From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: RE: [PATCH] tcp: RST: binding oif to iif for tcp v4 Date: Sat, 04 Feb 2012 08:44:23 +0100 Message-ID: <1328341463.2480.12.camel@edumazet-laptop> References: <1328300212-18836-1-git-send-email-shawn.lu@ericsson.com> <1328304719.2480.5.camel@edumazet-laptop> <62162DF05402B341B3DB59932A1FA992B5B5C9FB94@EUSAACMS0702.eamcs.ericsson.se> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: "davem@davemloft.net" , "netdev@vger.kernel.org" , "xiaoclu@gmail.com" To: Shawn Lu Return-path: Received: from mail-ww0-f44.google.com ([74.125.82.44]:57255 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751845Ab2BDHo1 (ORCPT ); Sat, 4 Feb 2012 02:44:27 -0500 Received: by wgbdt10 with SMTP id dt10so4579022wgb.1 for ; Fri, 03 Feb 2012 23:44:26 -0800 (PST) In-Reply-To: <62162DF05402B341B3DB59932A1FA992B5B5C9FB94@EUSAACMS0702.eamcs.ericsson.se> Sender: netdev-owner@vger.kernel.org List-ID: Le vendredi 03 f=C3=A9vrier 2012 =C3=A0 16:43 -0500, Shawn Lu a =C3=A9c= rit : > See inline. > -----Original Message----- > From: Eric Dumazet [mailto:eric.dumazet@gmail.com]=20 > Le vendredi 03 f=C3=A9vrier 2012 =C3=A0 12:16 -0800, Shawn Lu a =C3=A9= crit : > > Binding RST packet outgoing interface to incomming interface for tc= p=20 > > v4. This has few benefits: > > 1. tcp_v6_send_reset already did that. >=20 > I dont think so. ipv6 makes no special provision for RST. > [shawn LU] it's in tcp_v6_send_response line 899 of tcp_ipv6.c > fl6.flowi6_oif =3D inet6_iif(skb); >=20 tcp_v6_send_response() is used to send RST _and_ ACK Its not reserved to RST. Thats why I said "no _special_ provision for RST" I repeat my question : Why do you believe only RST should be handled in a different manner tha= n other TCP messages ? If we decide to break asymmetric routing, we should do it completely an= d document it. It might already be broken for IPv6 and nobody cared / noticed.