audit: make sure we never skip the multicast broadcast

When the auditd connection is reset, either intentionally or due to
a failure, any records that were in the main backlog queue would not
be sent in a multicast broadcast.  This patch fixes this problem by
not flushing the main backlog queue on a connection reset, the main
kauditd_thread() will take care of that normally.

Resolves: https://github.com/linux-audit/audit-kernel/issues/41Reviewed-by: NRichard Guy Briggs <rgb@redhat.com>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

kernel/audit.c

@@ -605,11 +605,10 @@ static void auditd_reset(const struct auditd_connection *ac)
 	if (ac_old)
 		call_rcu(&ac_old->rcu, auditd_conn_free);
 
-	/* flush all of the main and retry queues to the hold queue */
+	/* flush the retry queue to the hold queue, but don't touch the main
+	 * queue since we need to process that normally for multicast */
 	while ((skb = skb_dequeue(&audit_retry_queue)))
 		kauditd_hold_skb(skb);
-	while ((skb = skb_dequeue(&audit_queue)))
-		kauditd_hold_skb(skb);
 }
 
 /**