From patchwork Sat Feb 4 21:22:36 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Lu X-Patchwork-Id: 139591 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id B0E61B7237 for ; Sun, 5 Feb 2012 08:22:55 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753535Ab2BDVWv (ORCPT ); Sat, 4 Feb 2012 16:22:51 -0500 Received: from imr4.ericy.com ([198.24.6.9]:43656 "EHLO imr4.ericy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752956Ab2BDVWv (ORCPT ); Sat, 4 Feb 2012 16:22:51 -0500 Received: from eusaamw0707.eamcs.ericsson.se ([147.117.20.32]) by imr4.ericy.com (8.14.3/8.14.3/Debian-9.1ubuntu1) with ESMTP id q14LMj89020343; Sat, 4 Feb 2012 15:22:46 -0600 Received: from prattle.redback.com (147.117.20.214) by eusaamw0707.eamcs.ericsson.se (147.117.20.92) with Microsoft SMTP Server id 8.3.137.0; Sat, 4 Feb 2012 16:22:40 -0500 Received: from localhost (localhost [127.0.0.1]) by prattle.redback.com (Postfix) with ESMTP id 0D6B518A35E2; Sat, 4 Feb 2012 13:22:40 -0800 (PST) Received: from prattle.redback.com ([127.0.0.1]) by localhost (prattle [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 06242-06; Sat, 4 Feb 2012 13:22:39 -0800 (PST) Received: from localhost.localdomain (rbos-pc-12.lab.redback.com [10.12.11.132]) by prattle.redback.com (Postfix) with ESMTP id 9E2FB18A35E1; Sat, 4 Feb 2012 13:22:39 -0800 (PST) From: Shawn Lu To: eric.dumazet@gmail.com CC: davem@davemloft.net, netdev@vger.kernel.org, xiaoclu@gmail.com Subject: [PATCH] tcp_v4_send_reset: binding oif to iif in no sock case Date: Sat, 4 Feb 2012 13:22:36 -0800 Message-ID: <1328390556-14906-1-git-send-email-shawn.lu@ericsson.com> X-Mailer: git-send-email 1.7.0.4 In-Reply-To: References: MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Binding RST packet outgoing interface to incomming interface for tcp v4 when there is no socket associate with it. This has few benefits: 1. tcp_v6_send_reset already did that. 2. This helps tcp connect with SO_BINDTODEVICE set. When connection is lost, we still able to sending out RST using same interface. 3. we are send reply, it is most likely to be succeed if iif is used Signed-off-by: Shawn Lu --- V2: amend as Eric Dumazet suggested net/ipv4/tcp_ipv4.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 90e4793..f2fde8d 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -676,6 +676,12 @@ static void tcp_v4_send_reset(struct sock *sk, struct sk_buff *skb) arg.iov[0].iov_len, IPPROTO_TCP, 0); arg.csumoffset = offsetof(struct tcphdr, check) / 2; arg.flags = (sk && inet_sk(sk)->transparent) ? IP_REPLY_ARG_NOSRCCHECK : 0; + /* + * When socket is gone, all binding information is lost. + * routing might fail in this case. using iif for oif to + * make sure we can deliver it + */ + arg.bound_dev_if = sk ? sk->sk_bound_dev_if : inet_iif(skb); net = dev_net(skb_dst(skb)->dev); arg.tos = ip_hdr(skb)->tos;