Commit a4731138 authored May 27, 2010 by Eric Dumazet Committed by David S. Miller May 28, 2010

net: fix __neigh_event_send()



commit 7fee226a (net: add a noref bit on skb dst) missed one spot
where an skb is enqueued, with a possibly not refcounted dst entry.

__neigh_event_send() inserts skb into arp_queue, so we must make sure
dst entry is refcounted, or dst entry can be freed by garbage collector
after caller exits from rcu protected section.

Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent a02c3789

net/core/neighbour.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -934,6 +934,7 @@ int __neigh_event_send(struct neighbour neigh, struct sk_buff skb)
		kfree_skb(buff);
		NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
		}
		skb_dst_force(skb);
		__skb_queue_tail(&neigh->arp_queue, skb);
		}
		rc = 1;

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