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Date: Mon, 01 Jul 2013 13:36:15 -0700 (PDT)
Message-Id: <20130701.133615.366371022223254228.davem@davemloft.net>
To: eric.dumazet@gmail.com
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Subject: Re: kernel panic in skb_copy_bits
From: David Miller <davem@davemloft.net>
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 28 Jun 2013 02:37:42 -0700

> [PATCH] neighbour: fix a race in neigh_destroy()
> 
> There is a race in neighbour code, because neigh_destroy() uses
> skb_queue_purge(&neigh->arp_queue) without holding neighbour lock,
> while other parts of the code assume neighbour rwlock is what
> protects arp_queue
> 
> Convert all skb_queue_purge() calls to the __skb_queue_purge() variant
> 
> Use __skb_queue_head_init() instead of skb_queue_head_init()
> to make clear we do not use arp_queue.lock
> 
> And hold neigh->lock in neigh_destroy() to close the race.
> 
> Reported-by: Joe Jin <joe.jin@oracle.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable, thanks Eric.