alistair23-linux/tools/perf/util/sysfs.c
Thomas Jarosch a65c234206 perf tools: Fix possible (unlikely) buffer overflow
cppcheck reported:
[tools/perf/util/sysfs.c:50]: (error) Width 4096 given in format string
(no. 1) is larger than destination buffer 'sysfs_mountpoint[4096]',
use %4095s to prevent overflowing it

-> All other places in the kernel that use STR(PATH_MAX)
   have a buffer size of PATH_MAX + 1.

Signed-off-by: Thomas Jarosch <thomas.jarosch@intra2net.com>
Link: http://lkml.kernel.org/r/50D9D30B.8090002@intra2net.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2013-01-24 16:40:18 -03:00

61 lines
1.1 KiB
C

#include "util.h"
#include "sysfs.h"
static const char * const sysfs_known_mountpoints[] = {
"/sys",
0,
};
static int sysfs_found;
char sysfs_mountpoint[PATH_MAX + 1];
static int sysfs_valid_mountpoint(const char *sysfs)
{
struct statfs st_fs;
if (statfs(sysfs, &st_fs) < 0)
return -ENOENT;
else if (st_fs.f_type != (long) SYSFS_MAGIC)
return -ENOENT;
return 0;
}
const char *sysfs_find_mountpoint(void)
{
const char * const *ptr;
char type[100];
FILE *fp;
if (sysfs_found)
return (const char *) sysfs_mountpoint;
ptr = sysfs_known_mountpoints;
while (*ptr) {
if (sysfs_valid_mountpoint(*ptr) == 0) {
sysfs_found = 1;
strcpy(sysfs_mountpoint, *ptr);
return sysfs_mountpoint;
}
ptr++;
}
/* give up and parse /proc/mounts */
fp = fopen("/proc/mounts", "r");
if (fp == NULL)
return NULL;
while (!sysfs_found &&
fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
sysfs_mountpoint, type) == 2) {
if (strcmp(type, "sysfs") == 0)
sysfs_found = 1;
}
fclose(fp);
return sysfs_found ? sysfs_mountpoint : NULL;
}