From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [PATCH] death_by_event() does not check IPS_DYING_BIT - race condition against ctnetlink_del_conntrack Date: Thu, 30 Aug 2012 20:39:50 +0200 Message-ID: <20120830183950.GB13190@1984> References: <7353554.n89QJXU3eh@gentoovm> <149613366.axl8ME3any@gentoovm> <20120830162248.GA3783@1984> <10622350.k1HJ7t2ROS@gentoovm> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netfilter-devel@vger.kernel.org To: Oliver Return-path: Received: from mail.us.es ([193.147.175.20]:34720 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753247Ab2H3Sj4 (ORCPT ); Thu, 30 Aug 2012 14:39:56 -0400 Content-Disposition: inline In-Reply-To: <10622350.k1HJ7t2ROS@gentoovm> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Thu, Aug 30, 2012 at 07:49:24PM +0200, Oliver wrote: > On Thursday 30 August 2012 18:22:48 you wrote: > > Unfortunately, asymmetric active-active is a crazy setup for conntrack > > (documentation already discuss this). The state synchronization that > > we are doing is asynchronous, so state-updates race with TCP packet. > > We don't support this, sorry. > > The environment does fulfil the assumptions necessary for replication to happen > within the handshake so under 3.2 there is no issue with handshakes completing > under an asymmetric path. Interesting, how are those assumptions fulfilled? > Nonetheless, what doesn't make sense is that this operates under 3.2 and not > 3.4 - also is the fact that having a "-j CT --notrack" on specific traffic (i.e. > asymmetric should not matter because there is no stateful tracking) Agreed. But I don't come with any netfilter change that may result in that problem you're reporting. You'll have to debug this and get back to me with more information.