From 08e6b0cb8b8c27bed303503bfeec4b405b8f49b5 Mon Sep 17 00:00:00 2001
From: Doug MacEachern <dougm@hyperic.com>
Date: Sat, 12 Feb 2005 01:50:56 +0000
Subject: [PATCH] check /dev/kmem perms

---
 src/os/darwin/darwin_sigar.c | 32 ++++++++++++++++++++++++++------
 src/os/darwin/sigar_os.h     |  2 ++
 2 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/src/os/darwin/darwin_sigar.c b/src/os/darwin/darwin_sigar.c
index ac95bbf8..7b3286fc 100644
--- a/src/os/darwin/darwin_sigar.c
+++ b/src/os/darwin/darwin_sigar.c
@@ -43,6 +43,10 @@ static int get_koffsets(sigar_t *sigar)
         { NULL }
     };
 
+    if (!sigar->kmem) {
+        return SIGAR_EPERM_KMEM;
+    }
+
     kvm_nlist(sigar->kmem, klist);
     if (klist[0].n_type == 0) {
         return errno;
@@ -57,11 +61,9 @@ static int get_koffsets(sigar_t *sigar)
 
 static int kread(sigar_t *sigar, void *data, int size, long offset)
 {
-#if 0
-    if (sigar->kmem < 0) {
+    if (!sigar->kmem) {
         return SIGAR_EPERM_KMEM;
     }
-#endif
 
     if (kvm_read(sigar->kmem, offset, data, size) != size) {
         return errno;
@@ -126,7 +128,12 @@ int sigar_os_close(sigar_t *sigar)
 
 char *sigar_os_error_string(int err)
 {
-    return NULL;
+    switch (err) {
+      case SIGAR_EPERM_KMEM:
+        return "Failed to open /dev/kmem for reading";
+      default:
+        return NULL;
+    }
 }
 
 int sigar_mem_get(sigar_t *sigar, sigar_mem_t *mem)
@@ -251,6 +258,10 @@ int sigar_swap_get(sigar_t *sigar, sigar_swap_t *swap)
 #else
     struct kvm_swap kswap[1];
 
+    if (!sigar->kmem) {
+        return SIGAR_EPERM_KMEM;
+    }
+
     if (kvm_getswapinfo(sigar->kmem, kswap, 1, 0) < 0) {
         return errno;
     }
@@ -375,8 +386,13 @@ int sigar_proc_list_get(sigar_t *sigar,
     return SIGAR_OK;
 #else
     int i, num;
-    struct kinfo_proc *proc =
-        kvm_getprocs(sigar->kmem, KERN_PROC_ALL, 0, &num);
+    struct kinfo_proc *proc;
+
+    if (!sigar->kmem) {
+        return SIGAR_EPERM_KMEM;
+    }
+
+    proc = kvm_getprocs(sigar->kmem, KERN_PROC_ALL, 0, &num);
     
     proclist->number = 0;
     proclist->size = num;
@@ -625,6 +641,10 @@ int sigar_proc_env_get(sigar_t *sigar, sigar_pid_t pid,
     struct kinfo_proc *pinfo;
     int num;
 
+    if (!sigar->kmem) {
+        return SIGAR_EPERM_KMEM;
+    }
+
     pinfo = kvm_getprocs(sigar->kmem, KERN_PROC_PID, pid, &num);
     if (!pinfo || (num < 1)) {
         return errno;
diff --git a/src/os/darwin/sigar_os.h b/src/os/darwin/sigar_os.h
index e9ca4ce3..dff54d80 100644
--- a/src/os/darwin/sigar_os.h
+++ b/src/os/darwin/sigar_os.h
@@ -31,4 +31,6 @@ struct sigar_t {
 #endif
 };
 
+#define SIGAR_EPERM_KMEM (SIGAR_OS_START_ERROR+1)
+
 #endif /* SIGAR_OS_H */