From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A0B8C433ED for ; Wed, 28 Apr 2021 13:23:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F08D161151 for ; Wed, 28 Apr 2021 13:23:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239770AbhD1NYZ (ORCPT ); Wed, 28 Apr 2021 09:24:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239634AbhD1NYZ (ORCPT ); Wed, 28 Apr 2021 09:24:25 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F805C061574 for ; Wed, 28 Apr 2021 06:23:40 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1lbkAE-0004Tm-CG; Wed, 28 Apr 2021 15:23:38 +0200 Date: Wed, 28 Apr 2021 15:23:38 +0200 From: Florian Westphal To: Ali Abdallah Cc: netfilter-devel@vger.kernel.org Subject: Re: [PATCH] Avoid potentially erroneos RST check Message-ID: <20210428132338.GF975@breakpoint.cc> References: <20210428131147.w2ppmrt6hpcjin5i@Fryzen495> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210428131147.w2ppmrt6hpcjin5i@Fryzen495> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org Ali Abdallah wrote: > In 'commit b303e7b80ff1 ("Reset the max ACK flag on SYN in ignore state")' > we reset the max ACK number to avoid dropping valid RST that is a > response to a SYN. > > Unfortunately that might not be enough, an out of order ACK in origin > might reset it back, and we might end up again dropping valid RST. > > This patch disables the RST check when we are not in established state > and we receive an RST with SEQ=0 that is most likely a response to a > SYN we had let it go through. > > Signed-off-by: Ali Abdallah Looks good, thanks! Acked-by: Florian Westphal