[i-g-t,7/7] Avoid truncate string in __igt_lsof_fds

Commit Message

Rodrigo Siqueira July 7, 2018, 11:23 p.m. UTC

Note that 'proc_path' parameter in __igt_lsof_fds receives a string
which was initialized with the size of PATH_MAX and the local variable
'path' has the same size, but it also have to append: '/', '\0', and the
directory name. This situation caused the warning described below.

warning: ‘%s’ directive output may be truncated writing up to 255 bytes
into a region of size between 0 and 4095 [-Wformat-truncation=]
snprintf(path, sizeof(path), "%s/%s", proc_path, d->d_name);
note: ‘snprintf’ output between 2 and 4352 bytes into a destination of
size 4096 [..]

This commit fixes this problem by changing the string size passed by
__igt_lsoft to __igt_lsof_fds. The max size for the string is
strlen("/proc/%d/cwd")+1 where "%d" can be estimated with
CEILING(LOG_10(INT_MAX)), in this sense, it is safe to define a path
size of 30 characters.

Signed-off-by: Rodrigo Siqueira <[e-mail]>
---
 lib/igt_aux.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

diff --git a/lib/igt_aux.c b/lib/igt_aux.c
index ca8ccfbd..d9dbf7ce 100644
--- a/lib/igt_aux.c
+++ b/lib/igt_aux.c
@@ -1485,7 +1485,7 @@  __igt_lsof(const char *dir)
 	PROCTAB *proc;
 	proc_t *proc_info;
 
-	char path[PATH_MAX];
+	char path[30];
 	char *name_lnk;
 	struct stat st;
 	int state = 0;