From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH V2] sctp: reset flowi4_oif parameter on route lookup Date: Fri, 25 Apr 2014 09:45:03 -0400 Message-ID: <535A66DF.7080207@gmail.com> References: <1398416141-18916-1-git-send-email-xufeng.zhang@windriver.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-sctp@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org To: Xufeng Zhang , nhorman@tuxdriver.com, davem@davemloft.net, ja@ssi.bg Return-path: In-Reply-To: <1398416141-18916-1-git-send-email-xufeng.zhang@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 04/25/2014 04:55 AM, Xufeng Zhang wrote: > 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 -vlad