BACKPORT: smack: call WARN_ONCE() instead of calling audit_log_start()

Remove the call to audit_log() (which call audit_log_start()) and deal with
the errors in the caller, logging only once if the condition is met.  Calling
audit_log_start() in this location makes buffer allocation and locking more
complicated in the calling tree (audit_filter_user()).

Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
(cherry-picked from upstream 4eb0f4abfb9441849530ea19389ae57cc62c8078)

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index b6105f1e94f27f0755834028f380f6db66679601..c29c164b9cc77357a6d35b3badb0390b7255b8cf 100644 (file)
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3631,9 +3631,8 @@ static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule,
        struct smack_known *skp;
        char *rule = vrule;
 
-       if (!rule) {
-               audit_log(actx, GFP_KERNEL, AUDIT_SELINUX_ERR,
-                         "Smack: missing rule\n");
+       if (unlikely(!rule)) {
+               WARN_ONCE(1, "Smack: missing rule\n");
                return -ENOENT;
        }