From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: ipt_SYNPROXY: kernel panic caused by nullpointer dereference Date: Wed, 11 Dec 2013 11:33:04 +0100 Message-ID: <20131211103304.GA7540@localhost> References: <20131208100146.GA3840@localhost> <20131208165231.GA1564@macbook.localnet> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Nicki P." , netfilter-devel@vger.kernel.org To: Patrick McHardy Return-path: Received: from mail.us.es ([193.147.175.20]:60626 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751109Ab3LKKdL (ORCPT ); Wed, 11 Dec 2013 05:33:11 -0500 Content-Disposition: inline In-Reply-To: <20131208165231.GA1564@macbook.localnet> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Sun, Dec 08, 2013 at 04:52:31PM +0000, Patrick McHardy wrote: > On Sun, Dec 08, 2013 at 11:01:46AM +0100, Pablo Neira Ayuso wrote: > > On Sun, Dec 08, 2013 at 08:16:00AM +0100, Nicki P. wrote: > > > hi, > > > > > > when activating ipt_SYNPROXY with: > > > iptables -t raw -A PREROUTING -p tcp -d 1.2.3.4 --dport 80 --tcp-flags > > > SYN,ACK,RST,FIN SYN -j SYNPROXY > > > > > > and sending a SYN packet to port 80: > > > hping3 -S -d 64 1.2.3.4 -p 80 > > > > > > I get kernel panic: > > > http://goo.gl/L6dCz6 > > > > > > I'm using kernel v3.12.2 and iptables v1.4.21. Am I doing something wrong, > > > or is it a bug? > > > > You have to run this from the INPUT/FORWARD chain, SYNPROXY needs the > > routing information to work. > > Let's fix that: > > From e5b31e75df3c3f9629900016a95336c04165d13f Mon Sep 17 00:00:00 2001 > From: Patrick McHardy > Date: Sun, 8 Dec 2013 16:49:36 +0000 > Subject: [PATCH] netfilter: SYNPROXY target: restrict to INPUT/FORWARD > > Fix a crash in synproxy_send_tcp() when using the SYNPROXY target in the > PREROUTING chain caused by missing routing information. Applied, thanks Patrick!