[PATCH 1/3] selinux: call WARN_ONCE() instead of calling audit_log_start()

Richard Guy Briggs
2013-12-05T02:45:54Z

Two of the conditions in selinux_audit_rule_match() should never happen and
the third indicates a race that should be retried. Remove the calls 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>
---
security/selinux/ss/services.c | 12 ++++--------
1 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index b4feecc..f4dda05 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2938,25 +2938,21 @@ int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
struct selinux_audit_rule *rule = vrule;
int match = 0;

- if (!rule) {
- audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
- "selinux_audit_rule_match: missing rule\n");
+ if (unlikely(!rule)) {
+ WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n");
return -ENOENT;
}

read_lock(&policy_rwlock);

if (rule->au_seqno < latest_granting) {
- audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
- "selinux_audit_rule_match: stale rule\n");
match = -ESTALE;
goto out;
}

ctxt = sidtab_search(&sidtab, sid);
- if (!ctxt) {
- audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
- "selinux_audit_rule_match: unrecognized SID %d\n",
+ if (unlikely(!ctxt)) {
+ WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n",
sid);
match = -ENOENT;
goto out;
--
1.7.1