From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH] ip_tunnel: fix kernel panic with icmp_dest_unreach Date: Sat, 25 May 2013 23:27:08 -0700 (PDT) Message-ID: <20130525.232708.324081198009097189.davem@davemloft.net> References: <1369324409.3301.382.camel@edumazet-glaptop> <1369329033.3301.389.camel@edumazet-glaptop> <1369410598.3301.415.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: daniel.petre@rcs-rds.ro, netdev@vger.kernel.org To: eric.dumazet@gmail.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:44625 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755334Ab3EZG1J (ORCPT ); Sun, 26 May 2013 02:27:09 -0400 In-Reply-To: <1369410598.3301.415.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Fri, 24 May 2013 08:49:58 -0700 > From: Eric Dumazet > > Daniel Petre reported crashes in icmp_dst_unreach() with following call > graph: ... > Daniel found a similar problem mentioned in > http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html > > And indeed this is the root cause : skb->cb[] contains data fooling IP > stack. > > We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure() > is called. Or else skb->cb[] might contain garbage from GSO segmentation > layer. > > A similar fix was tested on linux-3.9, but gre code was refactored in > linux-3.10. I'll send patches for stable kernels as well. > > Many thanks to Daniel for providing reports, patches and testing ! > > Reported-by: Daniel Petre > Signed-off-by: Eric Dumazet Applied, thanks a lot everyone.