From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: Re: [conntrackd] allowing DisableExternalCache in alarm mode Date: Tue, 1 Sep 2015 18:44:21 +0200 Message-ID: <20150901164421.GA3320@salvia> References: <20150828164912.GD3436@salvia> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Netfilter Development Mailing list To: Arturo Borrero Gonzalez Return-path: Received: from mail.us.es ([193.147.175.20]:54603 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753126AbbIAQhw (ORCPT ); Tue, 1 Sep 2015 12:37:52 -0400 Content-Disposition: inline In-Reply-To: Sender: netfilter-devel-owner@vger.kernel.org List-ID: On Mon, Aug 31, 2015 at 09:55:23AM +0200, Arturo Borrero Gonzalez wrote: > On 28 August 2015 at 18:49, Pablo Neira Ayuso wrote: > > > > Are these FTP data flows? I'm asking this because the master > > connection (control flow) may be missing in the conntrack table, thus > > the ENOENT error. > > Makes sense. > > Would you consider accepting the patch? I think you can fix the problem that you're noticing by extending timer_add(). Note that the general idea behind the alarm approach is to insert a timer with a random time wait in unit from 0..M seconds. A quick workaround to address this is that master conntracks are placed in the time range from 0..N/2, then you place non-master conntrack entries in the range from N/2+1 to M. Then, unless there is packet loss, most likely the expected conntrack will find the master one. It should be just a few more extra lines away from this oneliner.