When auditd is congested the kernel's audit system leaks skb's.  First,
it takes them off the audit_buffer sklist at which point they are lost,
second, it allocates a new skb with 0 length payload.  Then (likely still
congested), it repeats this losing the new skb.  Plug the leak by making
sure to requeue the skb, and avoid audit_log_move() on 0 len audit_buffer.

Signed-off-by: Chris Wright <[EMAIL PROTECTED]>

===== kernel/audit.c 1.6 vs edited =====
--- 1.6/kernel/audit.c  2005-01-20 20:56:04 -08:00
+++ edited/kernel/audit.c       2005-01-25 14:34:32 -08:00
@@ -494,6 +494,10 @@ static void audit_log_move(struct audit_
        char            *start;
        int             extra = ab->nlh ? 0 : NLMSG_SPACE(0);
 
+       /* possible resubmission */
+       if (ab->len == 0)
+               return;
+
        skb = skb_peek(&ab->sklist);
        if (!skb || skb_tailroom(skb) <= ab->len + extra) {
                skb = alloc_skb(2 * ab->len + extra, GFP_ATOMIC);
@@ -535,6 +539,7 @@ static inline int audit_log_drain(struct
                }
                if (retval == -EAGAIN && ab->count < 5) {
                        ++ab->count;
+                       skb_queue_tail(&ab->sklist, skb);
                        audit_log_end_irq(ab);
                        return 1;
                }
-
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