From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: =?UTF-8?Q?=E7=AD=94=E5=A4=8D=3A?= [PATCH] set fake_rtable's
 dst to NULL to avoid kernel Oops.
Date: Thu, 29 Mar 2012 10:52:00 +0200
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To: "Peter Huang (Peng)" <peter.huangpeng@huawei.com>
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On Thu, 2012-03-29 at 14:40 +0800, Peter Huang (Peng) wrote:
> We already check current kernel-3.3, it has the same problem.
> 
> I am not very sure that if this modify could cause other problems or not,
> Because I don't know where fake_rtable was used.


Check net/bridge/br_netfilter.c and commits e688a6048076 (net: introduce
DST_NOPEER dst flag )  4adf0af6818f3ea5 (bridge: send correct MTU value
in PMTU (revised))

Apparently bug is because struct net_bridge is freed while its embedded
fake_rtable is still used by some packets.

I am not sure we are allowed to NULLify skb->dst, it might break
netfilter.

Maybe real fix would be to use a non embedded dst.