (!binder_has_work(thread, wait_for_proc_work)) + ret = -EAGAIN; + } else { + ret = binder_wait_for_work(thread, wait_for_proc_work); + } - if (wait_for_proc_work) - proc->ready_threads--; thread->looper &= ~BINDER_LOOPER_STATE_WAITING; if (ret) @@ -2795,33 +4211,61 @@ retry: while (1) { uint32_t cmd; - struct binder_transaction_data tr; - struct binder_work *w; + struct binder_transaction_data_secctx tr; + struct binder_transaction_data *trd = &tr.transaction_data; + struct binder_work *w = NULL; + struct list_head *list = NULL; struct binder_transaction *t = NULL; + struct binder_thread *t_from; + size_t trsize = sizeof(*trd); + + binder_inner_proc_lock(proc); + if (!binder_worklist_empty_ilocked(&thread->todo)) + list = &thread->todo; + else if (!binder_worklist_empty_ilocked(&proc->todo) && + wait_for_proc_work) + list = &proc->todo; + else { + binder_inner_proc_unlock(proc); - if (!list_empty(&thread->todo)) { - w = list_first_entry(&thread->todo, struct binder_work, - entry); - } else if (!list_empty(&proc->todo) && wait_for_proc_work) { - w = list_first_entry(&proc->todo, struct binder_work, - entry); - } else { /* no data added */ - if (ptr - buffer == 4 && - !(thread->looper & BINDER_LOOPER_STATE_NEED_RETURN)) + if (ptr - buffer == 4 && !thread->looper_need_return) goto retry; break; } - if (end - ptr < sizeof(tr) + 4) + if (end - ptr < sizeof(tr) + 4) { + binder_inner_proc_unlock(proc); break; + } + w = binder_dequeue_work_head_ilocked(list); + if (binder_worklist_empty_ilocked(&thread->todo)) + thread->process_todo = false; switch (w->type) { case BINDER_WORK_TRANSACTION: { + binder_inner_proc_unlock(proc); t = container_of(w, struct binder_transaction, work); } break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + WARN_ON(e->cmd == BR_OK); + binder_inner_proc_unlock(proc); + if (put_user(e->cmd, (uint32_t __user *)ptr)) + return -EFAULT; + cmd = e->cmd; + e->cmd = BR_OK; + ptr += sizeof(uint32_t); + + binder_stat_br(proc, thread, cmd); + } break; case BINDER_WORK_TRANSACTION_COMPLETE: { + binder_inner_proc_unlock(proc); cmd = BR_TRANSACTION_COMPLETE; + kfree(w); + binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); if (put_user(cmd, (uint32_t __user *)ptr)) return -EFAULT; ptr += sizeof(uint32_t); @@ -2830,116 +4274,140 @@ retry: binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE, "%d:%d BR_TRANSACTION_COMPLETE\n", proc->pid, thread->pid); - - list_del(&w->entry); - kfree(w); - binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE); } break; case BINDER_WORK_NODE: { struct binder_node *node = container_of(w, struct binder_node, work); - uint32_t cmd = BR_NOOP; - const char *cmd_name; - int strong = node->internal_strong_refs || node->local_strong_refs; - int weak = !hlist_empty(&node->refs) || node->local_weak_refs || strong; + int strong, weak; + binder_uintptr_t node_ptr = node->ptr; + binder_uintptr_t node_cookie = node->cookie; + int node_debug_id = node->debug_id; + int has_weak_ref; + int has_strong_ref; + void __user *orig_ptr = ptr; - if (weak && !node->has_weak_ref) { - cmd = BR_INCREFS; - cmd_name = "BR_INCREFS"; + BUG_ON(proc != node->proc); + strong = node->internal_strong_refs || + node->local_strong_refs; + weak = !hlist_empty(&node->refs) || + node->local_weak_refs || + node->tmp_refs || strong; + has_strong_ref = node->has_strong_ref; + has_weak_ref = node->has_weak_ref; + + if (weak && !has_weak_ref) { node->has_weak_ref = 1; node->pending_weak_ref = 1; node->local_weak_refs++; - } else if (strong && !node->has_strong_ref) { - cmd = BR_ACQUIRE; - cmd_name = "BR_ACQUIRE"; + } + if (strong && !has_strong_ref) { node->has_strong_ref = 1; node->pending_strong_ref = 1; node->local_strong_refs++; - } else if (!strong && node->has_strong_ref) { - cmd = BR_RELEASE; - cmd_name = "BR_RELEASE"; + } + if (!strong && has_strong_ref) node->has_strong_ref = 0; - } else if (!weak && node->has_weak_ref) { - cmd = BR_DECREFS; - cmd_name = "BR_DECREFS"; + if (!weak && has_weak_ref) node->has_weak_ref = 0; - } - if (cmd != BR_NOOP) { - if (put_user(cmd, (uint32_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(uint32_t); - if (put_user(node->ptr, - (binder_uintptr_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(binder_uintptr_t); - if (put_user(node->cookie, - (binder_uintptr_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(binder_uintptr_t); + if (!weak && !strong) { + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d:%d node %d u%016llx c%016llx deleted\n", + proc->pid, thread->pid, + node_debug_id, + (u64)node_ptr, + (u64)node_cookie); + rb_erase(&node->rb_node, &proc->nodes); + binder_inner_proc_unlock(proc); + binder_node_lock(node); + /* + * Acquire the node lock before freeing the + * node to serialize with other threads that + * may have been holding the node lock while + * decrementing this node (avoids race where + * this thread frees while the other thread + * is unlocking the node after the final + * decrement) + */ + binder_node_unlock(node); + binder_free_node(node); + } else + binder_inner_proc_unlock(proc); - binder_stat_br(proc, thread, cmd); - binder_debug(BINDER_DEBUG_USER_REFS, - "%d:%d %s %d u%016llx c%016llx\n", - proc->pid, thread->pid, cmd_name, - node->debug_id, - (u64)node->ptr, (u64)node->cookie); - } else { - list_del_init(&w->entry); - if (!weak && !strong) { - binder_debug(BINDER_DEBUG_INTERNAL_REFS, - "%d:%d node %d u%016llx c%016llx deleted\n", - proc->pid, thread->pid, - node->debug_id, - (u64)node->ptr, - (u64)node->cookie); - rb_erase(&node->rb_node, &proc->nodes); - kfree(node); - binder_stats_deleted(BINDER_STAT_NODE); - } else { - binder_debug(BINDER_DEBUG_INTERNAL_REFS, - "%d:%d node %d u%016llx c%016llx state unchanged\n", - proc->pid, thread->pid, - node->debug_id, - (u64)node->ptr, - (u64)node->cookie); - } - } + if (weak && !has_weak_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_INCREFS, "BR_INCREFS"); + if (!ret && strong && !has_strong_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_ACQUIRE, "BR_ACQUIRE"); + if (!ret && !strong && has_strong_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_RELEASE, "BR_RELEASE"); + if (!ret && !weak && has_weak_ref) + ret = binder_put_node_cmd( + proc, thread, &ptr, node_ptr, + node_cookie, node_debug_id, + BR_DECREFS, "BR_DECREFS"); + if (orig_ptr == ptr) + binder_debug(BINDER_DEBUG_INTERNAL_REFS, + "%d:%d node %d u%016llx c%016llx state unchanged\n", + proc->pid, thread->pid, + node_debug_id, + (u64)node_ptr, + (u64)node_cookie); + if (ret) + return ret; } break; case BINDER_WORK_DEAD_BINDER: case BINDER_WORK_DEAD_BINDER_AND_CLEAR: case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: { struct binder_ref_death *death; uint32_t cmd; + binder_uintptr_t cookie; death = container_of(w, struct binder_ref_death, work); if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE; else cmd = BR_DEAD_BINDER; - if (put_user(cmd, (uint32_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(uint32_t); - if (put_user(death->cookie, - (binder_uintptr_t __user *)ptr)) - return -EFAULT; - ptr += sizeof(binder_uintptr_t); - binder_stat_br(proc, thread, cmd); + cookie = death->cookie; + binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION, "%d:%d %s %016llx\n", proc->pid, thread->pid, cmd == BR_DEAD_BINDER ? "BR_DEAD_BINDER" : "BR_CLEAR_DEATH_NOTIFICATION_DONE", - (u64)death->cookie); - + (u64)cookie); if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) { - list_del(&w->entry); + binder_inner_proc_unlock(proc); kfree(death); binder_stats_deleted(BINDER_STAT_DEATH); - } else - list_move(&w->entry, &proc->delivered_death); + } else { + binder_enqueue_work_ilocked( + w, &proc->delivered_death); + binder_inner_proc_unlock(proc); + } + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + if (put_user(cookie, + (binder_uintptr_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(binder_uintptr_t); + binder_stat_br(proc, thread, cmd); if (cmd == BR_DEAD_BINDER) goto done; /* DEAD_BINDER notifications can cause transactions */ } break; + default: + binder_inner_proc_unlock(proc); + pr_err("%d:%d: bad work type %d\n", + proc->pid, thread->pid, w->type); + break; } if (!t) @@ -2949,8 +4417,8 @@ retry: if (t->buffer->target_node) { struct binder_node *target_node = t->buffer->target_node; - tr.target.ptr = target_node->ptr; - tr.cookie = target_node->cookie; + trd->target.ptr = target_node->ptr; + trd->cookie = target_node->cookie; t->saved_priority = task_nice(current); if (t->priority < target_node->min_priority && !(t->flags & TF_ONE_WAY)) @@ -2960,38 +4428,85 @@ retry: binder_set_nice(target_node->min_priority); cmd = BR_TRANSACTION; } else { - tr.target.ptr = 0; - tr.cookie = 0; + trd->target.ptr = 0; + trd->cookie = 0; cmd = BR_REPLY; } - tr.code = t->code; - tr.flags = t->flags; - tr.sender_euid = from_kuid(current_user_ns(), t->sender_euid); + trd->code = t->code; + trd->flags = t->flags; + trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid); - if (t->from) { - struct task_struct *sender = t->from->proc->tsk; + t_from = binder_get_txn_from(t); + if (t_from) { + struct task_struct *sender = t_from->proc->tsk; - tr.sender_pid = task_tgid_nr_ns(sender, - task_active_pid_ns(current)); + trd->sender_pid = + task_tgid_nr_ns(sender, + task_active_pid_ns(current)); } else { - tr.sender_pid = 0; + trd->sender_pid = 0; } - tr.data_size = t->buffer->data_size; - tr.offsets_size = t->buffer->offsets_size; - tr.data.ptr.buffer = (binder_uintptr_t)( - (uintptr_t)t->buffer->data + - proc->user_buffer_offset); - tr.data.ptr.offsets = tr.data.ptr.buffer + + ret = binder_apply_fd_fixups(proc, t); + if (ret) { + struct binder_buffer *buffer = t->buffer; + bool oneway = !!(t->flags & TF_ONE_WAY); + int tid = t->debug_id; + + if (t_from) + binder_thread_dec_tmpref(t_from); + buffer->transaction = NULL; + binder_cleanup_transaction(t, "fd fixups failed", + BR_FAILED_REPLY); + binder_free_buf(proc, buffer); + binder_debug(BINDER_DEBUG_FAILED_TRANSACTION, + "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n", + proc->pid, thread->pid, + oneway ? "async " : + (cmd == BR_REPLY ? "reply " : ""), + tid, BR_FAILED_REPLY, ret, __LINE__); + if (cmd == BR_REPLY) { + cmd = BR_FAILED_REPLY; + if (put_user(cmd, (uint32_t __user *)ptr)) + return -EFAULT; + ptr += sizeof(uint32_t); + binder_stat_br(proc, thread, cmd); + break; + } + continue; + } + trd->data_size = t->buffer->data_size; + trd->offsets_size = t->buffer->offsets_size; + trd->data.ptr.buffer = (uintptr_t)t->buffer->user_data; + trd->data.ptr.offsets = trd->data.ptr.buffer + ALIGN(t->buffer->data_size, sizeof(void *)); - if (put_user(cmd, (uint32_t __user *)ptr)) + tr.secctx = t->security_ctx; + if (t->security_ctx) { + cmd = BR_TRANSACTION_SEC_CTX; + trsize = sizeof(tr); + } + if (put_user(cmd, (uint32_t __user *)ptr)) { + if (t_from) + binder_thread_dec_tmpref(t_from); + + binder_cleanup_transaction(t, "put_user failed", + BR_FAILED_REPLY); + return -EFAULT; + } ptr += sizeof(uint32_t); - if (copy_to_user(ptr, &tr, sizeof(tr))) + if (copy_to_user(ptr, &tr, trsize)) { + if (t_from) + binder_thread_dec_tmpref(t_from); + + binder_cleanup_transaction(t, "copy_to_user failed", + BR_FAILED_REPLY); + return -EFAULT; - ptr += sizeof(tr); + } + ptr += trsize; trace_binder_transaction_received(t); binder_stat_br(proc, thread, cmd); @@ -2999,22 +4514,25 @@ retry: "%d:%d %s %d %d:%d, cmd %d size %zd-%zd ptr %016llx-%016llx\n", proc->pid, thread->pid, (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" : - "BR_REPLY", - t->debug_id, t->from ? t->from->proc->pid : 0, - t->from ? t->from->pid : 0, cmd, + (cmd == BR_TRANSACTION_SEC_CTX) ? + "BR_TRANSACTION_SEC_CTX" : "BR_REPLY", + t->debug_id, t_from ? t_from->proc->pid : 0, + t_from ? t_from->pid : 0, cmd, t->buffer->data_size, t->buffer->offsets_size, - (u64)tr.data.ptr.buffer, (u64)tr.data.ptr.offsets); + (u64)trd->data.ptr.buffer, + (u64)trd->data.ptr.offsets); - list_del(&t->work.entry); + if (t_from) + binder_thread_dec_tmpref(t_from); t->buffer->allow_user_free = 1; - if (cmd == BR_TRANSACTION && !(t->flags & TF_ONE_WAY)) { + if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) { + binder_inner_proc_lock(thread->proc); t->to_parent = thread->transaction_stack; t->to_thread = thread; thread->transaction_stack = t; + binder_inner_proc_unlock(thread->proc); } else { - t->buffer->transaction = NULL; - kfree(t); - binder_stats_deleted(BINDER_STAT_TRANSACTION); + binder_free_transaction(t); } break; } @@ -3022,45 +4540,56 @@ retry: done: *consumed = ptr - buffer; - if (proc->requested_threads + proc->ready_threads == 0 && + binder_inner_proc_lock(proc); + if (proc->requested_threads == 0 && + list_empty(&thread->proc->waiting_threads) && proc->requested_threads_started < proc->max_threads && (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */ /*spawn a new thread if we leave this out */) { proc->requested_threads++; + binder_inner_proc_unlock(proc); binder_debug(BINDER_DEBUG_THREADS, "%d:%d BR_SPAWN_LOOPER\n", proc->pid, thread->pid); if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer)) return -EFAULT; binder_stat_br(proc, thread, BR_SPAWN_LOOPER); - } + } else + binder_inner_proc_unlock(proc); return 0; } -static void binder_release_work(struct list_head *list) +static void binder_release_work(struct binder_proc *proc, + struct list_head *list) { struct binder_work *w; + enum binder_work_type wtype; - while (!list_empty(list)) { - w = list_first_entry(list, struct binder_work, entry); - list_del_init(&w->entry); - switch (w->type) { + while (1) { + binder_inner_proc_lock(proc); + w = binder_dequeue_work_head_ilocked(list); + wtype = w ? w->type : 0; + binder_inner_proc_unlock(proc); + if (!w) + return; + + switch (wtype) { case BINDER_WORK_TRANSACTION: { struct binder_transaction *t; t = container_of(w, struct binder_transaction, work); - if (t->buffer->target_node && - !(t->flags & TF_ONE_WAY)) { - binder_send_failed_reply(t, BR_DEAD_REPLY); - } else { - binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, - "undelivered transaction %d\n", - t->debug_id); - t->buffer->transaction = NULL; - kfree(t); - binder_stats_deleted(BINDER_STAT_TRANSACTION); - } + + binder_cleanup_transaction(t, "process died.", + BR_DEAD_REPLY); + } break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, + "undelivered TRANSACTION_ERROR: %u\n", + e->cmd); } break; case BINDER_WORK_TRANSACTION_COMPLETE: { binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, @@ -3079,16 +4608,19 @@ static void binder_release_work(struct list_head *list) kfree(death); binder_stats_deleted(BINDER_STAT_DEATH); } break; + case BINDER_WORK_NODE: + break; default: pr_err("unexpected work type, %d, not freed\n", - w->type); + wtype); break; } } } -static struct binder_thread *binder_get_thread(struct binder_proc *proc) +static struct binder_thread *binder_get_thread_ilocked( + struct binder_proc *proc, struct binder_thread *new_thread) { struct binder_thread *thread = NULL; struct rb_node *parent = NULL; @@ -3103,38 +4635,108 @@ static struct binder_thread *binder_get_thread(struct binder_proc *proc) else if (current->pid > thread->pid) p = &(*p)->rb_right; else - break; + return thread; } - if (*p == NULL) { - thread = kzalloc(sizeof(*thread), GFP_KERNEL); - if (thread == NULL) + if (!new_thread) + return NULL; + thread = new_thread; + binder_stats_created(BINDER_STAT_THREAD); + thread->proc = proc; + thread->pid = current->pid; + atomic_set(&thread->tmp_ref, 0); + init_waitqueue_head(&thread->wait); + INIT_LIST_HEAD(&thread->todo); + rb_link_node(&thread->rb_node, parent, p); + rb_insert_color(&thread->rb_node, &proc->threads); + thread->looper_need_return = true; + thread->return_error.work.type = BINDER_WORK_RETURN_ERROR; + thread->return_error.cmd = BR_OK; + thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR; + thread->reply_error.cmd = BR_OK; + INIT_LIST_HEAD(&new_thread->waiting_thread_node); + return thread; +} + +static struct binder_thread *binder_get_thread(struct binder_proc *proc) +{ + struct binder_thread *thread; + struct binder_thread *new_thread; + + binder_inner_proc_lock(proc); + thread = binder_get_thread_ilocked(proc, NULL); + binder_inner_proc_unlock(proc); + if (!thread) { + new_thread = kzalloc(sizeof(*thread), GFP_KERNEL); + if (new_thread == NULL) return NULL; - binder_stats_created(BINDER_STAT_THREAD); - thread->proc = proc; - thread->pid = current->pid; - init_waitqueue_head(&thread->wait); - INIT_LIST_HEAD(&thread->todo); - rb_link_node(&thread->rb_node, parent, p); - rb_insert_color(&thread->rb_node, &proc->threads); - thread->looper |= BINDER_LOOPER_STATE_NEED_RETURN; - thread->return_error = BR_OK; - thread->return_error2 = BR_OK; + binder_inner_proc_lock(proc); + thread = binder_get_thread_ilocked(proc, new_thread); + binder_inner_proc_unlock(proc); + if (thread != new_thread) + kfree(new_thread); } return thread; } -static int binder_free_thread(struct binder_proc *proc, - struct binder_thread *thread) +static void binder_free_proc(struct binder_proc *proc) +{ + struct binder_device *device; + + BUG_ON(!list_empty(&proc->todo)); + BUG_ON(!list_empty(&proc->delivered_death)); + device = container_of(proc->context, struct binder_device, context); + if (refcount_dec_and_test(&device->ref)) { + kfree(proc->context->name); + kfree(device); + } + binder_alloc_deferred_release(&proc->alloc); + put_task_struct(proc->tsk); + binder_stats_deleted(BINDER_STAT_PROC); + kfree(proc); +} + +static void binder_free_thread(struct binder_thread *thread) +{ + BUG_ON(!list_empty(&thread->todo)); + binder_stats_deleted(BINDER_STAT_THREAD); + binder_proc_dec_tmpref(thread->proc); + kfree(thread); +} + +static int binder_thread_release(struct binder_proc *proc, + struct binder_thread *thread) { struct binder_transaction *t; struct binder_transaction *send_reply = NULL; int active_transactions = 0; + struct binder_transaction *last_t = NULL; + binder_inner_proc_lock(thread->proc); + /* + * take a ref on the proc so it survives + * after we remove this thread from proc->threads. + * The corresponding dec is when we actually + * free the thread in binder_free_thread() + */ + proc->tmp_ref++; + /* + * take a ref on this thread to ensure it + * survives while we are releasing it + */ + atomic_inc(&thread->tmp_ref); rb_erase(&thread->rb_node, &proc->threads); t = thread->transaction_stack; - if (t && t->to_thread == thread) - send_reply = t; + if (t) { + spin_lock(&t->lock); + if (t->to_thread == thread) + send_reply = t; + } else { + __acquire(&t->lock); + } + thread->is_dead = true; + while (t) { + last_t = t; active_transactions++; binder_debug(BINDER_DEBUG_DEAD_TRANSACTION, "release %d:%d transaction %d %s, still active\n", @@ -3155,44 +4757,66 @@ static int binder_free_thread(struct binder_proc *proc, t = t->from_parent; } else BUG(); + spin_unlock(&last_t->lock); + if (t) + spin_lock(&t->lock); + else + __acquire(&t->lock); } + /* annotation for sparse, lock not acquired in last iteration above */ + __release(&t->lock); + + /* + * If this thread used poll, make sure we remove the waitqueue + * from any epoll data structures holding it with POLLFREE. + * waitqueue_active() is safe to use here because we're holding + * the inner lock. + */ + if ((thread->looper & BINDER_LOOPER_STATE_POLL) && + waitqueue_active(&thread->wait)) { + wake_up_poll(&thread->wait, EPOLLHUP | POLLFREE); + } + + binder_inner_proc_unlock(thread->proc); + + /* + * This is needed to avoid races between wake_up_poll() above and + * and ep_remove_waitqueue() called for other reasons (eg the epoll file + * descriptor being closed); ep_remove_waitqueue() holds an RCU read + * lock, so we can be sure it's done after calling synchronize_rcu(). + */ + if (thread->looper & BINDER_LOOPER_STATE_POLL) + synchronize_rcu(); + if (send_reply) binder_send_failed_reply(send_reply, BR_DEAD_REPLY); - binder_release_work(&thread->todo); - kfree(thread); - binder_stats_deleted(BINDER_STAT_THREAD); + binder_release_work(proc, &thread->todo); + binder_thread_dec_tmpref(thread); return active_transactions; } -static unsigned int binder_poll(struct file *filp, +static __poll_t binder_poll(struct file *filp, struct poll_table_struct *wait) { struct binder_proc *proc = filp->private_data; struct binder_thread *thread = NULL; - int wait_for_proc_work; - - binder_lock(__func__); + bool wait_for_proc_work; thread = binder_get_thread(proc); + if (!thread) + return POLLERR; - wait_for_proc_work = thread->transaction_stack == NULL && - list_empty(&thread->todo) && thread->return_error == BR_OK; + binder_inner_proc_lock(thread->proc); + thread->looper |= BINDER_LOOPER_STATE_POLL; + wait_for_proc_work = binder_available_for_proc_work_ilocked(thread); - binder_unlock(__func__); + binder_inner_proc_unlock(thread->proc); + + poll_wait(filp, &thread->wait, wait); + + if (binder_has_work(thread, wait_for_proc_work)) + return EPOLLIN; - if (wait_for_proc_work) { - if (binder_has_proc_work(proc, thread)) - return POLLIN; - poll_wait(filp, &proc->wait, wait); - if (binder_has_proc_work(proc, thread)) - return POLLIN; - } else { - if (binder_has_thread_work(thread)) - return POLLIN; - poll_wait(filp, &thread->wait, wait); - if (binder_has_thread_work(thread)) - return POLLIN; - } return 0; } @@ -3239,8 +4863,10 @@ static int binder_ioctl_write_read(struct file *filp, &bwr.read_consumed, filp->f_flags & O_NONBLOCK); trace_binder_read_done(ret); - if (!list_empty(&proc->todo)) - wake_up_interruptible(&proc->wait); + binder_inner_proc_lock(proc); + if (!binder_worklist_empty_ilocked(&proc->todo)) + binder_wakeup_proc_ilocked(proc); + binder_inner_proc_unlock(proc); if (ret < 0) { if (copy_to_user(ubuf, &bwr, sizeof(bwr))) ret = -EFAULT; @@ -3260,24 +4886,24 @@ out: return ret; } -static int binder_ioctl_set_ctx_mgr(struct file *filp) +static int binder_ioctl_set_ctx_mgr(struct file *filp, + struct flat_binder_object *fbo) { int ret = 0; struct binder_proc *proc = filp->private_data; struct binder_context *context = proc->context; - + struct binder_node *new_node; kuid_t curr_euid = current_euid(); + mutex_lock(&context->context_mgr_node_lock); if (context->binder_context_mgr_node) { pr_err("BINDER_SET_CONTEXT_MGR already set\n"); ret = -EBUSY; goto out; } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 0, 0) ret = security_binder_set_context_mgr(proc->tsk); if (ret < 0) goto out; -#endif if (uid_valid(context->binder_context_mgr_uid)) { if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) { pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n", @@ -3290,19 +4916,85 @@ static int binder_ioctl_set_ctx_mgr(struct file *filp) } else { context->binder_context_mgr_uid = curr_euid; } - context->binder_context_mgr_node = binder_new_node(proc, 0, 0); - if (!context->binder_context_mgr_node) { + new_node = binder_new_node(proc, fbo); + if (!new_node) { ret = -ENOMEM; goto out; } - context->binder_context_mgr_node->local_weak_refs++; - context->binder_context_mgr_node->local_strong_refs++; - context->binder_context_mgr_node->has_strong_ref = 1; - context->binder_context_mgr_node->has_weak_ref = 1; + binder_node_lock(new_node); + new_node->local_weak_refs++; + new_node->local_strong_refs++; + new_node->has_strong_ref = 1; + new_node->has_weak_ref = 1; + context->binder_context_mgr_node = new_node; + binder_node_unlock(new_node); + binder_put_node(new_node); out: + mutex_unlock(&context->context_mgr_node_lock); return ret; } +static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc, + struct binder_node_info_for_ref *info) +{ + struct binder_node *node; + struct binder_context *context = proc->context; + __u32 handle = info->handle; + + if (info->strong_count || info->weak_count || info->reserved1 || + info->reserved2 || info->reserved3) { + binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.", + proc->pid); + return -EINVAL; + } + + /* This ioctl may only be used by the context manager */ + mutex_lock(&context->context_mgr_node_lock); + if (!context->binder_context_mgr_node || + context->binder_context_mgr_node->proc != proc) { + mutex_unlock(&context->context_mgr_node_lock); + return -EPERM; + } + mutex_unlock(&context->context_mgr_node_lock); + + node = binder_get_node_from_ref(proc, handle, true, NULL); + if (!node) + return -EINVAL; + + info->strong_count = node->local_strong_refs + + node->internal_strong_refs; + info->weak_count = node->local_weak_refs; + + binder_put_node(node); + + return 0; +} + +static int binder_ioctl_get_node_debug_info(struct binder_proc *proc, + struct binder_node_debug_info *info) +{ + struct rb_node *n; + binder_uintptr_t ptr = info->ptr; + + memset(info, 0, sizeof(*info)); + + binder_inner_proc_lock(proc); + for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) { + struct binder_node *node = rb_entry(n, struct binder_node, + rb_node); + if (node->ptr > ptr) { + info->ptr = node->ptr; + info->cookie = node->cookie; + info->has_strong_ref = node->has_strong_ref; + info->has_weak_ref = node->has_weak_ref; + break; + } + } + binder_inner_proc_unlock(proc); + + return 0; +} + static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { int ret; @@ -3314,13 +5006,14 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) /*pr_info("binder_ioctl: %d:%d %x %lx\n", proc->pid, current->pid, cmd, arg);*/ + binder_selftest_alloc(&proc->alloc); + trace_binder_ioctl(cmd, arg); ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); if (ret) goto err_unlocked; - binder_lock(__func__); thread = binder_get_thread(proc); if (thread == NULL) { ret = -ENOMEM; @@ -3333,21 +5026,40 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (ret) goto err; break; - case BINDER_SET_MAX_THREADS: - if (copy_from_user(&proc->max_threads, ubuf, sizeof(proc->max_threads))) { + case BINDER_SET_MAX_THREADS: { + int max_threads; + + if (copy_from_user(&max_threads, ubuf, + sizeof(max_threads))) { ret = -EINVAL; goto err; } + binder_inner_proc_lock(proc); + proc->max_threads = max_threads; + binder_inner_proc_unlock(proc); break; + } + case BINDER_SET_CONTEXT_MGR_EXT: { + struct flat_binder_object fbo; + + if (copy_from_user(&fbo, ubuf, sizeof(fbo))) { + ret = -EINVAL; + goto err; + } + ret = binder_ioctl_set_ctx_mgr(filp, &fbo); + if (ret) + goto err; + break; + } case BINDER_SET_CONTEXT_MGR: - ret = binder_ioctl_set_ctx_mgr(filp); + ret = binder_ioctl_set_ctx_mgr(filp, NULL); if (ret) goto err; break; case BINDER_THREAD_EXIT: binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n", proc->pid, thread->pid); - binder_free_thread(proc, thread); + binder_thread_release(proc, thread); thread = NULL; break; case BINDER_VERSION: { @@ -3364,6 +5076,43 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) } break; } + case BINDER_GET_NODE_INFO_FOR_REF: { + struct binder_node_info_for_ref info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_node_info_for_ref(proc, &info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + break; + } + case BINDER_GET_NODE_DEBUG_INFO: { + struct binder_node_debug_info info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_node_debug_info(proc, &info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + break; + } default: ret = -EINVAL; goto err; @@ -3371,8 +5120,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) ret = 0; err: if (thread) - thread->looper &= ~BINDER_LOOPER_STATE_NEED_RETURN; - binder_unlock(__func__); + thread->looper_need_return = false; wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2); if (ret && ret != -ERESTARTSYS) pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret); @@ -3401,18 +5149,10 @@ static void binder_vma_close(struct vm_area_struct *vma) proc->pid, vma->vm_start, vma->vm_end, (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags, (unsigned long)pgprot_val(vma->vm_page_prot)); - proc->vma = NULL; - proc->vma_vm_mm = NULL; - binder_defer_work(proc, BINDER_DEFERRED_PUT_FILES); + binder_alloc_vma_close(&proc->alloc); } -#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 1, 0) static vm_fault_t binder_vm_fault(struct vm_fault *vmf) -#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) -static int binder_vm_fault(struct vm_fault *vmf) -#else -static int binder_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) -#endif { return VM_FAULT_SIGBUS; } @@ -3425,160 +5165,118 @@ static const struct vm_operations_struct binder_vm_ops = { static int binder_mmap(struct file *filp, struct vm_area_struct *vma) { - int ret; - struct vm_struct *area; struct binder_proc *proc = filp->private_data; - const char *failure_string; - struct binder_buffer *buffer; - if (proc->tsk != current) + if (proc->tsk != current->group_leader) return -EINVAL; - if ((vma->vm_end - vma->vm_start) > SZ_4M) - vma->vm_end = vma->vm_start + SZ_4M; - binder_debug(BINDER_DEBUG_OPEN_CLOSE, - "binder_mmap: %d %lx-%lx (%ld K) vma %lx pagep %lx\n", - proc->pid, vma->vm_start, vma->vm_end, + "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n", + __func__, proc->pid, vma->vm_start, vma->vm_end, (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags, (unsigned long)pgprot_val(vma->vm_page_prot)); if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) { - ret = -EPERM; - failure_string = "bad vm_flags"; - goto err_bad_arg; + pr_err("%s: %d %lx-%lx %s failed %d\n", __func__, + proc->pid, vma->vm_start, vma->vm_end, "bad vm_flags", -EPERM); + return -EPERM; } - vma->vm_flags = (vma->vm_flags | VM_DONTCOPY) & ~VM_MAYWRITE; - - mutex_lock(&binder_mmap_lock); - if (proc->buffer) { - ret = -EBUSY; - failure_string = "already mapped"; - goto err_already_mapped; - } - - area = get_vm_area(vma->vm_end - vma->vm_start, VM_IOREMAP); - if (area == NULL) { - ret = -ENOMEM; - failure_string = "get_vm_area"; - goto err_get_vm_area_failed; - } - proc->buffer = area->addr; - proc->user_buffer_offset = vma->vm_start - (uintptr_t)proc->buffer; - mutex_unlock(&binder_mmap_lock); - -#ifdef CONFIG_CPU_CACHE_VIPT - if (cache_is_vipt_aliasing()) { - while (CACHE_COLOUR((vma->vm_start ^ (uint32_t)proc->buffer))) { - pr_info("binder_mmap: %d %lx-%lx maps %p bad alignment\n", proc->pid, vma->vm_start, vma->vm_end, proc->buffer); - vma->vm_start += PAGE_SIZE; - } - } -#endif - proc->pages = kzalloc(sizeof(proc->pages[0]) * ((vma->vm_end - vma->vm_start) / PAGE_SIZE), GFP_KERNEL); - if (proc->pages == NULL) { - ret = -ENOMEM; - failure_string = "alloc page array"; - goto err_alloc_pages_failed; - } - proc->buffer_size = vma->vm_end - vma->vm_start; + vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP; + vma->vm_flags &= ~VM_MAYWRITE; vma->vm_ops = &binder_vm_ops; vma->vm_private_data = proc; - if (binder_update_page_range(proc, 1, proc->buffer, proc->buffer + PAGE_SIZE, vma)) { - ret = -ENOMEM; - failure_string = "alloc small buf"; - goto err_alloc_small_buf_failed; - } - buffer = proc->buffer; - INIT_LIST_HEAD(&proc->buffers); - list_add(&buffer->entry, &proc->buffers); - buffer->free = 1; - binder_insert_free_buffer(proc, buffer); - proc->free_async_space = proc->buffer_size / 2; - barrier(); - proc->files = get_files_struct(current); - proc->vma = vma; - proc->vma_vm_mm = vma->vm_mm; - - /*pr_info("binder_mmap: %d %lx-%lx maps %p\n", - proc->pid, vma->vm_start, vma->vm_end, proc->buffer);*/ - return 0; - -err_alloc_small_buf_failed: - kfree(proc->pages); - proc->pages = NULL; -err_alloc_pages_failed: - mutex_lock(&binder_mmap_lock); - vfree(proc->buffer); - proc->buffer = NULL; -err_get_vm_area_failed: -err_already_mapped: - mutex_unlock(&binder_mmap_lock); -err_bad_arg: - pr_err("binder_mmap: %d %lx-%lx %s failed %d\n", - proc->pid, vma->vm_start, vma->vm_end, failure_string, ret); - return ret; + return binder_alloc_mmap_handler(&proc->alloc, vma); } static int binder_open(struct inode *nodp, struct file *filp) { - int minor = iminor(nodp); - struct hlist_node *tmp; - struct binder_proc *proc; + struct binder_proc *proc, *itr; struct binder_device *binder_dev; + struct binderfs_info *info; + struct dentry *binder_binderfs_dir_entry_proc = NULL; + bool existing_pid = false; - binder_debug(BINDER_DEBUG_OPEN_CLOSE, "binder_open: %d:%d\n", + binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__, current->group_leader->pid, current->pid); proc = kzalloc(sizeof(*proc), GFP_KERNEL); if (proc == NULL) return -ENOMEM; + spin_lock_init(&proc->inner_lock); + spin_lock_init(&proc->outer_lock); get_task_struct(current->group_leader); proc->tsk = current->group_leader; INIT_LIST_HEAD(&proc->todo); - init_waitqueue_head(&proc->wait); proc->default_priority = task_nice(current); - - mutex_lock(&binder_devices_mtx); - hlist_for_each_entry_safe(binder_dev, tmp, &binder_devices, hlist) { - if (MINOR(binder_dev->cdev.dev) == minor) - break; - binder_dev = NULL; + /* binderfs stashes devices in i_private */ + if (is_binderfs_device(nodp)) { + binder_dev = nodp->i_private; + info = nodp->i_sb->s_fs_info; + binder_binderfs_dir_entry_proc = info->proc_log_dir; + } else { + binder_dev = container_of(filp->private_data, + struct binder_device, miscdev); } - mutex_unlock(&binder_devices_mtx); - if (!binder_dev) - BUG(); - - filp->private_data = &binder_dev->class_dev; + refcount_inc(&binder_dev->ref); proc->context = &binder_dev->context; - - binder_lock(__func__); + binder_alloc_init(&proc->alloc); binder_stats_created(BINDER_STAT_PROC); - hlist_add_head(&proc->proc_node, &binder_procs); proc->pid = current->group_leader->pid; INIT_LIST_HEAD(&proc->delivered_death); + INIT_LIST_HEAD(&proc->waiting_threads); filp->private_data = proc; - binder_unlock(__func__); + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(itr, &binder_procs, proc_node) { + if (itr->pid == proc->pid) { + existing_pid = true; + break; + } + } + hlist_add_head(&proc->proc_node, &binder_procs); + mutex_unlock(&binder_procs_lock); - if (binder_debugfs_dir_entry_proc) { + if (binder_debugfs_dir_entry_proc && !existing_pid) { char strbuf[11]; snprintf(strbuf, sizeof(strbuf), "%u", proc->pid); /* - * proc debug entries are shared between contexts, so - * this will fail if the process tries to open the driver - * again with a different context. The priting code will - * anyway print all contexts that a given PID has, so this - * is not a problem. + * proc debug entries are shared between contexts. + * Only create for the first PID to avoid debugfs log spamming + * The printing code will anyway print all contexts for a given + * PID so this is not a problem. */ - proc->debugfs_entry = debugfs_create_file(strbuf, S_IRUGO, + proc->debugfs_entry = debugfs_create_file(strbuf, 0444, binder_debugfs_dir_entry_proc, (void *)(unsigned long)proc->pid, - &binder_proc_fops); + &proc_fops); + } + + if (binder_binderfs_dir_entry_proc && !existing_pid) { + char strbuf[11]; + struct dentry *binderfs_entry; + + snprintf(strbuf, sizeof(strbuf), "%u", proc->pid); + /* + * Similar to debugfs, the process specific log file is shared + * between contexts. Only create for the first PID. + * This is ok since same as debugfs, the log file will contain + * information on all contexts of a given PID. + */ + binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc, + strbuf, &proc_fops, (void *)(unsigned long)proc->pid); + if (!IS_ERR(binderfs_entry)) { + proc->binderfs_entry = binderfs_entry; + } else { + int error; + + error = PTR_ERR(binderfs_entry); + pr_warn("Unable to create file %s in binderfs (error %d)\n", + strbuf, error); + } } return 0; @@ -3598,16 +5296,17 @@ static void binder_deferred_flush(struct binder_proc *proc) struct rb_node *n; int wake_count = 0; + binder_inner_proc_lock(proc); for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) { struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node); - thread->looper |= BINDER_LOOPER_STATE_NEED_RETURN; + thread->looper_need_return = true; if (thread->looper & BINDER_LOOPER_STATE_WAITING) { wake_up_interruptible(&thread->wait); wake_count++; } } - wake_up_interruptible_all(&proc->wait); + binder_inner_proc_unlock(proc); binder_debug(BINDER_DEBUG_OPEN_CLOSE, "binder_flush: %d woke %d threads\n", proc->pid, @@ -3619,6 +5318,12 @@ static int binder_release(struct inode *nodp, struct file *filp) struct binder_proc *proc = filp->private_data; debugfs_remove(proc->debugfs_entry); + + if (proc->binderfs_entry) { + binderfs_remove_file(proc->binderfs_entry); + proc->binderfs_entry = NULL; + } + binder_defer_work(proc, BINDER_DEFERRED_RELEASE); return 0; @@ -3628,13 +5333,21 @@ static int binder_node_release(struct binder_node *node, int refs) { struct binder_ref *ref; int death = 0; + struct binder_proc *proc = node->proc; - list_del_init(&node->work.entry); - binder_release_work(&node->async_todo); + binder_release_work(proc, &node->async_todo); - if (hlist_empty(&node->refs)) { - kfree(node); - binder_stats_deleted(BINDER_STAT_NODE); + binder_node_lock(node); + binder_inner_proc_lock(proc); + binder_dequeue_work_ilocked(&node->work); + /* + * The caller must have taken a temporary ref on the node, + */ + BUG_ON(!node->tmp_refs); + if (hlist_empty(&node->refs) && node->tmp_refs == 1) { + binder_inner_proc_unlock(proc); + binder_node_unlock(node); + binder_free_node(node); return refs; } @@ -3642,45 +5355,56 @@ static int binder_node_release(struct binder_node *node, int refs) node->proc = NULL; node->local_strong_refs = 0; node->local_weak_refs = 0; + binder_inner_proc_unlock(proc); + + spin_lock(&binder_dead_nodes_lock); hlist_add_head(&node->dead_node, &binder_dead_nodes); + spin_unlock(&binder_dead_nodes_lock); hlist_for_each_entry(ref, &node->refs, node_entry) { refs++; - - if (!ref->death) + /* + * Need the node lock to synchronize + * with new notification requests and the + * inner lock to synchronize with queued + * death notifications. + */ + binder_inner_proc_lock(ref->proc); + if (!ref->death) { + binder_inner_proc_unlock(ref->proc); continue; + } death++; - if (list_empty(&ref->death->work.entry)) { - ref->death->work.type = BINDER_WORK_DEAD_BINDER; - list_add_tail(&ref->death->work.entry, - &ref->proc->todo); - wake_up_interruptible(&ref->proc->wait); - } else - BUG(); + BUG_ON(!list_empty(&ref->death->work.entry)); + ref->death->work.type = BINDER_WORK_DEAD_BINDER; + binder_enqueue_work_ilocked(&ref->death->work, + &ref->proc->todo); + binder_wakeup_proc_ilocked(ref->proc); + binder_inner_proc_unlock(ref->proc); } binder_debug(BINDER_DEBUG_DEAD_BINDER, "node %d now dead, refs %d, death %d\n", node->debug_id, refs, death); + binder_node_unlock(node); + binder_put_node(node); return refs; } static void binder_deferred_release(struct binder_proc *proc) { - struct binder_transaction *t; struct binder_context *context = proc->context; struct rb_node *n; - int threads, nodes, incoming_refs, outgoing_refs, buffers, - active_transactions, page_count; - - BUG_ON(proc->vma); - BUG_ON(proc->files); + int threads, nodes, incoming_refs, outgoing_refs, active_transactions; + mutex_lock(&binder_procs_lock); hlist_del(&proc->proc_node); + mutex_unlock(&binder_procs_lock); + mutex_lock(&context->context_mgr_node_lock); if (context->binder_context_mgr_node && context->binder_context_mgr_node->proc == proc) { binder_debug(BINDER_DEBUG_DEAD_BINDER, @@ -3688,15 +5412,25 @@ static void binder_deferred_release(struct binder_proc *proc) __func__, proc->pid); context->binder_context_mgr_node = NULL; } + mutex_unlock(&context->context_mgr_node_lock); + binder_inner_proc_lock(proc); + /* + * Make sure proc stays alive after we + * remove all the threads + */ + proc->tmp_ref++; + proc->is_dead = true; threads = 0; active_transactions = 0; while ((n = rb_first(&proc->threads))) { struct binder_thread *thread; thread = rb_entry(n, struct binder_thread, rb_node); + binder_inner_proc_unlock(proc); threads++; - active_transactions += binder_free_thread(proc, thread); + active_transactions += binder_thread_release(proc, thread); + binder_inner_proc_lock(proc); } nodes = 0; @@ -3706,84 +5440,51 @@ static void binder_deferred_release(struct binder_proc *proc) node = rb_entry(n, struct binder_node, rb_node); nodes++; + /* + * take a temporary ref on the node before + * calling binder_node_release() which will either + * kfree() the node or call binder_put_node() + */ + binder_inc_node_tmpref_ilocked(node); rb_erase(&node->rb_node, &proc->nodes); + binder_inner_proc_unlock(proc); incoming_refs = binder_node_release(node, incoming_refs); + binder_inner_proc_lock(proc); } + binder_inner_proc_unlock(proc); outgoing_refs = 0; + binder_proc_lock(proc); while ((n = rb_first(&proc->refs_by_desc))) { struct binder_ref *ref; ref = rb_entry(n, struct binder_ref, rb_node_desc); outgoing_refs++; - binder_delete_ref(ref); + binder_cleanup_ref_olocked(ref); + binder_proc_unlock(proc); + binder_free_ref(ref); + binder_proc_lock(proc); } + binder_proc_unlock(proc); - binder_release_work(&proc->todo); - binder_release_work(&proc->delivered_death); - - buffers = 0; - while ((n = rb_first(&proc->allocated_buffers))) { - struct binder_buffer *buffer; - - buffer = rb_entry(n, struct binder_buffer, rb_node); - - t = buffer->transaction; - if (t) { - t->buffer = NULL; - buffer->transaction = NULL; - pr_err("release proc %d, transaction %d, not freed\n", - proc->pid, t->debug_id); - /*BUG();*/ - } - - binder_free_buf(proc, buffer); - buffers++; - } - - binder_stats_deleted(BINDER_STAT_PROC); - - page_count = 0; - if (proc->pages) { - int i; - - for (i = 0; i < proc->buffer_size / PAGE_SIZE; i++) { - void *page_addr; - - if (!proc->pages[i]) - continue; - - page_addr = proc->buffer + i * PAGE_SIZE; - binder_debug(BINDER_DEBUG_BUFFER_ALLOC, - "%s: %d: page %d at %p not freed\n", - __func__, proc->pid, i, page_addr); - unmap_kernel_range((unsigned long)page_addr, PAGE_SIZE); - __free_page(proc->pages[i]); - page_count++; - } - kfree(proc->pages); - vfree(proc->buffer); - } - - put_task_struct(proc->tsk); + binder_release_work(proc, &proc->todo); + binder_release_work(proc, &proc->delivered_death); binder_debug(BINDER_DEBUG_OPEN_CLOSE, - "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d, buffers %d, pages %d\n", + "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n", __func__, proc->pid, threads, nodes, incoming_refs, - outgoing_refs, active_transactions, buffers, page_count); + outgoing_refs, active_transactions); - kfree(proc); + binder_proc_dec_tmpref(proc); } static void binder_deferred_func(struct work_struct *work) { struct binder_proc *proc; - struct files_struct *files; int defer; do { - binder_lock(__func__); mutex_lock(&binder_deferred_lock); if (!hlist_empty(&binder_deferred_list)) { proc = hlist_entry(binder_deferred_list.first, @@ -3797,22 +5498,11 @@ static void binder_deferred_func(struct work_struct *work) } mutex_unlock(&binder_deferred_lock); - files = NULL; - if (defer & BINDER_DEFERRED_PUT_FILES) { - files = proc->files; - if (files) - proc->files = NULL; - } - if (defer & BINDER_DEFERRED_FLUSH) binder_deferred_flush(proc); if (defer & BINDER_DEFERRED_RELEASE) binder_deferred_release(proc); /* frees proc */ - - binder_unlock(__func__); - if (files) - put_files_struct(files); } while (proc); } static DECLARE_WORK(binder_deferred_work, binder_deferred_func); @@ -3830,41 +5520,51 @@ binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer) mutex_unlock(&binder_deferred_lock); } -static void print_binder_transaction(struct seq_file *m, const char *prefix, - struct binder_transaction *t) +static void print_binder_transaction_ilocked(struct seq_file *m, + struct binder_proc *proc, + const char *prefix, + struct binder_transaction *t) { + struct binder_proc *to_proc; + struct binder_buffer *buffer = t->buffer; + + spin_lock(&t->lock); + to_proc = t->to_proc; seq_printf(m, - "%s %d: %p from %d:%d to %d:%d code %x flags %x pri %ld r%d", + "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld r%d", prefix, t->debug_id, t, t->from ? t->from->proc->pid : 0, t->from ? t->from->pid : 0, - t->to_proc ? t->to_proc->pid : 0, + to_proc ? to_proc->pid : 0, t->to_thread ? t->to_thread->pid : 0, t->code, t->flags, t->priority, t->need_reply); - if (t->buffer == NULL) { + spin_unlock(&t->lock); + + if (proc != to_proc) { + /* + * Can only safely deref buffer if we are holding the + * correct proc inner lock for this node + */ + seq_puts(m, "\n"); + return; + } + + if (buffer == NULL) { seq_puts(m, " buffer free\n"); return; } - if (t->buffer->target_node) - seq_printf(m, " node %d", - t->buffer->target_node->debug_id); - seq_printf(m, " size %zd:%zd data %p\n", - t->buffer->data_size, t->buffer->offsets_size, - t->buffer->data); -} - -static void print_binder_buffer(struct seq_file *m, const char *prefix, - struct binder_buffer *buffer) -{ - seq_printf(m, "%s %d: %p size %zd:%zd %s\n", - prefix, buffer->debug_id, buffer->data, + if (buffer->target_node) + seq_printf(m, " node %d", buffer->target_node->debug_id); + seq_printf(m, " size %zd:%zd data %pK\n", buffer->data_size, buffer->offsets_size, - buffer->transaction ? "active" : "delivered"); + buffer->user_data); } -static void print_binder_work(struct seq_file *m, const char *prefix, - const char *transaction_prefix, - struct binder_work *w) +static void print_binder_work_ilocked(struct seq_file *m, + struct binder_proc *proc, + const char *prefix, + const char *transaction_prefix, + struct binder_work *w) { struct binder_node *node; struct binder_transaction *t; @@ -3872,8 +5572,16 @@ static void print_binder_work(struct seq_file *m, const char *prefix, switch (w->type) { case BINDER_WORK_TRANSACTION: t = container_of(w, struct binder_transaction, work); - print_binder_transaction(m, transaction_prefix, t); + print_binder_transaction_ilocked( + m, proc, transaction_prefix, t); break; + case BINDER_WORK_RETURN_ERROR: { + struct binder_error *e = container_of( + w, struct binder_error, work); + + seq_printf(m, "%stransaction error: %u\n", + prefix, e->cmd); + } break; case BINDER_WORK_TRANSACTION_COMPLETE: seq_printf(m, "%stransaction complete\n", prefix); break; @@ -3898,40 +5606,46 @@ static void print_binder_work(struct seq_file *m, const char *prefix, } } -static void print_binder_thread(struct seq_file *m, - struct binder_thread *thread, - int print_always) +static void print_binder_thread_ilocked(struct seq_file *m, + struct binder_thread *thread, + int print_always) { struct binder_transaction *t; struct binder_work *w; size_t start_pos = m->count; size_t header_pos; - seq_printf(m, " thread %d: l %02x\n", thread->pid, thread->looper); + seq_printf(m, " thread %d: l %02x need_return %d tr %d\n", + thread->pid, thread->looper, + thread->looper_need_return, + atomic_read(&thread->tmp_ref)); header_pos = m->count; t = thread->transaction_stack; while (t) { if (t->from == thread) { - print_binder_transaction(m, - " outgoing transaction", t); + print_binder_transaction_ilocked(m, thread->proc, + " outgoing transaction", t); t = t->from_parent; } else if (t->to_thread == thread) { - print_binder_transaction(m, + print_binder_transaction_ilocked(m, thread->proc, " incoming transaction", t); t = t->to_parent; } else { - print_binder_transaction(m, " bad transaction", t); + print_binder_transaction_ilocked(m, thread->proc, + " bad transaction", t); t = NULL; } } list_for_each_entry(w, &thread->todo, entry) { - print_binder_work(m, " ", " pending transaction", w); + print_binder_work_ilocked(m, thread->proc, " ", + " pending transaction", w); } if (!print_always && m->count == header_pos) m->count = start_pos; } -static void print_binder_node(struct seq_file *m, struct binder_node *node) +static void print_binder_node_nilocked(struct seq_file *m, + struct binder_node *node) { struct binder_ref *ref; struct binder_work *w; @@ -3941,27 +5655,34 @@ static void print_binder_node(struct seq_file *m, struct binder_node *node) hlist_for_each_entry(ref, &node->refs, node_entry) count++; - seq_printf(m, " node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d", + seq_printf(m, " node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d", node->debug_id, (u64)node->ptr, (u64)node->cookie, node->has_strong_ref, node->has_weak_ref, node->local_strong_refs, node->local_weak_refs, - node->internal_strong_refs, count); + node->internal_strong_refs, count, node->tmp_refs); if (count) { seq_puts(m, " proc"); hlist_for_each_entry(ref, &node->refs, node_entry) seq_printf(m, " %d", ref->proc->pid); } seq_puts(m, "\n"); - list_for_each_entry(w, &node->async_todo, entry) - print_binder_work(m, " ", - " pending async transaction", w); + if (node->proc) { + list_for_each_entry(w, &node->async_todo, entry) + print_binder_work_ilocked(m, node->proc, " ", + " pending async transaction", w); + } } -static void print_binder_ref(struct seq_file *m, struct binder_ref *ref) +static void print_binder_ref_olocked(struct seq_file *m, + struct binder_ref *ref) { - seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %p\n", - ref->debug_id, ref->desc, ref->node->proc ? "" : "dead ", - ref->node->debug_id, ref->strong, ref->weak, ref->death); + binder_node_lock(ref->node); + seq_printf(m, " ref %d: desc %d %snode %d s %d w %d d %pK\n", + ref->data.debug_id, ref->data.desc, + ref->node->proc ? "" : "dead ", + ref->node->debug_id, ref->data.strong, + ref->data.weak, ref->death); + binder_node_unlock(ref->node); } static void print_binder_proc(struct seq_file *m, @@ -3971,36 +5692,63 @@ static void print_binder_proc(struct seq_file *m, struct rb_node *n; size_t start_pos = m->count; size_t header_pos; + struct binder_node *last_node = NULL; seq_printf(m, "proc %d\n", proc->pid); seq_printf(m, "context %s\n", proc->context->name); header_pos = m->count; + binder_inner_proc_lock(proc); for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) - print_binder_thread(m, rb_entry(n, struct binder_thread, + print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread, rb_node), print_all); + for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) { struct binder_node *node = rb_entry(n, struct binder_node, rb_node); - if (print_all || node->has_async_transaction) - print_binder_node(m, node); + if (!print_all && !node->has_async_transaction) + continue; + + /* + * take a temporary reference on the node so it + * survives and isn't removed from the tree + * while we print it. + */ + binder_inc_node_tmpref_ilocked(node); + /* Need to drop inner lock to take node lock */ + binder_inner_proc_unlock(proc); + if (last_node) + binder_put_node(last_node); + binder_node_inner_lock(node); + print_binder_node_nilocked(m, node); + binder_node_inner_unlock(node); + last_node = node; + binder_inner_proc_lock(proc); } + binder_inner_proc_unlock(proc); + if (last_node) + binder_put_node(last_node); + if (print_all) { + binder_proc_lock(proc); for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) - print_binder_ref(m, rb_entry(n, struct binder_ref, - rb_node_desc)); + print_binder_ref_olocked(m, rb_entry(n, + struct binder_ref, + rb_node_desc)); + binder_proc_unlock(proc); } - for (n = rb_first(&proc->allocated_buffers); n != NULL; n = rb_next(n)) - print_binder_buffer(m, " buffer", - rb_entry(n, struct binder_buffer, rb_node)); + binder_alloc_print_allocated(m, &proc->alloc); + binder_inner_proc_lock(proc); list_for_each_entry(w, &proc->todo, entry) - print_binder_work(m, " ", " pending transaction", w); + print_binder_work_ilocked(m, proc, " ", + " pending transaction", w); list_for_each_entry(w, &proc->delivered_death, entry) { seq_puts(m, " has delivered dead binder\n"); break; } + binder_inner_proc_unlock(proc); if (!print_all && m->count == header_pos) m->count = start_pos; } @@ -4066,17 +5814,21 @@ static void print_binder_stats(struct seq_file *m, const char *prefix, BUILD_BUG_ON(ARRAY_SIZE(stats->bc) != ARRAY_SIZE(binder_command_strings)); for (i = 0; i < ARRAY_SIZE(stats->bc); i++) { - if (stats->bc[i]) + int temp = atomic_read(&stats->bc[i]); + + if (temp) seq_printf(m, "%s%s: %d\n", prefix, - binder_command_strings[i], stats->bc[i]); + binder_command_strings[i], temp); } BUILD_BUG_ON(ARRAY_SIZE(stats->br) != ARRAY_SIZE(binder_return_strings)); for (i = 0; i < ARRAY_SIZE(stats->br); i++) { - if (stats->br[i]) + int temp = atomic_read(&stats->br[i]); + + if (temp) seq_printf(m, "%s%s: %d\n", prefix, - binder_return_strings[i], stats->br[i]); + binder_return_strings[i], temp); } BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != @@ -4084,11 +5836,15 @@ static void print_binder_stats(struct seq_file *m, const char *prefix, BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) != ARRAY_SIZE(stats->obj_deleted)); for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) { - if (stats->obj_created[i] || stats->obj_deleted[i]) - seq_printf(m, "%s%s: active %d total %d\n", prefix, + int created = atomic_read(&stats->obj_created[i]); + int deleted = atomic_read(&stats->obj_deleted[i]); + + if (created || deleted) + seq_printf(m, "%s%s: active %d total %d\n", + prefix, binder_objstat_strings[i], - stats->obj_created[i] - stats->obj_deleted[i], - stats->obj_created[i]); + created - deleted, + created); } } @@ -4096,254 +5852,253 @@ static void print_binder_proc_stats(struct seq_file *m, struct binder_proc *proc) { struct binder_work *w; + struct binder_thread *thread; struct rb_node *n; - int count, strong, weak; + int count, strong, weak, ready_threads; + size_t free_async_space = + binder_alloc_get_free_async_space(&proc->alloc); seq_printf(m, "proc %d\n", proc->pid); seq_printf(m, "context %s\n", proc->context->name); count = 0; + ready_threads = 0; + binder_inner_proc_lock(proc); for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) count++; + + list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node) + ready_threads++; + seq_printf(m, " threads: %d\n", count); seq_printf(m, " requested threads: %d+%d/%d\n" " ready threads %d\n" " free async space %zd\n", proc->requested_threads, proc->requested_threads_started, proc->max_threads, - proc->ready_threads, proc->free_async_space); + ready_threads, + free_async_space); count = 0; for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) count++; + binder_inner_proc_unlock(proc); seq_printf(m, " nodes: %d\n", count); count = 0; strong = 0; weak = 0; + binder_proc_lock(proc); for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) { struct binder_ref *ref = rb_entry(n, struct binder_ref, rb_node_desc); count++; - strong += ref->strong; - weak += ref->weak; + strong += ref->data.strong; + weak += ref->data.weak; } + binder_proc_unlock(proc); seq_printf(m, " refs: %d s %d w %d\n", count, strong, weak); - count = 0; - for (n = rb_first(&proc->allocated_buffers); n != NULL; n = rb_next(n)) - count++; + count = binder_alloc_get_allocated_count(&proc->alloc); seq_printf(m, " buffers: %d\n", count); + binder_alloc_print_pages(m, &proc->alloc); + count = 0; + binder_inner_proc_lock(proc); list_for_each_entry(w, &proc->todo, entry) { - switch (w->type) { - case BINDER_WORK_TRANSACTION: + if (w->type == BINDER_WORK_TRANSACTION) count++; - break; - default: - break; - } } + binder_inner_proc_unlock(proc); seq_printf(m, " pending transactions: %d\n", count); print_binder_stats(m, " ", &proc->stats); } -static int binder_state_show(struct seq_file *m, void *unused) +int binder_state_show(struct seq_file *m, void *unused) { struct binder_proc *proc; struct binder_node *node; - int do_lock = !binder_debug_no_lock; - - if (do_lock) - binder_lock(__func__); + struct binder_node *last_node = NULL; seq_puts(m, "binder state:\n"); + spin_lock(&binder_dead_nodes_lock); if (!hlist_empty(&binder_dead_nodes)) seq_puts(m, "dead nodes:\n"); - hlist_for_each_entry(node, &binder_dead_nodes, dead_node) - print_binder_node(m, node); + hlist_for_each_entry(node, &binder_dead_nodes, dead_node) { + /* + * take a temporary reference on the node so it + * survives and isn't removed from the list + * while we print it. + */ + node->tmp_refs++; + spin_unlock(&binder_dead_nodes_lock); + if (last_node) + binder_put_node(last_node); + binder_node_lock(node); + print_binder_node_nilocked(m, node); + binder_node_unlock(node); + last_node = node; + spin_lock(&binder_dead_nodes_lock); + } + spin_unlock(&binder_dead_nodes_lock); + if (last_node) + binder_put_node(last_node); + mutex_lock(&binder_procs_lock); hlist_for_each_entry(proc, &binder_procs, proc_node) print_binder_proc(m, proc, 1); - if (do_lock) - binder_unlock(__func__); + mutex_unlock(&binder_procs_lock); + return 0; } -static int binder_stats_show(struct seq_file *m, void *unused) +int binder_stats_show(struct seq_file *m, void *unused) { struct binder_proc *proc; - int do_lock = !binder_debug_no_lock; - - if (do_lock) - binder_lock(__func__); seq_puts(m, "binder stats:\n"); print_binder_stats(m, "", &binder_stats); + mutex_lock(&binder_procs_lock); hlist_for_each_entry(proc, &binder_procs, proc_node) print_binder_proc_stats(m, proc); - if (do_lock) - binder_unlock(__func__); + mutex_unlock(&binder_procs_lock); + return 0; } -static int binder_transactions_show(struct seq_file *m, void *unused) +int binder_transactions_show(struct seq_file *m, void *unused) { struct binder_proc *proc; - int do_lock = !binder_debug_no_lock; - - if (do_lock) - binder_lock(__func__); seq_puts(m, "binder transactions:\n"); + mutex_lock(&binder_procs_lock); hlist_for_each_entry(proc, &binder_procs, proc_node) print_binder_proc(m, proc, 0); - if (do_lock) - binder_unlock(__func__); + mutex_unlock(&binder_procs_lock); + return 0; } -static int binder_proc_show(struct seq_file *m, void *unused) +static int proc_show(struct seq_file *m, void *unused) { struct binder_proc *itr; int pid = (unsigned long)m->private; - int do_lock = !binder_debug_no_lock; - - if (do_lock) - binder_lock(__func__); + mutex_lock(&binder_procs_lock); hlist_for_each_entry(itr, &binder_procs, proc_node) { if (itr->pid == pid) { seq_puts(m, "binder proc state:\n"); print_binder_proc(m, itr, 1); } } - if (do_lock) - binder_unlock(__func__); + mutex_unlock(&binder_procs_lock); + return 0; } static void print_binder_transaction_log_entry(struct seq_file *m, struct binder_transaction_log_entry *e) { + int debug_id = READ_ONCE(e->debug_id_done); + /* + * read barrier to guarantee debug_id_done read before + * we print the log values + */ + smp_rmb(); seq_printf(m, - "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d\n", + "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d", e->debug_id, (e->call_type == 2) ? "reply" : ((e->call_type == 1) ? "async" : "call "), e->from_proc, e->from_thread, e->to_proc, e->to_thread, e->context_name, - e->to_node, e->target_handle, e->data_size, e->offsets_size); + e->to_node, e->target_handle, e->data_size, e->offsets_size, + e->return_error, e->return_error_param, + e->return_error_line); + /* + * read-barrier to guarantee read of debug_id_done after + * done printing the fields of the entry + */ + smp_rmb(); + seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ? + "\n" : " (incomplete)\n"); } -static int binder_transaction_log_show(struct seq_file *m, void *unused) +int binder_transaction_log_show(struct seq_file *m, void *unused) { struct binder_transaction_log *log = m->private; + unsigned int log_cur = atomic_read(&log->cur); + unsigned int count; + unsigned int cur; int i; - if (log->full) { - for (i = log->next; i < ARRAY_SIZE(log->entry); i++) - print_binder_transaction_log_entry(m, &log->entry[i]); + count = log_cur + 1; + cur = count < ARRAY_SIZE(log->entry) && !log->full ? + 0 : count % ARRAY_SIZE(log->entry); + if (count > ARRAY_SIZE(log->entry) || log->full) + count = ARRAY_SIZE(log->entry); + for (i = 0; i < count; i++) { + unsigned int index = cur++ % ARRAY_SIZE(log->entry); + + print_binder_transaction_log_entry(m, &log->entry[index]); } - for (i = 0; i < log->next; i++) - print_binder_transaction_log_entry(m, &log->entry[i]); return 0; } -static const struct file_operations binder_fops = { +const struct file_operations binder_fops = { .owner = THIS_MODULE, .poll = binder_poll, .unlocked_ioctl = binder_ioctl, - .compat_ioctl = binder_ioctl, + .compat_ioctl = compat_ptr_ioctl, .mmap = binder_mmap, .open = binder_open, .flush = binder_flush, .release = binder_release, }; -BINDER_DEBUG_ENTRY(state); -BINDER_DEBUG_ENTRY(stats); -BINDER_DEBUG_ENTRY(transactions); -BINDER_DEBUG_ENTRY(transaction_log); - -static struct class *binder_class; - -static void binder_device_release(struct device *dev) -{ -} - -static int __init init_binder_device(int idx) +static int __init init_binder_device(const char *name) { int ret; - char *name; - dev_t devnr; struct binder_device *binder_device; - /* strlen("binder") - * + - * maximum length of 64 bit int as string - */ - char numstr[6 + 21] = "binder"; binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL); if (!binder_device) return -ENOMEM; - cdev_init(&binder_device->cdev, &binder_fops); - binder_device->cdev.owner = THIS_MODULE; + binder_device->miscdev.fops = &binder_fops; + binder_device->miscdev.minor = MISC_DYNAMIC_MINOR; + binder_device->miscdev.name = name; - devnr = MKDEV(BINDER_DKMS_MAJOR, idx); - ret = cdev_add(&binder_device->cdev, devnr, 1); - if (ret) { - kfree(binder_device); - return ret; - } - - if (binder_devices_param > 1) - ret = snprintf(numstr, sizeof(numstr), "binder%d", idx); - if (ret < 0 || (size_t)ret >= sizeof(numstr)) { - cdev_del(&binder_device->cdev); - kfree(binder_device); - return -EIO; - } - - name = kzalloc(strlen(numstr) + 1, GFP_KERNEL); - if (!name) { - cdev_del(&binder_device->cdev); - kfree(binder_device); - return -ENOMEM; - } - strcpy(name, numstr); - binder_device->context.name = name; + refcount_set(&binder_device->ref, 1); binder_device->context.binder_context_mgr_uid = INVALID_UID; + binder_device->context.name = name; + mutex_init(&binder_device->context.context_mgr_node_lock); - binder_device->class_dev.devt = binder_device->cdev.dev; - binder_device->class_dev.class = binder_class; - binder_device->class_dev.release = binder_device_release; - dev_set_name(&binder_device->class_dev, "%s", name); - ret = device_register(&binder_device->class_dev); - if (ret) { - cdev_del(&binder_device->cdev); + ret = misc_register(&binder_device->miscdev); + if (ret < 0) { kfree(binder_device); - kfree(name); return ret; } - mutex_lock(&binder_devices_mtx); hlist_add_head(&binder_device->hlist, &binder_devices); - mutex_unlock(&binder_devices_mtx); - return 0; + return ret; } static int __init binder_init(void) { - int i, ret; + int ret; + char *device_name, *device_tmp; struct binder_device *device; struct hlist_node *tmp; + char *device_names = NULL; - if (binder_devices_param <= 0 || - binder_devices_param > BINDER_DKMS_MAX_MINOR) - return -EINVAL; + ret = binder_alloc_shrinker_init(); + if (ret) + return ret; + + atomic_set(&binder_transaction_log.cur, ~0U); + atomic_set(&binder_transaction_log_failed.cur, ~0U); binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL); if (binder_debugfs_dir_entry_root) @@ -4352,95 +6107,93 @@ static int __init binder_init(void) if (binder_debugfs_dir_entry_root) { debugfs_create_file("state", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_state_fops); debugfs_create_file("stats", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_stats_fops); debugfs_create_file("transactions", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_transactions_fops); debugfs_create_file("transaction_log", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, &binder_transaction_log, &binder_transaction_log_fops); debugfs_create_file("failed_transaction_log", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, &binder_transaction_log_failed, &binder_transaction_log_fops); } - ret = register_chrdev_region(MKDEV(BINDER_DKMS_MAJOR, 0), - BINDER_DKMS_MAX_MINOR, "binder"); - if (ret) - goto on_error_remove_debugfs; + if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) && + strcmp(binder_devices_param, "") != 0) { + /* + * Copy the module_parameter string, because we don't want to + * tokenize it in-place. + */ + device_names = kstrdup(binder_devices_param, GFP_KERNEL); + if (!device_names) { + ret = -ENOMEM; + goto err_alloc_device_names_failed; + } - binder_class = class_create(THIS_MODULE, "binder"); - if (IS_ERR(binder_class)) - goto on_error_unregister_chrdev_region; - - for (i = 0; i < binder_devices_param; i++) { - ret = init_binder_device(i); - if (ret) - goto err_init_binder_device_failed; + device_tmp = device_names; + while ((device_name = strsep(&device_tmp, ","))) { + ret = init_binder_device(device_name); + if (ret) + goto err_init_binder_device_failed; + } } + ret = init_binderfs(); + if (ret) + goto err_init_binder_device_failed; + return ret; err_init_binder_device_failed: - mutex_lock(&binder_devices_mtx); hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) { - cdev_del(&device->cdev); - device_unregister(&device->class_dev); - kfree(device->context.name); + misc_deregister(&device->miscdev); hlist_del(&device->hlist); kfree(device); } - mutex_unlock(&binder_devices_mtx); - class_destroy(binder_class); -on_error_unregister_chrdev_region: - unregister_chrdev_region(MKDEV(BINDER_DKMS_MAJOR, 0), - BINDER_DKMS_MAX_MINOR); + kfree(device_names); -on_error_remove_debugfs: +err_alloc_device_names_failed: debugfs_remove_recursive(binder_debugfs_dir_entry_root); - return -1; + return ret; } +module_init(binder_init); + static void __exit binder_exit(void) { struct binder_device *device; struct hlist_node *tmp; - mutex_lock(&binder_devices_mtx); + exit_binderfs(); + hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) { - cdev_del(&device->cdev); - device_unregister(&device->class_dev); - kfree(device->context.name); + misc_deregister(&device->miscdev); hlist_del(&device->hlist); kfree(device); } - mutex_unlock(&binder_devices_mtx); - - class_destroy(binder_class); - - unregister_chrdev_region(MKDEV(BINDER_DKMS_MAJOR, 0), - BINDER_DKMS_MAX_MINOR); debugfs_remove_recursive(binder_debugfs_dir_entry_root); + + binder_alloc_shrinker_exit(); } -module_init(binder_init); module_exit(binder_exit); #define CREATE_TRACE_POINTS diff --git a/binder/binder.h b/binder/binder.h index 51f891f..08df91e 100644 --- a/binder/binder.h +++ b/binder/binder.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* * Copyright (C) 2008 Google, Inc. * @@ -20,6 +21,8 @@ #ifndef _UAPI_LINUX_BINDER_H #define _UAPI_LINUX_BINDER_H +#define BINDER_IPC_32BIT 1 + #include #include @@ -40,6 +43,14 @@ enum { enum { FLAT_BINDER_FLAG_PRIORITY_MASK = 0xff, FLAT_BINDER_FLAG_ACCEPTS_FDS = 0x100, + + /** + * @FLAT_BINDER_FLAG_TXN_SECURITY_CTX: request security contexts + * + * Only when set, causes senders to include their security + * context + */ + FLAT_BINDER_FLAG_TXN_SECURITY_CTX = 0x1000, }; #ifdef BINDER_IPC_32BIT @@ -132,6 +143,7 @@ enum { /* struct binder_fd_array_object - object describing an array of fds in a buffer * @hdr: common header structure + * @pad: padding to ensure correct alignment * @num_fds: number of file descriptors in the buffer * @parent: index in offset array to buffer holding the fd array * @parent_offset: start offset of fd array in the buffer @@ -152,6 +164,7 @@ enum { */ struct binder_fd_array_object { struct binder_object_header hdr; + __u32 pad; binder_size_t num_fds; binder_size_t parent; binder_size_t parent_offset; @@ -184,6 +197,28 @@ struct binder_version { #define BINDER_CURRENT_PROTOCOL_VERSION 8 #endif +/* + * Use with BINDER_GET_NODE_DEBUG_INFO, driver reads ptr, writes to all fields. + * Set ptr to NULL for the first call to get the info for the first node, and + * then repeat the call passing the previously returned value to get the next + * nodes. ptr will be 0 when there are no more nodes. + */ +struct binder_node_debug_info { + binder_uintptr_t ptr; + binder_uintptr_t cookie; + __u32 has_strong_ref; + __u32 has_weak_ref; +}; + +struct binder_node_info_for_ref { + __u32 handle; + __u32 strong_count; + __u32 weak_count; + __u32 reserved1; + __u32 reserved2; + __u32 reserved3; +}; + #define BINDER_WRITE_READ _IOWR('b', 1, struct binder_write_read) #define BINDER_SET_IDLE_TIMEOUT _IOW('b', 3, __s64) #define BINDER_SET_MAX_THREADS _IOW('b', 5, __u32) @@ -191,6 +226,9 @@ struct binder_version { #define BINDER_SET_CONTEXT_MGR _IOW('b', 7, __s32) #define BINDER_THREAD_EXIT _IOW('b', 8, __s32) #define BINDER_VERSION _IOWR('b', 9, struct binder_version) +#define BINDER_GET_NODE_DEBUG_INFO _IOWR('b', 11, struct binder_node_debug_info) +#define BINDER_GET_NODE_INFO_FOR_REF _IOWR('b', 12, struct binder_node_info_for_ref) +#define BINDER_SET_CONTEXT_MGR_EXT _IOW('b', 13, struct flat_binder_object) /* * NOTE: Two special error codes you should check for when calling @@ -212,6 +250,7 @@ enum transaction_flags { TF_ROOT_OBJECT = 0x04, /* contents are the component's root object */ TF_STATUS_CODE = 0x08, /* contents are a 32-bit status code */ TF_ACCEPT_FDS = 0x10, /* allow replies with file descriptors */ + TF_CLEAR_BUF = 0x20, /* clear buffer on txn complete */ }; struct binder_transaction_data { @@ -249,6 +288,11 @@ struct binder_transaction_data { } data; }; +struct binder_transaction_data_secctx { + struct binder_transaction_data transaction_data; + binder_uintptr_t secctx; +}; + struct binder_transaction_data_sg { struct binder_transaction_data transaction_data; binder_size_t buffers_size; @@ -284,6 +328,11 @@ enum binder_driver_return_protocol { BR_OK = _IO('r', 1), /* No parameters! */ + BR_TRANSACTION_SEC_CTX = _IOR('r', 2, + struct binder_transaction_data_secctx), + /* + * binder_transaction_data_secctx: the received command. + */ BR_TRANSACTION = _IOR('r', 2, struct binder_transaction_data), BR_REPLY = _IOR('r', 3, struct binder_transaction_data), /* @@ -358,7 +407,7 @@ enum binder_driver_return_protocol { BR_FAILED_REPLY = _IO('r', 17), /* - * The the last transaction (either a bcTRANSACTION or + * The last transaction (either a bcTRANSACTION or * a bcATTEMPT_ACQUIRE) failed (e.g. out of memory). No parameters. */ }; diff --git a/binder/binder_alloc.c b/binder/binder_alloc.c new file mode 100644 index 0000000..61dd545 --- /dev/null +++ b/binder/binder_alloc.c @@ -0,0 +1,1295 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* binder_alloc.c + * + * Android IPC Subsystem + * + * Copyright (C) 2007-2017 Google, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "binder_alloc.h" +#include "binder_trace.h" + +struct list_lru binder_alloc_lru; + +static DEFINE_MUTEX(binder_alloc_mmap_lock); + +enum { + BINDER_DEBUG_USER_ERROR = 1U << 0, + BINDER_DEBUG_OPEN_CLOSE = 1U << 1, + BINDER_DEBUG_BUFFER_ALLOC = 1U << 2, + BINDER_DEBUG_BUFFER_ALLOC_ASYNC = 1U << 3, +}; +static uint32_t binder_alloc_debug_mask = BINDER_DEBUG_USER_ERROR; + +module_param_named(debug_mask, binder_alloc_debug_mask, + uint, 0644); + +#define binder_alloc_debug(mask, x...) \ + do { \ + if (binder_alloc_debug_mask & mask) \ + pr_info_ratelimited(x); \ + } while (0) + +static struct binder_buffer *binder_buffer_next(struct binder_buffer *buffer) +{ + return list_entry(buffer->entry.next, struct binder_buffer, entry); +} + +static struct binder_buffer *binder_buffer_prev(struct binder_buffer *buffer) +{ + return list_entry(buffer->entry.prev, struct binder_buffer, entry); +} + +static size_t binder_alloc_buffer_size(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + if (list_is_last(&buffer->entry, &alloc->buffers)) + return alloc->buffer + alloc->buffer_size - buffer->user_data; + return binder_buffer_next(buffer)->user_data - buffer->user_data; +} + +static void binder_insert_free_buffer(struct binder_alloc *alloc, + struct binder_buffer *new_buffer) +{ + struct rb_node **p = &alloc->free_buffers.rb_node; + struct rb_node *parent = NULL; + struct binder_buffer *buffer; + size_t buffer_size; + size_t new_buffer_size; + + BUG_ON(!new_buffer->free); + + new_buffer_size = binder_alloc_buffer_size(alloc, new_buffer); + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: add free buffer, size %zd, at %pK\n", + alloc->pid, new_buffer_size, new_buffer); + + while (*p) { + parent = *p; + buffer = rb_entry(parent, struct binder_buffer, rb_node); + BUG_ON(!buffer->free); + + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + if (new_buffer_size < buffer_size) + p = &parent->rb_left; + else + p = &parent->rb_right; + } + rb_link_node(&new_buffer->rb_node, parent, p); + rb_insert_color(&new_buffer->rb_node, &alloc->free_buffers); +} + +static void binder_insert_allocated_buffer_locked( + struct binder_alloc *alloc, struct binder_buffer *new_buffer) +{ + struct rb_node **p = &alloc->allocated_buffers.rb_node; + struct rb_node *parent = NULL; + struct binder_buffer *buffer; + + BUG_ON(new_buffer->free); + + while (*p) { + parent = *p; + buffer = rb_entry(parent, struct binder_buffer, rb_node); + BUG_ON(buffer->free); + + if (new_buffer->user_data < buffer->user_data) + p = &parent->rb_left; + else if (new_buffer->user_data > buffer->user_data) + p = &parent->rb_right; + else + BUG(); + } + rb_link_node(&new_buffer->rb_node, parent, p); + rb_insert_color(&new_buffer->rb_node, &alloc->allocated_buffers); +} + +static struct binder_buffer *binder_alloc_prepare_to_free_locked( + struct binder_alloc *alloc, + uintptr_t user_ptr) +{ + struct rb_node *n = alloc->allocated_buffers.rb_node; + struct binder_buffer *buffer; + void __user *uptr; + + uptr = (void __user *)user_ptr; + + while (n) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + BUG_ON(buffer->free); + + if (uptr < buffer->user_data) + n = n->rb_left; + else if (uptr > buffer->user_data) + n = n->rb_right; + else { + /* + * Guard against user threads attempting to + * free the buffer when in use by kernel or + * after it's already been freed. + */ + if (!buffer->allow_user_free) + return ERR_PTR(-EPERM); + buffer->allow_user_free = 0; + return buffer; + } + } + return NULL; +} + +/** + * binder_alloc_prepare_to_free() - get buffer given user ptr + * @alloc: binder_alloc for this proc + * @user_ptr: User pointer to buffer data + * + * Validate userspace pointer to buffer data and return buffer corresponding to + * that user pointer. Search the rb tree for buffer that matches user data + * pointer. + * + * Return: Pointer to buffer or NULL + */ +struct binder_buffer *binder_alloc_prepare_to_free(struct binder_alloc *alloc, + uintptr_t user_ptr) +{ + struct binder_buffer *buffer; + + mutex_lock(&alloc->mutex); + buffer = binder_alloc_prepare_to_free_locked(alloc, user_ptr); + mutex_unlock(&alloc->mutex); + return buffer; +} + +static int binder_update_page_range(struct binder_alloc *alloc, int allocate, + void __user *start, void __user *end) +{ + void __user *page_addr; + unsigned long user_page_addr; + struct binder_lru_page *page; + struct vm_area_struct *vma = NULL; + struct mm_struct *mm = NULL; + bool need_mm = false; + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: %s pages %pK-%pK\n", alloc->pid, + allocate ? "allocate" : "free", start, end); + + if (end <= start) + return 0; + + trace_binder_update_page_range(alloc, allocate, start, end); + + if (allocate == 0) + goto free_range; + + for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { + page = &alloc->pages[(page_addr - alloc->buffer) / PAGE_SIZE]; + if (!page->page_ptr) { + need_mm = true; + break; + } + } + + if (need_mm && mmget_not_zero(alloc->vma_vm_mm)) + mm = alloc->vma_vm_mm; + + if (mm) { + mmap_read_lock(mm); + vma = alloc->vma; + } + + if (!vma && need_mm) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf failed to map pages in userspace, no vma\n", + alloc->pid); + goto err_no_vma; + } + + for (page_addr = start; page_addr < end; page_addr += PAGE_SIZE) { + int ret; + bool on_lru; + size_t index; + + index = (page_addr - alloc->buffer) / PAGE_SIZE; + page = &alloc->pages[index]; + + if (page->page_ptr) { + trace_binder_alloc_lru_start(alloc, index); + + on_lru = list_lru_del(&binder_alloc_lru, &page->lru); + WARN_ON(!on_lru); + + trace_binder_alloc_lru_end(alloc, index); + continue; + } + + if (WARN_ON(!vma)) + goto err_page_ptr_cleared; + + trace_binder_alloc_page_start(alloc, index); + page->page_ptr = alloc_page(GFP_KERNEL | + __GFP_HIGHMEM | + __GFP_ZERO); + if (!page->page_ptr) { + pr_err("%d: binder_alloc_buf failed for page at %pK\n", + alloc->pid, page_addr); + goto err_alloc_page_failed; + } + page->alloc = alloc; + INIT_LIST_HEAD(&page->lru); + + user_page_addr = (uintptr_t)page_addr; + ret = vm_insert_page(vma, user_page_addr, page[0].page_ptr); + if (ret) { + pr_err("%d: binder_alloc_buf failed to map page at %lx in userspace\n", + alloc->pid, user_page_addr); + goto err_vm_insert_page_failed; + } + + if (index + 1 > alloc->pages_high) + alloc->pages_high = index + 1; + + trace_binder_alloc_page_end(alloc, index); + } + if (mm) { + mmap_read_unlock(mm); + mmput(mm); + } + return 0; + +free_range: + for (page_addr = end - PAGE_SIZE; 1; page_addr -= PAGE_SIZE) { + bool ret; + size_t index; + + index = (page_addr - alloc->buffer) / PAGE_SIZE; + page = &alloc->pages[index]; + + trace_binder_free_lru_start(alloc, index); + + ret = list_lru_add(&binder_alloc_lru, &page->lru); + WARN_ON(!ret); + + trace_binder_free_lru_end(alloc, index); + if (page_addr == start) + break; + continue; + +err_vm_insert_page_failed: + __free_page(page->page_ptr); + page->page_ptr = NULL; +err_alloc_page_failed: +err_page_ptr_cleared: + if (page_addr == start) + break; + } +err_no_vma: + if (mm) { + mmap_read_unlock(mm); + mmput(mm); + } + return vma ? -ENOMEM : -ESRCH; +} + + +static inline void binder_alloc_set_vma(struct binder_alloc *alloc, + struct vm_area_struct *vma) +{ + if (vma) + alloc->vma_vm_mm = vma->vm_mm; + /* + * If we see alloc->vma is not NULL, buffer data structures set up + * completely. Look at smp_rmb side binder_alloc_get_vma. + * We also want to guarantee new alloc->vma_vm_mm is always visible + * if alloc->vma is set. + */ + smp_wmb(); + alloc->vma = vma; +} + +static inline struct vm_area_struct *binder_alloc_get_vma( + struct binder_alloc *alloc) +{ + struct vm_area_struct *vma = NULL; + + if (alloc->vma) { + /* Look at description in binder_alloc_set_vma */ + smp_rmb(); + vma = alloc->vma; + } + return vma; +} + +static void debug_low_async_space_locked(struct binder_alloc *alloc, int pid) +{ + /* + * Find the amount and size of buffers allocated by the current caller; + * The idea is that once we cross the threshold, whoever is responsible + * for the low async space is likely to try to send another async txn, + * and at some point we'll catch them in the act. This is more efficient + * than keeping a map per pid. + */ + struct rb_node *n; + struct binder_buffer *buffer; + size_t total_alloc_size = 0; + size_t num_buffers = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + if (buffer->pid != pid) + continue; + if (!buffer->async_transaction) + continue; + total_alloc_size += binder_alloc_buffer_size(alloc, buffer) + + sizeof(struct binder_buffer); + num_buffers++; + } + + /* + * Warn if this pid has more than 50 transactions, or more than 50% of + * async space (which is 25% of total buffer size). + */ + if (num_buffers > 50 || total_alloc_size > alloc->buffer_size / 4) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: pid %d spamming oneway? %zd buffers allocated for a total size of %zd\n", + alloc->pid, pid, num_buffers, total_alloc_size); + } +} + +static struct binder_buffer *binder_alloc_new_buf_locked( + struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid) +{ + struct rb_node *n = alloc->free_buffers.rb_node; + struct binder_buffer *buffer; + size_t buffer_size; + struct rb_node *best_fit = NULL; + void __user *has_page_addr; + void __user *end_page_addr; + size_t size, data_offsets_size; + int ret; + + if (!binder_alloc_get_vma(alloc)) { + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf, no vma\n", + alloc->pid); + return ERR_PTR(-ESRCH); + } + + data_offsets_size = ALIGN(data_size, sizeof(void *)) + + ALIGN(offsets_size, sizeof(void *)); + + if (data_offsets_size < data_size || data_offsets_size < offsets_size) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: got transaction with invalid size %zd-%zd\n", + alloc->pid, data_size, offsets_size); + return ERR_PTR(-EINVAL); + } + size = data_offsets_size + ALIGN(extra_buffers_size, sizeof(void *)); + if (size < data_offsets_size || size < extra_buffers_size) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: got transaction with invalid extra_buffers_size %zd\n", + alloc->pid, extra_buffers_size); + return ERR_PTR(-EINVAL); + } + if (is_async && + alloc->free_async_space < size + sizeof(struct binder_buffer)) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd failed, no async space left\n", + alloc->pid, size); + return ERR_PTR(-ENOSPC); + } + + /* Pad 0-size buffers so they get assigned unique addresses */ + size = max(size, sizeof(void *)); + + while (n) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + BUG_ON(!buffer->free); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + if (size < buffer_size) { + best_fit = n; + n = n->rb_left; + } else if (size > buffer_size) + n = n->rb_right; + else { + best_fit = n; + break; + } + } + if (best_fit == NULL) { + size_t allocated_buffers = 0; + size_t largest_alloc_size = 0; + size_t total_alloc_size = 0; + size_t free_buffers = 0; + size_t largest_free_size = 0; + size_t total_free_size = 0; + + for (n = rb_first(&alloc->allocated_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + allocated_buffers++; + total_alloc_size += buffer_size; + if (buffer_size > largest_alloc_size) + largest_alloc_size = buffer_size; + } + for (n = rb_first(&alloc->free_buffers); n != NULL; + n = rb_next(n)) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + free_buffers++; + total_free_size += buffer_size; + if (buffer_size > largest_free_size) + largest_free_size = buffer_size; + } + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%d: binder_alloc_buf size %zd failed, no address space\n", + alloc->pid, size); + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "allocated: %zd (num: %zd largest: %zd), free: %zd (num: %zd largest: %zd)\n", + total_alloc_size, allocated_buffers, + largest_alloc_size, total_free_size, + free_buffers, largest_free_size); + return ERR_PTR(-ENOSPC); + } + if (n == NULL) { + buffer = rb_entry(best_fit, struct binder_buffer, rb_node); + buffer_size = binder_alloc_buffer_size(alloc, buffer); + } + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd got buffer %pK size %zd\n", + alloc->pid, size, buffer, buffer_size); + + has_page_addr = (void __user *) + (((uintptr_t)buffer->user_data + buffer_size) & PAGE_MASK); + WARN_ON(n && buffer_size != size); + end_page_addr = + (void __user *)PAGE_ALIGN((uintptr_t)buffer->user_data + size); + if (end_page_addr > has_page_addr) + end_page_addr = has_page_addr; + ret = binder_update_page_range(alloc, 1, (void __user *) + PAGE_ALIGN((uintptr_t)buffer->user_data), end_page_addr); + if (ret) + return ERR_PTR(ret); + + if (buffer_size != size) { + struct binder_buffer *new_buffer; + + new_buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!new_buffer) { + pr_err("%s: %d failed to alloc new buffer struct\n", + __func__, alloc->pid); + goto err_alloc_buf_struct_failed; + } + new_buffer->user_data = (u8 __user *)buffer->user_data + size; + list_add(&new_buffer->entry, &buffer->entry); + new_buffer->free = 1; + binder_insert_free_buffer(alloc, new_buffer); + } + + rb_erase(best_fit, &alloc->free_buffers); + buffer->free = 0; + buffer->allow_user_free = 0; + binder_insert_allocated_buffer_locked(alloc, buffer); + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_alloc_buf size %zd got %pK\n", + alloc->pid, size, buffer); + buffer->data_size = data_size; + buffer->offsets_size = offsets_size; + buffer->async_transaction = is_async; + buffer->extra_buffers_size = extra_buffers_size; + buffer->pid = pid; + if (is_async) { + alloc->free_async_space -= size + sizeof(struct binder_buffer); + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, + "%d: binder_alloc_buf size %zd async free %zd\n", + alloc->pid, size, alloc->free_async_space); + if (alloc->free_async_space < alloc->buffer_size / 10) { + /* + * Start detecting spammers once we have less than 20% + * of async space left (which is less than 10% of total + * buffer size). + */ + debug_low_async_space_locked(alloc, pid); + } + } + return buffer; + +err_alloc_buf_struct_failed: + binder_update_page_range(alloc, 0, (void __user *) + PAGE_ALIGN((uintptr_t)buffer->user_data), + end_page_addr); + return ERR_PTR(-ENOMEM); +} + +/** + * binder_alloc_new_buf() - Allocate a new binder buffer + * @alloc: binder_alloc for this proc + * @data_size: size of user data buffer + * @offsets_size: user specified buffer offset + * @extra_buffers_size: size of extra space for meta-data (eg, security context) + * @is_async: buffer for async transaction + * @pid: pid to attribute allocation to (used for debugging) + * + * Allocate a new buffer given the requested sizes. Returns + * the kernel version of the buffer pointer. The size allocated + * is the sum of the three given sizes (each rounded up to + * pointer-sized boundary) + * + * Return: The allocated buffer or %NULL if error + */ +struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid) +{ + struct binder_buffer *buffer; + + mutex_lock(&alloc->mutex); + buffer = binder_alloc_new_buf_locked(alloc, data_size, offsets_size, + extra_buffers_size, is_async, pid); + mutex_unlock(&alloc->mutex); + return buffer; +} + +static void __user *buffer_start_page(struct binder_buffer *buffer) +{ + return (void __user *)((uintptr_t)buffer->user_data & PAGE_MASK); +} + +static void __user *prev_buffer_end_page(struct binder_buffer *buffer) +{ + return (void __user *) + (((uintptr_t)(buffer->user_data) - 1) & PAGE_MASK); +} + +static void binder_delete_free_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + struct binder_buffer *prev, *next = NULL; + bool to_free = true; + + BUG_ON(alloc->buffers.next == &buffer->entry); + prev = binder_buffer_prev(buffer); + BUG_ON(!prev->free); + if (prev_buffer_end_page(prev) == buffer_start_page(buffer)) { + to_free = false; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK share page with %pK\n", + alloc->pid, buffer->user_data, + prev->user_data); + } + + if (!list_is_last(&buffer->entry, &alloc->buffers)) { + next = binder_buffer_next(buffer); + if (buffer_start_page(next) == buffer_start_page(buffer)) { + to_free = false; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK share page with %pK\n", + alloc->pid, + buffer->user_data, + next->user_data); + } + } + + if (PAGE_ALIGNED(buffer->user_data)) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer start %pK is page aligned\n", + alloc->pid, buffer->user_data); + to_free = false; + } + + if (to_free) { + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: merge free, buffer %pK do not share page with %pK or %pK\n", + alloc->pid, buffer->user_data, + prev->user_data, + next ? next->user_data : NULL); + binder_update_page_range(alloc, 0, buffer_start_page(buffer), + buffer_start_page(buffer) + PAGE_SIZE); + } + list_del(&buffer->entry); + kfree(buffer); +} + +static void binder_free_buf_locked(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + size_t size, buffer_size; + + buffer_size = binder_alloc_buffer_size(alloc, buffer); + + size = ALIGN(buffer->data_size, sizeof(void *)) + + ALIGN(buffer->offsets_size, sizeof(void *)) + + ALIGN(buffer->extra_buffers_size, sizeof(void *)); + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%d: binder_free_buf %pK size %zd buffer_size %zd\n", + alloc->pid, buffer, size, buffer_size); + + BUG_ON(buffer->free); + BUG_ON(size > buffer_size); + BUG_ON(buffer->transaction != NULL); + BUG_ON(buffer->user_data < alloc->buffer); + BUG_ON(buffer->user_data > alloc->buffer + alloc->buffer_size); + + if (buffer->async_transaction) { + alloc->free_async_space += size + sizeof(struct binder_buffer); + + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC_ASYNC, + "%d: binder_free_buf size %zd async free %zd\n", + alloc->pid, size, alloc->free_async_space); + } + + binder_update_page_range(alloc, 0, + (void __user *)PAGE_ALIGN((uintptr_t)buffer->user_data), + (void __user *)(((uintptr_t) + buffer->user_data + buffer_size) & PAGE_MASK)); + + rb_erase(&buffer->rb_node, &alloc->allocated_buffers); + buffer->free = 1; + if (!list_is_last(&buffer->entry, &alloc->buffers)) { + struct binder_buffer *next = binder_buffer_next(buffer); + + if (next->free) { + rb_erase(&next->rb_node, &alloc->free_buffers); + binder_delete_free_buffer(alloc, next); + } + } + if (alloc->buffers.next != &buffer->entry) { + struct binder_buffer *prev = binder_buffer_prev(buffer); + + if (prev->free) { + binder_delete_free_buffer(alloc, buffer); + rb_erase(&prev->rb_node, &alloc->free_buffers); + buffer = prev; + } + } + binder_insert_free_buffer(alloc, buffer); +} + +static void binder_alloc_clear_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer); +/** + * binder_alloc_free_buf() - free a binder buffer + * @alloc: binder_alloc for this proc + * @buffer: kernel pointer to buffer + * + * Free the buffer allocated via binder_alloc_new_buf() + */ +void binder_alloc_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + /* + * We could eliminate the call to binder_alloc_clear_buf() + * from binder_alloc_deferred_release() by moving this to + * binder_alloc_free_buf_locked(). However, that could + * increase contention for the alloc mutex if clear_on_free + * is used frequently for large buffers. The mutex is not + * needed for correctness here. + */ + if (buffer->clear_on_free) { + binder_alloc_clear_buf(alloc, buffer); + buffer->clear_on_free = false; + } + mutex_lock(&alloc->mutex); + binder_free_buf_locked(alloc, buffer); + mutex_unlock(&alloc->mutex); +} + +/** + * binder_alloc_mmap_handler() - map virtual address space for proc + * @alloc: alloc structure for this proc + * @vma: vma passed to mmap() + * + * Called by binder_mmap() to initialize the space specified in + * vma for allocating binder buffers + * + * Return: + * 0 = success + * -EBUSY = address space already mapped + * -ENOMEM = failed to map memory to given address space + */ +int binder_alloc_mmap_handler(struct binder_alloc *alloc, + struct vm_area_struct *vma) +{ + int ret; + const char *failure_string; + struct binder_buffer *buffer; + + mutex_lock(&binder_alloc_mmap_lock); + if (alloc->buffer_size) { + ret = -EBUSY; + failure_string = "already mapped"; + goto err_already_mapped; + } + alloc->buffer_size = min_t(unsigned long, vma->vm_end - vma->vm_start, + SZ_4M); + mutex_unlock(&binder_alloc_mmap_lock); + + alloc->buffer = (void __user *)vma->vm_start; + + alloc->pages = kcalloc(alloc->buffer_size / PAGE_SIZE, + sizeof(alloc->pages[0]), + GFP_KERNEL); + if (alloc->pages == NULL) { + ret = -ENOMEM; + failure_string = "alloc page array"; + goto err_alloc_pages_failed; + } + + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); + if (!buffer) { + ret = -ENOMEM; + failure_string = "alloc buffer struct"; + goto err_alloc_buf_struct_failed; + } + + buffer->user_data = alloc->buffer; + list_add(&buffer->entry, &alloc->buffers); + buffer->free = 1; + binder_insert_free_buffer(alloc, buffer); + alloc->free_async_space = alloc->buffer_size / 2; + binder_alloc_set_vma(alloc, vma); + mmgrab(alloc->vma_vm_mm); + + return 0; + +err_alloc_buf_struct_failed: + kfree(alloc->pages); + alloc->pages = NULL; +err_alloc_pages_failed: + alloc->buffer = NULL; + mutex_lock(&binder_alloc_mmap_lock); + alloc->buffer_size = 0; +err_already_mapped: + mutex_unlock(&binder_alloc_mmap_lock); + binder_alloc_debug(BINDER_DEBUG_USER_ERROR, + "%s: %d %lx-%lx %s failed %d\n", __func__, + alloc->pid, vma->vm_start, vma->vm_end, + failure_string, ret); + return ret; +} + + +void binder_alloc_deferred_release(struct binder_alloc *alloc) +{ + struct rb_node *n; + int buffers, page_count; + struct binder_buffer *buffer; + + buffers = 0; + mutex_lock(&alloc->mutex); + BUG_ON(alloc->vma); + + while ((n = rb_first(&alloc->allocated_buffers))) { + buffer = rb_entry(n, struct binder_buffer, rb_node); + + /* Transaction should already have been freed */ + BUG_ON(buffer->transaction); + + if (buffer->clear_on_free) { + binder_alloc_clear_buf(alloc, buffer); + buffer->clear_on_free = false; + } + binder_free_buf_locked(alloc, buffer); + buffers++; + } + + while (!list_empty(&alloc->buffers)) { + buffer = list_first_entry(&alloc->buffers, + struct binder_buffer, entry); + WARN_ON(!buffer->free); + + list_del(&buffer->entry); + WARN_ON_ONCE(!list_empty(&alloc->buffers)); + kfree(buffer); + } + + page_count = 0; + if (alloc->pages) { + int i; + + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + void __user *page_addr; + bool on_lru; + + if (!alloc->pages[i].page_ptr) + continue; + + on_lru = list_lru_del(&binder_alloc_lru, + &alloc->pages[i].lru); + page_addr = alloc->buffer + i * PAGE_SIZE; + binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC, + "%s: %d: page %d at %pK %s\n", + __func__, alloc->pid, i, page_addr, + on_lru ? "on lru" : "active"); + __free_page(alloc->pages[i].page_ptr); + page_count++; + } + kfree(alloc->pages); + } + mutex_unlock(&alloc->mutex); + if (alloc->vma_vm_mm) + mmdrop(alloc->vma_vm_mm); + + binder_alloc_debug(BINDER_DEBUG_OPEN_CLOSE, + "%s: %d buffers %d, pages %d\n", + __func__, alloc->pid, buffers, page_count); +} + +static void print_binder_buffer(struct seq_file *m, const char *prefix, + struct binder_buffer *buffer) +{ + seq_printf(m, "%s %d: %pK size %zd:%zd:%zd %s\n", + prefix, buffer->debug_id, buffer->user_data, + buffer->data_size, buffer->offsets_size, + buffer->extra_buffers_size, + buffer->transaction ? "active" : "delivered"); +} + +/** + * binder_alloc_print_allocated() - print buffer info + * @m: seq_file for output via seq_printf() + * @alloc: binder_alloc for this proc + * + * Prints information about every buffer associated with + * the binder_alloc state to the given seq_file + */ +void binder_alloc_print_allocated(struct seq_file *m, + struct binder_alloc *alloc) +{ + struct rb_node *n; + + mutex_lock(&alloc->mutex); + for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n)) + print_binder_buffer(m, " buffer", + rb_entry(n, struct binder_buffer, rb_node)); + mutex_unlock(&alloc->mutex); +} + +/** + * binder_alloc_print_pages() - print page usage + * @m: seq_file for output via seq_printf() + * @alloc: binder_alloc for this proc + */ +void binder_alloc_print_pages(struct seq_file *m, + struct binder_alloc *alloc) +{ + struct binder_lru_page *page; + int i; + int active = 0; + int lru = 0; + int free = 0; + + mutex_lock(&alloc->mutex); + /* + * Make sure the binder_alloc is fully initialized, otherwise we might + * read inconsistent state. + */ + if (binder_alloc_get_vma(alloc) != NULL) { + for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) { + page = &alloc->pages[i]; + if (!page->page_ptr) + free++; + else if (list_empty(&page->lru)) + active++; + else + lru++; + } + } + mutex_unlock(&alloc->mutex); + seq_printf(m, " pages: %d:%d:%d\n", active, lru, free); + seq_printf(m, " pages high watermark: %zu\n", alloc->pages_high); +} + +/** + * binder_alloc_get_allocated_count() - return count of buffers + * @alloc: binder_alloc for this proc + * + * Return: count of allocated buffers + */ +int binder_alloc_get_allocated_count(struct binder_alloc *alloc) +{ + struct rb_node *n; + int count = 0; + + mutex_lock(&alloc->mutex); + for (n = rb_first(&alloc->allocated_buffers); n != NULL; n = rb_next(n)) + count++; + mutex_unlock(&alloc->mutex); + return count; +} + + +/** + * binder_alloc_vma_close() - invalidate address space + * @alloc: binder_alloc for this proc + * + * Called from binder_vma_close() when releasing address space. + * Clears alloc->vma to prevent new incoming transactions from + * allocating more buffers. + */ +void binder_alloc_vma_close(struct binder_alloc *alloc) +{ + binder_alloc_set_vma(alloc, NULL); +} + +/** + * binder_alloc_free_page() - shrinker callback to free pages + * @item: item to free + * @lock: lock protecting the item + * @cb_arg: callback argument + * + * Called from list_lru_walk() in binder_shrink_scan() to free + * up pages when the system is under memory pressure. + */ +enum lru_status binder_alloc_free_page(struct list_head *item, + struct list_lru_one *lru, + spinlock_t *lock, + void *cb_arg) + __must_hold(lock) +{ + struct mm_struct *mm = NULL; + struct binder_lru_page *page = container_of(item, + struct binder_lru_page, + lru); + struct binder_alloc *alloc; + uintptr_t page_addr; + size_t index; + struct vm_area_struct *vma; + + alloc = page->alloc; + if (!mutex_trylock(&alloc->mutex)) + goto err_get_alloc_mutex_failed; + + if (!page->page_ptr) + goto err_page_already_freed; + + index = page - alloc->pages; + page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE; + + mm = alloc->vma_vm_mm; + if (!mmget_not_zero(mm)) + goto err_mmget; + if (!mmap_read_trylock(mm)) + goto err_mmap_read_lock_failed; + vma = binder_alloc_get_vma(alloc); + + list_lru_isolate(lru, item); + spin_unlock(lock); + + if (vma) { + trace_binder_unmap_user_start(alloc, index); + + zap_page_range(vma, page_addr, PAGE_SIZE); + + trace_binder_unmap_user_end(alloc, index); + } + mmap_read_unlock(mm); + mmput_async(mm); + + trace_binder_unmap_kernel_start(alloc, index); + + __free_page(page->page_ptr); + page->page_ptr = NULL; + + trace_binder_unmap_kernel_end(alloc, index); + + spin_lock(lock); + mutex_unlock(&alloc->mutex); + return LRU_REMOVED_RETRY; + +err_mmap_read_lock_failed: + mmput_async(mm); +err_mmget: +err_page_already_freed: + mutex_unlock(&alloc->mutex); +err_get_alloc_mutex_failed: + return LRU_SKIP; +} + +static unsigned long +binder_shrink_count(struct shrinker *shrink, struct shrink_control *sc) +{ + unsigned long ret = list_lru_count(&binder_alloc_lru); + return ret; +} + +static unsigned long +binder_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) +{ + unsigned long ret; + + ret = list_lru_walk(&binder_alloc_lru, binder_alloc_free_page, + NULL, sc->nr_to_scan); + return ret; +} + +static struct shrinker binder_shrinker = { + .count_objects = binder_shrink_count, + .scan_objects = binder_shrink_scan, + .seeks = DEFAULT_SEEKS, +}; + +/** + * binder_alloc_init() - called by binder_open() for per-proc initialization + * @alloc: binder_alloc for this proc + * + * Called from binder_open() to initialize binder_alloc fields for + * new binder proc + */ +void binder_alloc_init(struct binder_alloc *alloc) +{ + alloc->pid = current->group_leader->pid; + mutex_init(&alloc->mutex); + INIT_LIST_HEAD(&alloc->buffers); +} + +int binder_alloc_shrinker_init(void) +{ + int ret = list_lru_init(&binder_alloc_lru); + + if (ret == 0) { + ret = register_shrinker(&binder_shrinker); + if (ret) + list_lru_destroy(&binder_alloc_lru); + } + return ret; +} + +void binder_alloc_shrinker_exit(void) +{ + unregister_shrinker(&binder_shrinker); + list_lru_destroy(&binder_alloc_lru); +} + +/** + * check_buffer() - verify that buffer/offset is safe to access + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @offset: offset into @buffer data + * @bytes: bytes to access from offset + * + * Check that the @offset/@bytes are within the size of the given + * @buffer and that the buffer is currently active and not freeable. + * Offsets must also be multiples of sizeof(u32). The kernel is + * allowed to touch the buffer in two cases: + * + * 1) when the buffer is being created: + * (buffer->free == 0 && buffer->allow_user_free == 0) + * 2) when the buffer is being torn down: + * (buffer->free == 0 && buffer->transaction == NULL). + * + * Return: true if the buffer is safe to access + */ +static inline bool check_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t offset, size_t bytes) +{ + size_t buffer_size = binder_alloc_buffer_size(alloc, buffer); + + return buffer_size >= bytes && + offset <= buffer_size - bytes && + IS_ALIGNED(offset, sizeof(u32)) && + !buffer->free && + (!buffer->allow_user_free || !buffer->transaction); +} + +/** + * binder_alloc_get_page() - get kernel pointer for given buffer offset + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @buffer_offset: offset into @buffer data + * @pgoffp: address to copy final page offset to + * + * Lookup the struct page corresponding to the address + * at @buffer_offset into @buffer->user_data. If @pgoffp is not + * NULL, the byte-offset into the page is written there. + * + * The caller is responsible to ensure that the offset points + * to a valid address within the @buffer and that @buffer is + * not freeable by the user. Since it can't be freed, we are + * guaranteed that the corresponding elements of @alloc->pages[] + * cannot change. + * + * Return: struct page + */ +static struct page *binder_alloc_get_page(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + pgoff_t *pgoffp) +{ + binder_size_t buffer_space_offset = buffer_offset + + (buffer->user_data - alloc->buffer); + pgoff_t pgoff = buffer_space_offset & ~PAGE_MASK; + size_t index = buffer_space_offset >> PAGE_SHIFT; + struct binder_lru_page *lru_page; + + lru_page = &alloc->pages[index]; + *pgoffp = pgoff; + return lru_page->page_ptr; +} + +/** + * binder_alloc_clear_buf() - zero out buffer + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be cleared + * + * memset the given buffer to 0 + */ +static void binder_alloc_clear_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer) +{ + size_t bytes = binder_alloc_buffer_size(alloc, buffer); + binder_size_t buffer_offset = 0; + + while (bytes) { + unsigned long size; + struct page *page; + pgoff_t pgoff; + void *kptr; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + kptr = kmap(page) + pgoff; + memset(kptr, 0, size); + kunmap(page); + bytes -= size; + buffer_offset += size; + } +} + +/** + * binder_alloc_copy_user_to_buffer() - copy src user to tgt user + * @alloc: binder_alloc for this proc + * @buffer: binder buffer to be accessed + * @buffer_offset: offset into @buffer data + * @from: userspace pointer to source buffer + * @bytes: bytes to copy + * + * Copy bytes from source userspace to target buffer. + * + * Return: bytes remaining to be copied + */ +unsigned long +binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + const void __user *from, + size_t bytes) +{ + if (!check_buffer(alloc, buffer, buffer_offset, bytes)) + return bytes; + + while (bytes) { + unsigned long size; + unsigned long ret; + struct page *page; + pgoff_t pgoff; + void *kptr; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + kptr = kmap(page) + pgoff; + ret = copy_from_user(kptr, from, size); + kunmap(page); + if (ret) + return bytes - size + ret; + bytes -= size; + from += size; + buffer_offset += size; + } + return 0; +} + +static int binder_alloc_do_buffer_copy(struct binder_alloc *alloc, + bool to_buffer, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *ptr, + size_t bytes) +{ + /* All copies must be 32-bit aligned and 32-bit size */ + if (!check_buffer(alloc, buffer, buffer_offset, bytes)) + return -EINVAL; + + while (bytes) { + unsigned long size; + struct page *page; + pgoff_t pgoff; + void *tmpptr; + void *base_ptr; + + page = binder_alloc_get_page(alloc, buffer, + buffer_offset, &pgoff); + size = min_t(size_t, bytes, PAGE_SIZE - pgoff); + base_ptr = kmap_atomic(page); + tmpptr = base_ptr + pgoff; + if (to_buffer) + memcpy(tmpptr, ptr, size); + else + memcpy(ptr, tmpptr, size); + /* + * kunmap_atomic() takes care of flushing the cache + * if this device has VIVT cache arch + */ + kunmap_atomic(base_ptr); + bytes -= size; + pgoff = 0; + ptr = ptr + size; + buffer_offset += size; + } + return 0; +} + +int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *src, + size_t bytes) +{ + return binder_alloc_do_buffer_copy(alloc, true, buffer, buffer_offset, + src, bytes); +} + +int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, + void *dest, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + size_t bytes) +{ + return binder_alloc_do_buffer_copy(alloc, false, buffer, buffer_offset, + dest, bytes); +} + diff --git a/binder/binder_alloc.h b/binder/binder_alloc.h new file mode 100644 index 0000000..f6052c9 --- /dev/null +++ b/binder/binder_alloc.h @@ -0,0 +1,181 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2017 Google, Inc. + */ + +#ifndef _LINUX_BINDER_ALLOC_H +#define _LINUX_BINDER_ALLOC_H + +#include +#include +#include +#include +#include +#include +#include +#include + +extern struct list_lru binder_alloc_lru; +struct binder_transaction; + +/** + * struct binder_buffer - buffer used for binder transactions + * @entry: entry alloc->buffers + * @rb_node: node for allocated_buffers/free_buffers rb trees + * @free: %true if buffer is free + * @clear_on_free: %true if buffer must be zeroed after use + * @allow_user_free: %true if user is allowed to free buffer + * @async_transaction: %true if buffer is in use for an async txn + * @debug_id: unique ID for debugging + * @transaction: pointer to associated struct binder_transaction + * @target_node: struct binder_node associated with this buffer + * @data_size: size of @transaction data + * @offsets_size: size of array of offsets + * @extra_buffers_size: size of space for other objects (like sg lists) + * @user_data: user pointer to base of buffer space + * @pid: pid to attribute the buffer to (caller) + * + * Bookkeeping structure for binder transaction buffers + */ +struct binder_buffer { + struct list_head entry; /* free and allocated entries by address */ + struct rb_node rb_node; /* free entry by size or allocated entry */ + /* by address */ + unsigned free:1; + unsigned clear_on_free:1; + unsigned allow_user_free:1; + unsigned async_transaction:1; + unsigned debug_id:28; + + struct binder_transaction *transaction; + + struct binder_node *target_node; + size_t data_size; + size_t offsets_size; + size_t extra_buffers_size; + void __user *user_data; + int pid; +}; + +/** + * struct binder_lru_page - page object used for binder shrinker + * @page_ptr: pointer to physical page in mmap'd space + * @lru: entry in binder_alloc_lru + * @alloc: binder_alloc for a proc + */ +struct binder_lru_page { + struct list_head lru; + struct page *page_ptr; + struct binder_alloc *alloc; +}; + +/** + * struct binder_alloc - per-binder proc state for binder allocator + * @vma: vm_area_struct passed to mmap_handler + * (invarient after mmap) + * @tsk: tid for task that called init for this proc + * (invariant after init) + * @vma_vm_mm: copy of vma->vm_mm (invarient after mmap) + * @buffer: base of per-proc address space mapped via mmap + * @buffers: list of all buffers for this proc + * @free_buffers: rb tree of buffers available for allocation + * sorted by size + * @allocated_buffers: rb tree of allocated buffers sorted by address + * @free_async_space: VA space available for async buffers. This is + * initialized at mmap time to 1/2 the full VA space + * @pages: array of binder_lru_page + * @buffer_size: size of address space specified via mmap + * @pid: pid for associated binder_proc (invariant after init) + * @pages_high: high watermark of offset in @pages + * + * Bookkeeping structure for per-proc address space management for binder + * buffers. It is normally initialized during binder_init() and binder_mmap() + * calls. The address space is used for both user-visible buffers and for + * struct binder_buffer objects used to track the user buffers + */ +struct binder_alloc { + struct mutex mutex; + struct vm_area_struct *vma; + struct mm_struct *vma_vm_mm; + void __user *buffer; + struct list_head buffers; + struct rb_root free_buffers; + struct rb_root allocated_buffers; + size_t free_async_space; + struct binder_lru_page *pages; + size_t buffer_size; + uint32_t buffer_free; + int pid; + size_t pages_high; +}; + +#ifdef CONFIG_ANDROID_BINDER_IPC_SELFTEST +void binder_selftest_alloc(struct binder_alloc *alloc); +#else +static inline void binder_selftest_alloc(struct binder_alloc *alloc) {} +#endif +enum lru_status binder_alloc_free_page(struct list_head *item, + struct list_lru_one *lru, + spinlock_t *lock, void *cb_arg); +extern struct binder_buffer *binder_alloc_new_buf(struct binder_alloc *alloc, + size_t data_size, + size_t offsets_size, + size_t extra_buffers_size, + int is_async, + int pid); +extern void binder_alloc_init(struct binder_alloc *alloc); +extern int binder_alloc_shrinker_init(void); +extern void binder_alloc_shrinker_exit(void); +extern void binder_alloc_vma_close(struct binder_alloc *alloc); +extern struct binder_buffer * +binder_alloc_prepare_to_free(struct binder_alloc *alloc, + uintptr_t user_ptr); +extern void binder_alloc_free_buf(struct binder_alloc *alloc, + struct binder_buffer *buffer); +extern int binder_alloc_mmap_handler(struct binder_alloc *alloc, + struct vm_area_struct *vma); +extern void binder_alloc_deferred_release(struct binder_alloc *alloc); +extern int binder_alloc_get_allocated_count(struct binder_alloc *alloc); +extern void binder_alloc_print_allocated(struct seq_file *m, + struct binder_alloc *alloc); +void binder_alloc_print_pages(struct seq_file *m, + struct binder_alloc *alloc); + +/** + * binder_alloc_get_free_async_space() - get free space available for async + * @alloc: binder_alloc for this proc + * + * Return: the bytes remaining in the address-space for async transactions + */ +static inline size_t +binder_alloc_get_free_async_space(struct binder_alloc *alloc) +{ + size_t free_async_space; + + mutex_lock(&alloc->mutex); + free_async_space = alloc->free_async_space; + mutex_unlock(&alloc->mutex); + return free_async_space; +} + +unsigned long +binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + const void __user *from, + size_t bytes); + +int binder_alloc_copy_to_buffer(struct binder_alloc *alloc, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + void *src, + size_t bytes); + +int binder_alloc_copy_from_buffer(struct binder_alloc *alloc, + void *dest, + struct binder_buffer *buffer, + binder_size_t buffer_offset, + size_t bytes); + +#endif /* _LINUX_BINDER_ALLOC_H */ + diff --git a/binder/binder_internal.h b/binder/binder_internal.h new file mode 100644 index 0000000..e439a18 --- /dev/null +++ b/binder/binder_internal.h @@ -0,0 +1,150 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_BINDER_INTERNAL_H +#define _LINUX_BINDER_INTERNAL_H + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct binder_context { + struct binder_node *binder_context_mgr_node; + struct mutex context_mgr_node_lock; + kuid_t binder_context_mgr_uid; + const char *name; +}; + +/** + * struct binder_device - information about a binder device node + * @hlist: list of binder devices (only used for devices requested via + * CONFIG_ANDROID_BINDER_DEVICES) + * @miscdev: information about a binder character device node + * @context: binder context information + * @binderfs_inode: This is the inode of the root dentry of the super block + * belonging to a binderfs mount. + */ +struct binder_device { + struct hlist_node hlist; + struct miscdevice miscdev; + struct binder_context context; + struct inode *binderfs_inode; + refcount_t ref; +}; + +/** + * binderfs_mount_opts - mount options for binderfs + * @max: maximum number of allocatable binderfs binder devices + * @stats_mode: enable binder stats in binderfs. + */ +struct binderfs_mount_opts { + int max; + int stats_mode; +}; + +/** + * binderfs_info - information about a binderfs mount + * @ipc_ns: The ipc namespace the binderfs mount belongs to. + * @control_dentry: This records the dentry of this binderfs mount + * binder-control device. + * @root_uid: uid that needs to be used when a new binder device is + * created. + * @root_gid: gid that needs to be used when a new binder device is + * created. + * @mount_opts: The mount options in use. + * @device_count: The current number of allocated binder devices. + * @proc_log_dir: Pointer to the directory dentry containing process-specific + * logs. + */ +struct binderfs_info { + struct ipc_namespace *ipc_ns; + struct dentry *control_dentry; + kuid_t root_uid; + kgid_t root_gid; + struct binderfs_mount_opts mount_opts; + int device_count; + struct dentry *proc_log_dir; +}; + +extern const struct file_operations binder_fops; + +extern char *binder_devices_param; + +#ifdef CONFIG_ANDROID_BINDERFS +extern bool is_binderfs_device(const struct inode *inode); +extern struct dentry *binderfs_create_file(struct dentry *dir, const char *name, + const struct file_operations *fops, + void *data); +extern void binderfs_remove_file(struct dentry *dentry); +#else +static inline bool is_binderfs_device(const struct inode *inode) +{ + return false; +} +static inline struct dentry *binderfs_create_file(struct dentry *dir, + const char *name, + const struct file_operations *fops, + void *data) +{ + return NULL; +} +static inline void binderfs_remove_file(struct dentry *dentry) {} +#endif + +#ifdef CONFIG_ANDROID_BINDERFS +extern int __init init_binderfs(void); +extern void __exit exit_binderfs(void); +#else +static inline int __init init_binderfs(void) +{ + return 0; +} +static inline void __exit exit_binderfs(void) +{ +} +#endif + +int binder_stats_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(binder_stats); + +int binder_state_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(binder_state); + +int binder_transactions_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(binder_transactions); + +int binder_transaction_log_show(struct seq_file *m, void *unused); +DEFINE_SHOW_ATTRIBUTE(binder_transaction_log); + +struct binder_transaction_log_entry { + int debug_id; + int debug_id_done; + int call_type; + int from_proc; + int from_thread; + int target_handle; + int to_proc; + int to_thread; + int to_node; + int data_size; + int offsets_size; + int return_error_line; + uint32_t return_error; + uint32_t return_error_param; + char context_name[BINDERFS_MAX_NAME + 1]; +}; + +struct binder_transaction_log { + atomic_t cur; + bool full; + struct binder_transaction_log_entry entry[32]; +}; + +extern struct binder_transaction_log binder_transaction_log; +extern struct binder_transaction_log binder_transaction_log_failed; +#endif /* _LINUX_BINDER_INTERNAL_H */ diff --git a/binder/binder_trace.h b/binder/binder_trace.h index 7f20f3d..6731c3c 100644 --- a/binder/binder_trace.h +++ b/binder/binder_trace.h @@ -1,15 +1,6 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ /* * Copyright (C) 2012 Google, Inc. - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * */ #undef TRACE_SYSTEM @@ -23,7 +14,8 @@ struct binder_buffer; struct binder_node; struct binder_proc; -struct binder_ref; +struct binder_alloc; +struct binder_ref_data; struct binder_thread; struct binder_transaction; @@ -146,8 +138,8 @@ TRACE_EVENT(binder_transaction_received, TRACE_EVENT(binder_transaction_node_to_ref, TP_PROTO(struct binder_transaction *t, struct binder_node *node, - struct binder_ref *ref), - TP_ARGS(t, node, ref), + struct binder_ref_data *rdata), + TP_ARGS(t, node, rdata), TP_STRUCT__entry( __field(int, debug_id) @@ -160,8 +152,8 @@ TRACE_EVENT(binder_transaction_node_to_ref, __entry->debug_id = t->debug_id; __entry->node_debug_id = node->debug_id; __entry->node_ptr = node->ptr; - __entry->ref_debug_id = ref->debug_id; - __entry->ref_desc = ref->desc; + __entry->ref_debug_id = rdata->debug_id; + __entry->ref_desc = rdata->desc; ), TP_printk("transaction=%d node=%d src_ptr=0x%016llx ==> dest_ref=%d dest_desc=%d", __entry->debug_id, __entry->node_debug_id, @@ -170,8 +162,9 @@ TRACE_EVENT(binder_transaction_node_to_ref, ); TRACE_EVENT(binder_transaction_ref_to_node, - TP_PROTO(struct binder_transaction *t, struct binder_ref *ref), - TP_ARGS(t, ref), + TP_PROTO(struct binder_transaction *t, struct binder_node *node, + struct binder_ref_data *rdata), + TP_ARGS(t, node, rdata), TP_STRUCT__entry( __field(int, debug_id) @@ -182,10 +175,10 @@ TRACE_EVENT(binder_transaction_ref_to_node, ), TP_fast_assign( __entry->debug_id = t->debug_id; - __entry->ref_debug_id = ref->debug_id; - __entry->ref_desc = ref->desc; - __entry->node_debug_id = ref->node->debug_id; - __entry->node_ptr = ref->node->ptr; + __entry->ref_debug_id = rdata->debug_id; + __entry->ref_desc = rdata->desc; + __entry->node_debug_id = node->debug_id; + __entry->node_ptr = node->ptr; ), TP_printk("transaction=%d node=%d src_ref=%d src_desc=%d ==> dest_ptr=0x%016llx", __entry->debug_id, __entry->node_debug_id, @@ -194,9 +187,10 @@ TRACE_EVENT(binder_transaction_ref_to_node, ); TRACE_EVENT(binder_transaction_ref_to_ref, - TP_PROTO(struct binder_transaction *t, struct binder_ref *src_ref, - struct binder_ref *dest_ref), - TP_ARGS(t, src_ref, dest_ref), + TP_PROTO(struct binder_transaction *t, struct binder_node *node, + struct binder_ref_data *src_ref, + struct binder_ref_data *dest_ref), + TP_ARGS(t, node, src_ref, dest_ref), TP_STRUCT__entry( __field(int, debug_id) @@ -208,7 +202,7 @@ TRACE_EVENT(binder_transaction_ref_to_ref, ), TP_fast_assign( __entry->debug_id = t->debug_id; - __entry->node_debug_id = src_ref->node->debug_id; + __entry->node_debug_id = node->debug_id; __entry->src_ref_debug_id = src_ref->debug_id; __entry->src_ref_desc = src_ref->desc; __entry->dest_ref_debug_id = dest_ref->debug_id; @@ -220,22 +214,40 @@ TRACE_EVENT(binder_transaction_ref_to_ref, __entry->dest_ref_debug_id, __entry->dest_ref_desc) ); -TRACE_EVENT(binder_transaction_fd, - TP_PROTO(struct binder_transaction *t, int src_fd, int dest_fd), - TP_ARGS(t, src_fd, dest_fd), +TRACE_EVENT(binder_transaction_fd_send, + TP_PROTO(struct binder_transaction *t, int fd, size_t offset), + TP_ARGS(t, fd, offset), TP_STRUCT__entry( __field(int, debug_id) - __field(int, src_fd) - __field(int, dest_fd) + __field(int, fd) + __field(size_t, offset) ), TP_fast_assign( __entry->debug_id = t->debug_id; - __entry->src_fd = src_fd; - __entry->dest_fd = dest_fd; + __entry->fd = fd; + __entry->offset = offset; ), - TP_printk("transaction=%d src_fd=%d ==> dest_fd=%d", - __entry->debug_id, __entry->src_fd, __entry->dest_fd) + TP_printk("transaction=%d src_fd=%d offset=%zu", + __entry->debug_id, __entry->fd, __entry->offset) +); + +TRACE_EVENT(binder_transaction_fd_recv, + TP_PROTO(struct binder_transaction *t, int fd, size_t offset), + TP_ARGS(t, fd, offset), + + TP_STRUCT__entry( + __field(int, debug_id) + __field(int, fd) + __field(size_t, offset) + ), + TP_fast_assign( + __entry->debug_id = t->debug_id; + __entry->fd = fd; + __entry->offset = offset; + ), + TP_printk("transaction=%d dest_fd=%d offset=%zu", + __entry->debug_id, __entry->fd, __entry->offset) ); DECLARE_EVENT_CLASS(binder_buffer_class, @@ -245,14 +257,17 @@ DECLARE_EVENT_CLASS(binder_buffer_class, __field(int, debug_id) __field(size_t, data_size) __field(size_t, offsets_size) + __field(size_t, extra_buffers_size) ), TP_fast_assign( __entry->debug_id = buf->debug_id; __entry->data_size = buf->data_size; __entry->offsets_size = buf->offsets_size; + __entry->extra_buffers_size = buf->extra_buffers_size; ), - TP_printk("transaction=%d data_size=%zd offsets_size=%zd", - __entry->debug_id, __entry->data_size, __entry->offsets_size) + TP_printk("transaction=%d data_size=%zd offsets_size=%zd extra_buffers_size=%zd", + __entry->debug_id, __entry->data_size, __entry->offsets_size, + __entry->extra_buffers_size) ); DEFINE_EVENT(binder_buffer_class, binder_transaction_alloc_buf, @@ -268,9 +283,9 @@ DEFINE_EVENT(binder_buffer_class, binder_transaction_failed_buffer_release, TP_ARGS(buffer)); TRACE_EVENT(binder_update_page_range, - TP_PROTO(struct binder_proc *proc, bool allocate, - void *start, void *end), - TP_ARGS(proc, allocate, start, end), + TP_PROTO(struct binder_alloc *alloc, bool allocate, + void __user *start, void __user *end), + TP_ARGS(alloc, allocate, start, end), TP_STRUCT__entry( __field(int, proc) __field(bool, allocate) @@ -278,9 +293,9 @@ TRACE_EVENT(binder_update_page_range, __field(size_t, size) ), TP_fast_assign( - __entry->proc = proc->pid; + __entry->proc = alloc->pid; __entry->allocate = allocate; - __entry->offset = start - proc->buffer; + __entry->offset = start - alloc->buffer; __entry->size = end - start; ), TP_printk("proc=%d allocate=%d offset=%zu size=%zu", @@ -288,6 +303,61 @@ TRACE_EVENT(binder_update_page_range, __entry->offset, __entry->size) ); +DECLARE_EVENT_CLASS(binder_lru_page_class, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index), + TP_STRUCT__entry( + __field(int, proc) + __field(size_t, page_index) + ), + TP_fast_assign( + __entry->proc = alloc->pid; + __entry->page_index = page_index; + ), + TP_printk("proc=%d page_index=%zu", + __entry->proc, __entry->page_index) +); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_lru_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_lru_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_free_lru_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_free_lru_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_page_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_alloc_page_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_user_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_user_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_kernel_start, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + +DEFINE_EVENT(binder_lru_page_class, binder_unmap_kernel_end, + TP_PROTO(const struct binder_alloc *alloc, size_t page_index), + TP_ARGS(alloc, page_index)); + TRACE_EVENT(binder_command, TP_PROTO(uint32_t cmd), TP_ARGS(cmd), diff --git a/binder/binderfs.c b/binder/binderfs.c new file mode 100644 index 0000000..8119f0d --- /dev/null +++ b/binder/binderfs.c @@ -0,0 +1,812 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "binder_internal.h" +#include "deps.h" + +#define FIRST_INODE 1 +#define SECOND_INODE 2 +#define INODE_OFFSET 3 +#define INTSTRLEN 21 +#define BINDERFS_MAX_MINOR (1U << MINORBITS) +/* Ensure that the initial ipc namespace always has devices available. */ +#define BINDERFS_MAX_MINOR_CAPPED (BINDERFS_MAX_MINOR - 4) + +static dev_t binderfs_dev; +static DEFINE_MUTEX(binderfs_minors_mutex); +static DEFINE_IDA(binderfs_minors); + +enum binderfs_param { + Opt_max, + Opt_stats_mode, +}; + +enum binderfs_stats_mode { + binderfs_stats_mode_unset, + binderfs_stats_mode_global, +}; + +static const struct constant_table binderfs_param_stats[] = { + { "global", binderfs_stats_mode_global }, + {} +}; + +static const struct fs_parameter_spec binderfs_fs_parameters[] = { + fsparam_u32("max", Opt_max), + fsparam_enum("stats", Opt_stats_mode, binderfs_param_stats), + {} +}; + +static inline struct binderfs_info *BINDERFS_SB(const struct super_block *sb) +{ + return sb->s_fs_info; +} + +bool is_binderfs_device(const struct inode *inode) +{ + if (inode->i_sb->s_magic == BINDERFS_SUPER_MAGIC) + return true; + + return false; +} + +/** + * binderfs_binder_device_create - allocate inode from super block of a + * binderfs mount + * @ref_inode: inode from wich the super block will be taken + * @userp: buffer to copy information about new device for userspace to + * @req: struct binderfs_device as copied from userspace + * + * This function allocates a new binder_device and reserves a new minor + * number for it. + * Minor numbers are limited and tracked globally in binderfs_minors. The + * function will stash a struct binder_device for the specific binder + * device in i_private of the inode. + * It will go on to allocate a new inode from the super block of the + * filesystem mount, stash a struct binder_device in its i_private field + * and attach a dentry to that inode. + * + * Return: 0 on success, negative errno on failure + */ +static int binderfs_binder_device_create(struct inode *ref_inode, + struct binderfs_device __user *userp, + struct binderfs_device *req) +{ + int minor, ret; + struct dentry *dentry, *root; + struct binder_device *device; + char *name = NULL; + size_t name_len; + struct inode *inode = NULL; + struct super_block *sb = ref_inode->i_sb; + struct binderfs_info *info = sb->s_fs_info; +#if defined(CONFIG_IPC_NS) + bool use_reserve = (info->ipc_ns == get_init_ipc_ns_ptr()); +#else + bool use_reserve = true; +#endif + + /* Reserve new minor number for the new device. */ + mutex_lock(&binderfs_minors_mutex); + if (++info->device_count <= info->mount_opts.max) + minor = ida_alloc_max(&binderfs_minors, + use_reserve ? BINDERFS_MAX_MINOR : + BINDERFS_MAX_MINOR_CAPPED, + GFP_KERNEL); + else + minor = -ENOSPC; + if (minor < 0) { + --info->device_count; + mutex_unlock(&binderfs_minors_mutex); + return minor; + } + mutex_unlock(&binderfs_minors_mutex); + + ret = -ENOMEM; + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + goto err; + + inode = new_inode(sb); + if (!inode) + goto err; + + inode->i_ino = minor + INODE_OFFSET; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + init_special_inode(inode, S_IFCHR | 0600, + MKDEV(MAJOR(binderfs_dev), minor)); + inode->i_fop = &binder_fops; + inode->i_uid = info->root_uid; + inode->i_gid = info->root_gid; + + req->name[BINDERFS_MAX_NAME] = '\0'; /* NUL-terminate */ + name_len = strlen(req->name); + /* Make sure to include terminating NUL byte */ + name = kmemdup(req->name, name_len + 1, GFP_KERNEL); + if (!name) + goto err; + + refcount_set(&device->ref, 1); + device->binderfs_inode = inode; + device->context.binder_context_mgr_uid = INVALID_UID; + device->context.name = name; + device->miscdev.name = name; + device->miscdev.minor = minor; + mutex_init(&device->context.context_mgr_node_lock); + + req->major = MAJOR(binderfs_dev); + req->minor = minor; + + if (userp && copy_to_user(userp, req, sizeof(*req))) { + ret = -EFAULT; + goto err; + } + + root = sb->s_root; + inode_lock(d_inode(root)); + + /* look it up */ + dentry = lookup_one_len(name, root, name_len); + if (IS_ERR(dentry)) { + inode_unlock(d_inode(root)); + ret = PTR_ERR(dentry); + goto err; + } + + if (d_really_is_positive(dentry)) { + /* already exists */ + dput(dentry); + inode_unlock(d_inode(root)); + ret = -EEXIST; + goto err; + } + + inode->i_private = device; + d_instantiate(dentry, inode); + fsnotify_create(root->d_inode, dentry); + inode_unlock(d_inode(root)); + + return 0; + +err: + kfree(name); + kfree(device); + mutex_lock(&binderfs_minors_mutex); + --info->device_count; + ida_free(&binderfs_minors, minor); + mutex_unlock(&binderfs_minors_mutex); + iput(inode); + + return ret; +} + +/** + * binderfs_ctl_ioctl - handle binder device node allocation requests + * + * The request handler for the binder-control device. All requests operate on + * the binderfs mount the binder-control device resides in: + * - BINDER_CTL_ADD + * Allocate a new binder device. + * + * Return: 0 on success, negative errno on failure + */ +static long binder_ctl_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int ret = -EINVAL; + struct inode *inode = file_inode(file); + struct binderfs_device __user *device = (struct binderfs_device __user *)arg; + struct binderfs_device device_req; + + switch (cmd) { + case BINDER_CTL_ADD: + ret = copy_from_user(&device_req, device, sizeof(device_req)); + if (ret) { + ret = -EFAULT; + break; + } + + ret = binderfs_binder_device_create(inode, device, &device_req); + break; + default: + break; + } + + return ret; +} + +static void binderfs_evict_inode(struct inode *inode) +{ + struct binder_device *device = inode->i_private; + struct binderfs_info *info = BINDERFS_SB(inode->i_sb); + + clear_inode(inode); + + if (!S_ISCHR(inode->i_mode) || !device) + return; + + mutex_lock(&binderfs_minors_mutex); + --info->device_count; + ida_free(&binderfs_minors, device->miscdev.minor); + mutex_unlock(&binderfs_minors_mutex); + + if (refcount_dec_and_test(&device->ref)) { + kfree(device->context.name); + kfree(device); + } +} + +static int binderfs_fs_context_parse_param(struct fs_context *fc, + struct fs_parameter *param) +{ + int opt; + struct binderfs_mount_opts *ctx = fc->fs_private; + struct fs_parse_result result; + + opt = fs_parse(fc, binderfs_fs_parameters, param, &result); + if (opt < 0) + return opt; + + switch (opt) { + case Opt_max: + if (result.uint_32 > BINDERFS_MAX_MINOR) + return invalfc(fc, "Bad value for '%s'", param->key); + + ctx->max = result.uint_32; + break; + case Opt_stats_mode: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + ctx->stats_mode = result.uint_32; + break; + default: + return invalfc(fc, "Unsupported parameter '%s'", param->key); + } + + return 0; +} + +static int binderfs_fs_context_reconfigure(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx = fc->fs_private; + struct binderfs_info *info = BINDERFS_SB(fc->root->d_sb); + + if (info->mount_opts.stats_mode != ctx->stats_mode) + return invalfc(fc, "Binderfs stats mode cannot be changed during a remount"); + + info->mount_opts.stats_mode = ctx->stats_mode; + info->mount_opts.max = ctx->max; + return 0; +} + +static int binderfs_show_options(struct seq_file *seq, struct dentry *root) +{ + struct binderfs_info *info = BINDERFS_SB(root->d_sb); + + if (info->mount_opts.max <= BINDERFS_MAX_MINOR) + seq_printf(seq, ",max=%d", info->mount_opts.max); + + switch (info->mount_opts.stats_mode) { + case binderfs_stats_mode_unset: + break; + case binderfs_stats_mode_global: + seq_printf(seq, ",stats=global"); + break; + } + + return 0; +} + +static void binderfs_put_super(struct super_block *sb) +{ + struct binderfs_info *info = sb->s_fs_info; + + if (info && info->ipc_ns) + put_ipc_ns(info->ipc_ns); + + kfree(info); + sb->s_fs_info = NULL; +} + +static const struct super_operations binderfs_super_ops = { + .evict_inode = binderfs_evict_inode, + .show_options = binderfs_show_options, + .statfs = simple_statfs, + .put_super = binderfs_put_super, +}; + +static inline bool is_binderfs_control_device(const struct dentry *dentry) +{ + struct binderfs_info *info = dentry->d_sb->s_fs_info; + + return info->control_dentry == dentry; +} + +static int binderfs_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry, + unsigned int flags) +{ + if (is_binderfs_control_device(old_dentry) || + is_binderfs_control_device(new_dentry)) + return -EPERM; + + return simple_rename(old_dir, old_dentry, new_dir, new_dentry, flags); +} + +static int binderfs_unlink(struct inode *dir, struct dentry *dentry) +{ + if (is_binderfs_control_device(dentry)) + return -EPERM; + + return simple_unlink(dir, dentry); +} + +static const struct file_operations binder_ctl_fops = { + .owner = THIS_MODULE, + .open = nonseekable_open, + .unlocked_ioctl = binder_ctl_ioctl, + .compat_ioctl = binder_ctl_ioctl, + .llseek = noop_llseek, +}; + +/** + * binderfs_binder_ctl_create - create a new binder-control device + * @sb: super block of the binderfs mount + * + * This function creates a new binder-control device node in the binderfs mount + * referred to by @sb. + * + * Return: 0 on success, negative errno on failure + */ +static int binderfs_binder_ctl_create(struct super_block *sb) +{ + int minor, ret; + struct dentry *dentry; + struct binder_device *device; + struct inode *inode = NULL; + struct dentry *root = sb->s_root; + struct binderfs_info *info = sb->s_fs_info; +#if defined(CONFIG_IPC_NS) + bool use_reserve = (info->ipc_ns == get_init_ipc_ns_ptr()); +#else + bool use_reserve = true; +#endif + + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + return -ENOMEM; + + /* If we have already created a binder-control node, return. */ + if (info->control_dentry) { + ret = 0; + goto out; + } + + ret = -ENOMEM; + inode = new_inode(sb); + if (!inode) + goto out; + + /* Reserve a new minor number for the new device. */ + mutex_lock(&binderfs_minors_mutex); + minor = ida_alloc_max(&binderfs_minors, + use_reserve ? BINDERFS_MAX_MINOR : + BINDERFS_MAX_MINOR_CAPPED, + GFP_KERNEL); + mutex_unlock(&binderfs_minors_mutex); + if (minor < 0) { + ret = minor; + goto out; + } + + inode->i_ino = SECOND_INODE; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + init_special_inode(inode, S_IFCHR | 0600, + MKDEV(MAJOR(binderfs_dev), minor)); + inode->i_fop = &binder_ctl_fops; + inode->i_uid = info->root_uid; + inode->i_gid = info->root_gid; + + refcount_set(&device->ref, 1); + device->binderfs_inode = inode; + device->miscdev.minor = minor; + + dentry = d_alloc_name(root, "binder-control"); + if (!dentry) + goto out; + + inode->i_private = device; + info->control_dentry = dentry; + d_add(dentry, inode); + + return 0; + +out: + kfree(device); + iput(inode); + + return ret; +} + +static const struct inode_operations binderfs_dir_inode_operations = { + .lookup = simple_lookup, + .rename = binderfs_rename, + .unlink = binderfs_unlink, +}; + +static struct inode *binderfs_make_inode(struct super_block *sb, int mode) +{ + struct inode *ret; + + ret = new_inode(sb); + if (ret) { + ret->i_ino = iunique(sb, BINDERFS_MAX_MINOR + INODE_OFFSET); + ret->i_mode = mode; + ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret); + } + return ret; +} + +static struct dentry *binderfs_create_dentry(struct dentry *parent, + const char *name) +{ + struct dentry *dentry; + + dentry = lookup_one_len(name, parent, strlen(name)); + if (IS_ERR(dentry)) + return dentry; + + /* Return error if the file/dir already exists. */ + if (d_really_is_positive(dentry)) { + dput(dentry); + return ERR_PTR(-EEXIST); + } + + return dentry; +} + +void binderfs_remove_file(struct dentry *dentry) +{ + struct inode *parent_inode; + + parent_inode = d_inode(dentry->d_parent); + inode_lock(parent_inode); + if (simple_positive(dentry)) { + dget(dentry); + simple_unlink(parent_inode, dentry); + d_delete(dentry); + dput(dentry); + } + inode_unlock(parent_inode); +} + +struct dentry *binderfs_create_file(struct dentry *parent, const char *name, + const struct file_operations *fops, + void *data) +{ + struct dentry *dentry; + struct inode *new_inode, *parent_inode; + struct super_block *sb; + + parent_inode = d_inode(parent); + inode_lock(parent_inode); + + dentry = binderfs_create_dentry(parent, name); + if (IS_ERR(dentry)) + goto out; + + sb = parent_inode->i_sb; + new_inode = binderfs_make_inode(sb, S_IFREG | 0444); + if (!new_inode) { + dput(dentry); + dentry = ERR_PTR(-ENOMEM); + goto out; + } + + new_inode->i_fop = fops; + new_inode->i_private = data; + d_instantiate(dentry, new_inode); + fsnotify_create(parent_inode, dentry); + +out: + inode_unlock(parent_inode); + return dentry; +} + +static struct dentry *binderfs_create_dir(struct dentry *parent, + const char *name) +{ + struct dentry *dentry; + struct inode *new_inode, *parent_inode; + struct super_block *sb; + + parent_inode = d_inode(parent); + inode_lock(parent_inode); + + dentry = binderfs_create_dentry(parent, name); + if (IS_ERR(dentry)) + goto out; + + sb = parent_inode->i_sb; + new_inode = binderfs_make_inode(sb, S_IFDIR | 0755); + if (!new_inode) { + dput(dentry); + dentry = ERR_PTR(-ENOMEM); + goto out; + } + + new_inode->i_fop = &simple_dir_operations; + new_inode->i_op = &simple_dir_inode_operations; + + set_nlink(new_inode, 2); + d_instantiate(dentry, new_inode); + inc_nlink(parent_inode); + fsnotify_mkdir(parent_inode, dentry); + +out: + inode_unlock(parent_inode); + return dentry; +} + +static int init_binder_logs(struct super_block *sb) +{ + struct dentry *binder_logs_root_dir, *dentry, *proc_log_dir; + struct binderfs_info *info; + int ret = 0; + + binder_logs_root_dir = binderfs_create_dir(sb->s_root, + "binder_logs"); + if (IS_ERR(binder_logs_root_dir)) { + ret = PTR_ERR(binder_logs_root_dir); + goto out; + } + + dentry = binderfs_create_file(binder_logs_root_dir, "stats", + &binder_stats_fops, NULL); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + + dentry = binderfs_create_file(binder_logs_root_dir, "state", + &binder_state_fops, NULL); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + + dentry = binderfs_create_file(binder_logs_root_dir, "transactions", + &binder_transactions_fops, NULL); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + + dentry = binderfs_create_file(binder_logs_root_dir, + "transaction_log", + &binder_transaction_log_fops, + &binder_transaction_log); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + + dentry = binderfs_create_file(binder_logs_root_dir, + "failed_transaction_log", + &binder_transaction_log_fops, + &binder_transaction_log_failed); + if (IS_ERR(dentry)) { + ret = PTR_ERR(dentry); + goto out; + } + + proc_log_dir = binderfs_create_dir(binder_logs_root_dir, "proc"); + if (IS_ERR(proc_log_dir)) { + ret = PTR_ERR(proc_log_dir); + goto out; + } + info = sb->s_fs_info; + info->proc_log_dir = proc_log_dir; + +out: + return ret; +} + +static int binderfs_fill_super(struct super_block *sb, struct fs_context *fc) +{ + int ret; + struct binderfs_info *info; + struct binderfs_mount_opts *ctx = fc->fs_private; + struct inode *inode = NULL; + struct binderfs_device device_info = {}; + const char *name; + size_t len; + + sb->s_blocksize = PAGE_SIZE; + sb->s_blocksize_bits = PAGE_SHIFT; + + /* + * The binderfs filesystem can be mounted by userns root in a + * non-initial userns. By default such mounts have the SB_I_NODEV flag + * set in s_iflags to prevent security issues where userns root can + * just create random device nodes via mknod() since it owns the + * filesystem mount. But binderfs does not allow to create any files + * including devices nodes. The only way to create binder devices nodes + * is through the binder-control device which userns root is explicitly + * allowed to do. So removing the SB_I_NODEV flag from s_iflags is both + * necessary and safe. + */ + sb->s_iflags &= ~SB_I_NODEV; + sb->s_iflags |= SB_I_NOEXEC; + sb->s_magic = BINDERFS_SUPER_MAGIC; + sb->s_op = &binderfs_super_ops; + sb->s_time_gran = 1; + + sb->s_fs_info = kzalloc(sizeof(struct binderfs_info), GFP_KERNEL); + if (!sb->s_fs_info) + return -ENOMEM; + info = sb->s_fs_info; + + info->ipc_ns = get_ipc_ns(current->nsproxy->ipc_ns); + + info->root_gid = make_kgid(sb->s_user_ns, 0); + if (!gid_valid(info->root_gid)) + info->root_gid = GLOBAL_ROOT_GID; + info->root_uid = make_kuid(sb->s_user_ns, 0); + if (!uid_valid(info->root_uid)) + info->root_uid = GLOBAL_ROOT_UID; + info->mount_opts.max = ctx->max; + info->mount_opts.stats_mode = ctx->stats_mode; + + inode = new_inode(sb); + if (!inode) + return -ENOMEM; + + inode->i_ino = FIRST_INODE; + inode->i_fop = &simple_dir_operations; + inode->i_mode = S_IFDIR | 0755; + inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode); + inode->i_op = &binderfs_dir_inode_operations; + set_nlink(inode, 2); + + sb->s_root = d_make_root(inode); + if (!sb->s_root) + return -ENOMEM; + + ret = binderfs_binder_ctl_create(sb); + if (ret) + return ret; + + name = binder_devices_param; + for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) { + strscpy(device_info.name, name, len + 1); + ret = binderfs_binder_device_create(inode, NULL, &device_info); + if (ret) + return ret; + name += len; + if (*name == ',') + name++; + } + + if (info->mount_opts.stats_mode == binderfs_stats_mode_global) + return init_binder_logs(sb); + + return 0; +} + +static int binderfs_fs_context_get_tree(struct fs_context *fc) +{ + return get_tree_nodev(fc, binderfs_fill_super); +} + +static void binderfs_fs_context_free(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx = fc->fs_private; + + kfree(ctx); +} + +static const struct fs_context_operations binderfs_fs_context_ops = { + .free = binderfs_fs_context_free, + .get_tree = binderfs_fs_context_get_tree, + .parse_param = binderfs_fs_context_parse_param, + .reconfigure = binderfs_fs_context_reconfigure, +}; + +static int binderfs_init_fs_context(struct fs_context *fc) +{ + struct binderfs_mount_opts *ctx; + + ctx = kzalloc(sizeof(struct binderfs_mount_opts), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->max = BINDERFS_MAX_MINOR; + ctx->stats_mode = binderfs_stats_mode_unset; + + fc->fs_private = ctx; + fc->ops = &binderfs_fs_context_ops; + + return 0; +} + +static struct file_system_type binder_fs_type = { + .name = "binder", + .init_fs_context = binderfs_init_fs_context, + .parameters = binderfs_fs_parameters, + .kill_sb = kill_litter_super, + .fs_flags = FS_USERNS_MOUNT, +}; + +int __init init_binderfs(void) +{ + int ret; + const char *name; + size_t len; + + /* Verify that the default binderfs device names are valid. */ + name = binder_devices_param; + for (len = strcspn(name, ","); len > 0; len = strcspn(name, ",")) { + if (len > BINDERFS_MAX_NAME) + return -E2BIG; + name += len; + if (*name == ',') + name++; + } + + /* Allocate new major number for binderfs. */ + ret = alloc_chrdev_region(&binderfs_dev, 0, BINDERFS_MAX_MINOR, + "binder"); + if (ret) + return ret; + + ret = register_filesystem(&binder_fs_type); + if (ret) { + unregister_chrdev_region(binderfs_dev, BINDERFS_MAX_MINOR); + return ret; + } + + return ret; +} + +void __exit exit_binderfs(void) +{ + unregister_filesystem(&binder_fs_type); + unregister_chrdev_region(binderfs_dev, BINDERFS_MAX_MINOR); +} + +MODULE_LICENSE("GPL v2"); diff --git a/binder/deps.c b/binder/deps.c index 6daef72..68ccffe 100644 --- a/binder/deps.c +++ b/binder/deps.c @@ -2,6 +2,7 @@ #include #include #include +#include #include #include #include @@ -9,6 +10,8 @@ #include #include +#include "deps.h" + #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0)) #ifndef CONFIG_KPROBES @@ -66,103 +69,16 @@ static unsigned long kallsyms_lookup_name_wrapper(const char *name) } -static struct vm_struct *(*get_vm_area_ptr)(unsigned long, unsigned long) = NULL; -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) -static void (*zap_page_range_ptr)(struct vm_area_struct *, unsigned long, unsigned long) = NULL; -#else -static void (*zap_page_range_ptr)(struct vm_area_struct *, unsigned long, unsigned long, struct zap_details *) = NULL; -#endif -static int (*map_kernel_range_noflush_ptr)(unsigned long start, unsigned long size, pgprot_t prot, struct page **pages) = NULL; -static void (*unmap_kernel_range_ptr)(unsigned long, unsigned long) = NULL; -static struct files_struct *(*get_files_struct_ptr)(struct task_struct *) = NULL; -static void (*put_files_struct_ptr)(struct files_struct *) = NULL; -static struct sighand_struct *(*__lock_task_sighand_ptr)(struct task_struct *, unsigned long *) = NULL; -static int (*__alloc_fd_ptr)(struct files_struct *files, unsigned start, unsigned end, unsigned flags) = NULL; -static void (*__fd_install_ptr)(struct files_struct *files, unsigned int fd, struct file *file) = NULL; -static int (*__close_fd_ptr)(struct files_struct *files, unsigned int fd) = NULL; +static int (*__close_fd_get_file_ptr)(unsigned int fd, struct file **res) = NULL; + +int __close_fd_get_file(unsigned int fd, struct file **res) +{ + if (!__close_fd_get_file_ptr) + __close_fd_get_file_ptr = kallsyms_lookup_name_wrapper("__close_fd_get_file"); + return __close_fd_get_file_ptr(fd, res); +} + static int (*can_nice_ptr)(const struct task_struct *, const int) = NULL; -static int (*security_binder_set_context_mgr_ptr)(struct task_struct *mgr) = NULL; -static int (*security_binder_transaction_ptr)(struct task_struct *from, struct task_struct *to) = NULL; -static int (*security_binder_transfer_binder_ptr)(struct task_struct *from, struct task_struct *to) = NULL; -static int (*security_binder_transfer_file_ptr)(struct task_struct *from, struct task_struct *to, struct file *file) = NULL; - -struct vm_struct *get_vm_area(unsigned long size, unsigned long flags) -{ - if (!get_vm_area_ptr) - get_vm_area_ptr = kallsyms_lookup_name_wrapper("get_vm_area"); - return get_vm_area_ptr(size, flags); -} - -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) -void zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size) -#else -void zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size, struct zap_details *details) -#endif -{ - if (!zap_page_range_ptr) - zap_page_range_ptr = kallsyms_lookup_name_wrapper("zap_page_range"); -#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) - zap_page_range_ptr(vma, address, size); -#else - zap_page_range_ptr(vma, address, size, details); -#endif -} - -int map_kernel_range_noflush(unsigned long start, unsigned long size, pgprot_t prot, struct page **pages) -{ - if (!map_kernel_range_noflush_ptr) - map_kernel_range_noflush_ptr = kallsyms_lookup_name_wrapper("map_kernel_range_noflush"); - return map_kernel_range_noflush_ptr(start, size, prot, pages); -} - -void unmap_kernel_range(unsigned long addr, unsigned long size) -{ - if (!unmap_kernel_range_ptr) - unmap_kernel_range_ptr = kallsyms_lookup_name_wrapper("unmap_kernel_range"); - unmap_kernel_range_ptr(addr, size); -} - -struct files_struct *get_files_struct(struct task_struct *task) -{ - if (!get_files_struct_ptr) - get_files_struct_ptr = kallsyms_lookup_name_wrapper("get_files_struct"); - return get_files_struct_ptr(task); -} - -void put_files_struct(struct files_struct *files) -{ - if (!put_files_struct_ptr) - put_files_struct_ptr = kallsyms_lookup_name_wrapper("put_files_struct"); - put_files_struct_ptr(files); -} - -struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, unsigned long *flags) -{ - if (!__lock_task_sighand_ptr) - __lock_task_sighand_ptr = kallsyms_lookup_name_wrapper("__lock_task_sighand"); - return __lock_task_sighand_ptr(tsk, flags); -} - -int __alloc_fd(struct files_struct *files, unsigned start, unsigned end, unsigned flags) -{ - if (!__alloc_fd_ptr) - __alloc_fd_ptr = kallsyms_lookup_name_wrapper("__alloc_fd"); - return __alloc_fd_ptr(files, start, end, flags); -} - -void __fd_install(struct files_struct *files, unsigned int fd, struct file *file) -{ - if (!__fd_install_ptr) - __fd_install_ptr = kallsyms_lookup_name_wrapper("__fd_install"); - __fd_install_ptr(files, fd, file); -} - -int __close_fd(struct files_struct *files, unsigned int fd) -{ - if (!__close_fd_ptr) - __close_fd_ptr = kallsyms_lookup_name_wrapper("__close_fd_ptr"); - return __close_fd_ptr(files, fd); -} int can_nice(const struct task_struct *p, const int nice) { @@ -171,6 +87,17 @@ int can_nice(const struct task_struct *p, const int nice) return can_nice_ptr(p, nice); } +static void (*mmput_async_ptr)(struct mm_struct *mm) = NULL; + +void mmput_async(struct mm_struct *mm) +{ + if (!mmput_async_ptr) + mmput_async_ptr = kallsyms_lookup_name_wrapper("mmput_async"); + return mmput_async_ptr(mm); +} + +static int (*security_binder_set_context_mgr_ptr)(struct task_struct *mgr) = NULL; + int security_binder_set_context_mgr(struct task_struct *mgr) { if (!security_binder_set_context_mgr_ptr) @@ -178,6 +105,8 @@ int security_binder_set_context_mgr(struct task_struct *mgr) return security_binder_set_context_mgr_ptr(mgr); } +static int (*security_binder_transaction_ptr)(struct task_struct *from, struct task_struct *to) = NULL; + int security_binder_transaction(struct task_struct *from, struct task_struct *to) { if (!security_binder_transaction_ptr) @@ -185,6 +114,8 @@ int security_binder_transaction(struct task_struct *from, struct task_struct *to return security_binder_transaction_ptr(from, to); } +static int (*security_binder_transfer_binder_ptr)(struct task_struct *from, struct task_struct *to) = NULL; + int security_binder_transfer_binder(struct task_struct *from, struct task_struct *to) { if (!security_binder_transfer_binder_ptr) @@ -192,9 +123,49 @@ int security_binder_transfer_binder(struct task_struct *from, struct task_struct return security_binder_transfer_binder_ptr(from, to); } +static int (*security_binder_transfer_file_ptr)(struct task_struct *from, struct task_struct *to, struct file *file) = NULL; + int security_binder_transfer_file(struct task_struct *from, struct task_struct *to, struct file *file) { if (!security_binder_transfer_file_ptr) security_binder_transfer_file_ptr = kallsyms_lookup_name_wrapper("security_binder_transfer_file"); return security_binder_transfer_file_ptr(from, to, file); } + +static int (*task_work_add_ptr)(struct task_struct *task, struct callback_head *work, + enum task_work_notify_mode notify) = NULL; + +int task_work_add(struct task_struct *task, struct callback_head *work, + enum task_work_notify_mode notify) +{ + if (!task_work_add_ptr) + task_work_add_ptr = kallsyms_lookup_name_wrapper("task_work_add"); + return task_work_add_ptr(task, work, notify); +} + +static void (*zap_page_range_ptr)(struct vm_area_struct *, unsigned long, unsigned long) = NULL; + +void zap_page_range(struct vm_area_struct *vma, unsigned long address, unsigned long size) +{ + if (!zap_page_range_ptr) + zap_page_range_ptr = kallsyms_lookup_name_wrapper("zap_page_range"); + zap_page_range_ptr(vma, address, size); +} + +static void (*put_ipc_ns_ptr)(struct ipc_namespace *ns) = NULL; + +void put_ipc_ns(struct ipc_namespace *ns) +{ + if (!put_ipc_ns_ptr) + put_ipc_ns_ptr = kallsyms_lookup_name_wrapper("put_ipc_ns"); + put_ipc_ns_ptr(ns); +} + +static struct ipc_namespace *init_ipc_ns_ptr = NULL; + +struct ipc_namespace *get_init_ipc_ns_ptr(void) +{ + if (!init_ipc_ns_ptr) + init_ipc_ns_ptr = kallsyms_lookup_name_wrapper("init_ipc_ns"); + return init_ipc_ns_ptr; +} diff --git a/binder/deps.h b/binder/deps.h new file mode 100644 index 0000000..771e268 --- /dev/null +++ b/binder/deps.h @@ -0,0 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include + +struct ipc_namespace* get_init_ipc_ns_ptr(void);