208 lines
6.8 KiB
C
208 lines
6.8 KiB
C
#include <linux/task_work.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/file.h>
|
|
#include <linux/fdtable.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/ipc_namespace.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/kprobes.h>
|
|
#include <linux/version.h>
|
|
#include <linux/task_work.h>
|
|
|
|
#include "deps.h"
|
|
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0))
|
|
|
|
#ifndef CONFIG_KPROBES
|
|
# error "Your kernel does not support KProbes, but this is required to compile binder as a kernel module on kernel 5.7 and later"
|
|
#endif
|
|
|
|
typedef unsigned long (*kallsyms_lookup_name_t)(const char *name);
|
|
|
|
static int dummy_kprobe_handler(struct kprobe *p, struct pt_regs *regs)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static kallsyms_lookup_name_t get_kallsyms_lookup_name_ptr(void)
|
|
{
|
|
struct kprobe probe;
|
|
int ret;
|
|
kallsyms_lookup_name_t addr;
|
|
|
|
memset(&probe, 0, sizeof(probe));
|
|
probe.pre_handler = dummy_kprobe_handler;
|
|
probe.symbol_name = "kallsyms_lookup_name";
|
|
ret = register_kprobe(&probe);
|
|
if (ret)
|
|
return NULL;
|
|
addr = (kallsyms_lookup_name_t) probe.addr;
|
|
unregister_kprobe(&probe);
|
|
|
|
return addr;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* On kernel 5.7 and later, kallsyms_lookup_name() can no longer be called from a kernel
|
|
* module for reasons described here: https://lwn.net/Articles/813350/
|
|
* As binder really needs to use kallsysms_lookup_name() to access some kernel
|
|
* functions that otherwise wouldn't be accessible, KProbes are used on later
|
|
* kernels to get the address of kallsysms_lookup_name(). The function is
|
|
* afterwards used just as before. This is a very dirty hack though and the much
|
|
* better solution would be if all the functions that are currently resolved
|
|
* with kallsysms_lookup_name() would get an EXPORT_SYMBOL() annotation to
|
|
* make them directly accessible to kernel modules.
|
|
*/
|
|
static unsigned long kallsyms_lookup_name_wrapper(const char *name)
|
|
{
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,7,0))
|
|
static kallsyms_lookup_name_t func_ptr = NULL;
|
|
if (!func_ptr)
|
|
func_ptr = get_kallsyms_lookup_name_ptr();
|
|
|
|
return func_ptr(name);
|
|
#else
|
|
return kallsyms_lookup_name(name);
|
|
#endif
|
|
}
|
|
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,19,0))
|
|
static struct file *(*close_fd_get_file_ptr)(unsigned int fd)
|
|
#else
|
|
static int (*close_fd_get_file_ptr)(unsigned int fd, struct file **res)
|
|
#endif
|
|
= NULL;
|
|
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,8,0))
|
|
struct file *file_close_fd(unsigned int fd)
|
|
#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(5,19,0))
|
|
struct file *close_fd_get_file(unsigned int fd)
|
|
#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(5,11,0))
|
|
int close_fd_get_file(unsigned int fd, struct file **res)
|
|
#else
|
|
int __close_fd_get_file(unsigned int fd, struct file **res)
|
|
#endif
|
|
{
|
|
if (!close_fd_get_file_ptr)
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,8,0))
|
|
close_fd_get_file_ptr = kallsyms_lookup_name_wrapper("file_close_fd");
|
|
#elif (LINUX_VERSION_CODE >= KERNEL_VERSION(5,11,0))
|
|
close_fd_get_file_ptr = kallsyms_lookup_name_wrapper("close_fd_get_file");
|
|
#else
|
|
close_fd_get_file_ptr = kallsyms_lookup_name_wrapper("__close_fd_get_file");
|
|
#endif
|
|
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,19,0))
|
|
return close_fd_get_file_ptr(fd);
|
|
#else
|
|
return close_fd_get_file_ptr(fd, res);
|
|
#endif
|
|
}
|
|
|
|
static int (*can_nice_ptr)(const struct task_struct *, const int) = NULL;
|
|
|
|
int can_nice(const struct task_struct *p, const int nice)
|
|
{
|
|
if (!can_nice_ptr)
|
|
can_nice_ptr = kallsyms_lookup_name_wrapper("can_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)
|
|
security_binder_set_context_mgr_ptr = kallsyms_lookup_name_wrapper("security_binder_set_context_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)
|
|
security_binder_transaction_ptr = kallsyms_lookup_name_wrapper("security_binder_transaction");
|
|
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)
|
|
security_binder_transfer_binder_ptr = kallsyms_lookup_name_wrapper("security_binder_transfer_binder");
|
|
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);
|
|
}
|
|
|
|
#if (LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0))
|
|
static void (*zap_page_range_single_ptr)(struct vm_area_struct *, unsigned long, unsigned long, struct zap_details *) = NULL;
|
|
|
|
void zap_page_range_single(struct vm_area_struct *vma, unsigned long address, unsigned long size, struct zap_details *details)
|
|
{
|
|
if (!zap_page_range_single_ptr)
|
|
zap_page_range_single_ptr = kallsyms_lookup_name_wrapper("zap_page_range_single");
|
|
zap_page_range_single_ptr(vma, address, size, details);
|
|
}
|
|
#else
|
|
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);
|
|
}
|
|
#endif
|
|
|
|
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;
|
|
}
|