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_PATCH,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 89680C43460 for ; Thu, 8 Apr 2021 09:05:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4BA016044F for ; Thu, 8 Apr 2021 09:05:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230342AbhDHJFM (ORCPT ); Thu, 8 Apr 2021 05:05:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230337AbhDHJFM (ORCPT ); Thu, 8 Apr 2021 05:05:12 -0400 Received: from Chamillionaire.breakpoint.cc (Chamillionaire.breakpoint.cc [IPv6:2a0a:51c0:0:12e:520::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CB00C061761 for ; Thu, 8 Apr 2021 02:05:01 -0700 (PDT) Received: from fw by Chamillionaire.breakpoint.cc with local (Exim 4.92) (envelope-from ) id 1lUQax-0005sY-EH; Thu, 08 Apr 2021 11:04:59 +0200 Date: Thu, 8 Apr 2021 11:04:59 +0200 From: Florian Westphal To: Ali Abdallah Cc: netfilter-devel@vger.kernel.org Subject: Re: [PATCH] conntrack_tcp: Reset the max ACK flag on SYN in ignore state Message-ID: <20210408090459.GQ13699@breakpoint.cc> References: <20210408061203.35kbl44elgz4resh@Fryzen495> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210408061203.35kbl44elgz4resh@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 ignore state, we let SYN goes in original, the server might respond > with RST/ACK, and that RST packet is erroneously dropped because of the > flag IP_CT_TCP_FLAG_MAXACK_SET being already set. > --- > net/netfilter/nf_conntrack_proto_tcp.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c > index ec23330687a5..891a66e35afd 100644 > --- a/net/netfilter/nf_conntrack_proto_tcp.c > +++ b/net/netfilter/nf_conntrack_proto_tcp.c > @@ -963,6 +963,9 @@ int nf_conntrack_tcp_packet(struct nf_conn *ct, > > ct->proto.tcp.last_flags = > ct->proto.tcp.last_wscale = 0; > + /* Reset the max ack flag so in case the server replies > + * with RST/ACK it will be marked as an invalid rst */ "not be marked"? > + ct->proto.tcp.seen[dir].flags &= ~IP_CT_TCP_FLAG_MAXACK_SET; > tcp_options(skb, dataoff, th, &seen); > if (seen.flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {