From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH net] tcp/dccp: fix lockdep issue when SYN is backlogged Date: Tue, 2 Oct 2018 11:25:37 -0700 Message-ID: References: <20181001220226.252453-1-edumazet@google.com> <20181001.154308.1092275550794942572.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, eric.dumazet@gmail.com To: David Miller , edumazet@google.com Return-path: Received: from mail-pg1-f194.google.com ([209.85.215.194]:41023 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725951AbeJCBKV (ORCPT ); Tue, 2 Oct 2018 21:10:21 -0400 Received: by mail-pg1-f194.google.com with SMTP id 23-v6so337559pgc.8 for ; Tue, 02 Oct 2018 11:25:40 -0700 (PDT) In-Reply-To: <20181001.154308.1092275550794942572.davem@davemloft.net> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 10/01/2018 03:43 PM, David Miller wrote: > From: Eric Dumazet > Date: Mon, 1 Oct 2018 15:02:26 -0700 >> This patch extends what I did in commit 449809a66c1d ("tcp/dccp: >> block BH for SYN processing") by adding an extra rcu_read_{lock|unlock} >> pair in the paths that might be taken when processing SYN from >> socket backlog (thus possibly in process context) >> >> Fixes: 06f877d613be ("tcp/dccp: fix other lockdep splats accessing ireq_opt") >> Signed-off-by: Eric Dumazet >> Reported-by: syzbot > > Applied and queued up for -stable, thanks Eric. > This needs a followup, timers do not imply rcu_read_lock() :/ I will send a patch, sorry for not having caught this earlier.