From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: Re: [PATCH] netfilter: fix ordering of jumpstack allocation and table update Date: Fri, 18 Oct 2013 17:57:50 +0100 Message-ID: <20131018165749.GI3296@mudshark.cambridge.arm.com> References: <1382016273-21993-1-git-send-email-will.deacon@arm.com> <20131018111536.GA11132@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "netfilter-devel@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Paul E. McKenney" To: Pablo Neira Ayuso Return-path: Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:46055 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756688Ab3JRQ57 (ORCPT ); Fri, 18 Oct 2013 12:57:59 -0400 Content-Disposition: inline In-Reply-To: <20131018111536.GA11132@localhost> Sender: netfilter-devel-owner@vger.kernel.org List-ID: Hi Pablo, On Fri, Oct 18, 2013 at 12:15:36PM +0100, Pablo Neira Ayuso wrote: > On Thu, Oct 17, 2013 at 02:24:33PM +0100, Will Deacon wrote: > > During kernel stability testing on an SMP ARMv7 system, Yalin Wang > > reported the following panic from the netfilter code: [...] > > This patch adds an smp_wmb() before the assignment to table->private > > (which is essentially publishing newinfo) to ensure that all writes to > > newinfo will be observed before plugging it into the table structure. > > A dependent-read barrier is also added on the consumer side, to ensure > > the same ordering requirement are also respected there. > > We also need fixes for net/ipv6/netfilter/ip6_tables.c and > net/ipv4/netfilter/arp_tables.c as well. Could you extend this patch > and resend? Sure, I can try, but that's going to require a bit of time to sit down and look at the shared data, access order, dependencies etc. I'm currently preparing for Edinburgh, so it might be a while before I get a chance to extend this. Will