audit: move calcs after alloc and check when logging set loginuid

Move the calculations of values after the allocation in case the allocation fails. This avoids wasting effort in the rare case that it fails, but more importantly saves us extra logic to release the tty ref. Signed-off-by: Richard Guy Briggs <[email protected]> Signed-off-by: Paul Moore <[email protected]>
maraz · Jun 28, 2016 · 76a658c · 76a658c
1 parent 188e3c5
commit 76a658c
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
@@ -1985,14 +1985,15 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
 	if (!audit_enabled)
 		return;
 
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
+	if (!ab)
+		return;
+
 	uid = from_kuid(&init_user_ns, task_uid(current));
 	oldloginuid = from_kuid(&init_user_ns, koldloginuid);
 	loginuid = from_kuid(&init_user_ns, kloginuid),
 	tty = audit_get_tty(current);
 
-	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
-	if (!ab)
-		return;
 	audit_log_format(ab, "pid=%d uid=%u", task_pid_nr(current), uid);
 	audit_log_task_context(ab);
 	audit_log_format(ab, " old-auid=%u auid=%u tty=%s old-ses=%u ses=%u res=%d",