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 <chrisw@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>