diff mbox

[libibverbs,v2,06/11] read_config_file(): check opened file

Message ID bf328dc9243fd70a41942c1ad101c065783319cf.1375952089.git.ydroneaud@opteya.com (mailing list archive)
State Rejected
Headers show

Commit Message

Yann Droneaud Aug. 8, 2013, 7:40 p.m. UTC 
Use fstat() to check the parameters of the opened file instead
of checking the path. This is basic Time-Of-Check / Time-Of-Use
(TOCTOU) issue.

Weakness addressed:

- CWE-363: Race Condition Enabling Link Following
<http://cwe.mitre.org/data/definitions/363.html>

- CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition
<http://cwe.mitre.org/data/definitions/367.html>

Secure coding:

- FIO01-C. Be careful using functions that use file names for identification
<https://www.securecoding.cert.org/confluence/display/seccode/FIO01-C.+Be+careful+using+functions+that+use+file+names+for+identification>

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
---
 src/init.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)
diff mbox

Patch

diff --git a/src/init.c b/src/init.c
index c260628..150adcf 100644
--- a/src/init.c
+++ b/src/init.c
@@ -246,23 +246,23 @@  static void read_config_file(int conf_dirfd, const char *name)
 	ssize_t len;
 	struct stat buf;
 
-	if (fstatat(conf_dirfd, name, &buf, 0)) {
-		fprintf(stderr, PFX "Warning: couldn't stat config file '%s/%s'.\n",
+	fd = openat(conf_dirfd, name, O_RDONLY | O_CLOEXEC);
+	if (fd == -1) {
+		fprintf(stderr, PFX "Warning: couldn't read config file '%s/%s'.\n",
 			IBV_CONFIG_DIR, name);
 		return;
 	}
 
-	if (!S_ISREG(buf.st_mode)) {
-		fprintf(stderr, PFX "Warning: invalid config file '%s/%s'.\n",
+	if (fstat(fd, &buf)) {
+		fprintf(stderr, PFX "Warning: couldn't stat config file '%s/%s'.\n",
 			IBV_CONFIG_DIR, name);
-		return;
+		goto out;
 	}
 
-	fd = openat(conf_dirfd, name, O_RDONLY | O_CLOEXEC);
-	if (fd == -1) {
-		fprintf(stderr, PFX "Warning: couldn't read config file '%s/%s'.\n",
+	if (!S_ISREG(buf.st_mode)) {
+		fprintf(stderr, PFX "Warning: invalid config file '%s/%s'.\n",
 			IBV_CONFIG_DIR, name);
-		return;
+		goto out;
 	}
 
 	conf = fdopen(fd, "r" STREAM_CLOEXEC);