From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753505AbaFGBoK (ORCPT ); Fri, 6 Jun 2014 21:44:10 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35979 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752553AbaFGBXg (ORCPT ); Fri, 6 Jun 2014 21:23:36 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "David S. Miller" , "Julian Anastasov" , "Vlad Yasevich" , "Xufeng Zhang" Date: Sat, 07 Jun 2014 02:26:28 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 17/92] sctp: reset flowi4_oif parameter on route lookup In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.60-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Xufeng Zhang [ Upstream commit 85350871317a5adb35519d9dc6fc9e80809d42ad ] commit 813b3b5db83 (ipv4: Use caller's on-stack flowi as-is in output route lookups.) introduces another regression which is very similar to the problem of commit e6b45241c (ipv4: reset flowi parameters on route connect) wants to fix: Before we call ip_route_output_key() in sctp_v4_get_dst() to get a dst that matches a bind address as the source address, we have already called this function previously and the flowi parameters have been initialized including flowi4_oif, so when we call this function again, the process in __ip_route_output_key() will be different because of the setting of flowi4_oif, and we'll get a networking device which corresponds to the inputted flowi4_oif as the output device, this is wrong because we'll never hit this place if the previously returned source address of dst match one of the bound addresses. To reproduce this problem, a vlan setting is enough: # ifconfig eth0 up # route del default # vconfig add eth0 2 # vconfig add eth0 3 # ifconfig eth0.2 10.0.1.14 netmask 255.255.255.0 # route add default gw 10.0.1.254 dev eth0.2 # ifconfig eth0.3 10.0.0.14 netmask 255.255.255.0 # ip rule add from 10.0.0.14 table 4 # ip route add table 4 default via 10.0.0.254 src 10.0.0.14 dev eth0.3 # sctp_darn -H 10.0.0.14 -P 36422 -h 10.1.4.134 -p 36422 -s -I You'll detect that all the flow are routed to eth0.2(10.0.1.254). Signed-off-by: Xufeng Zhang Signed-off-by: Julian Anastasov Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/sctp/protocol.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 6f6ad86..de35e01 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -528,8 +528,13 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr, continue; if ((laddr->state == SCTP_ADDR_SRC) && (AF_INET == laddr->a.sa.sa_family)) { - fl4->saddr = laddr->a.v4.sin_addr.s_addr; fl4->fl4_sport = laddr->a.v4.sin_port; + flowi4_update_output(fl4, + asoc->base.sk->sk_bound_dev_if, + RT_CONN_FLAGS(asoc->base.sk), + daddr->v4.sin_addr.s_addr, + laddr->a.v4.sin_addr.s_addr); + rt = ip_route_output_key(&init_net, fl4); if (!IS_ERR(rt)) { dst = &rt->dst;