From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264095AbUBOEWM (ORCPT ); Sat, 14 Feb 2004 23:22:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264113AbUBOEWL (ORCPT ); Sat, 14 Feb 2004 23:22:11 -0500 Received: from [193.226.51.42] ([193.226.51.42]:15119 "HELO al.math.unibuc.ro") by vger.kernel.org with SMTP id S264095AbUBOEWJ (ORCPT ); Sat, 14 Feb 2004 23:22:09 -0500 Message-ID: <402EF3E9.4090502@al.math.unibuc.ro> Date: Sun, 15 Feb 2004 06:22:01 +0200 From: Mihai Tanasescu User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: linux-kernel@vger.kernel.org Subject: Kernel 2.4.24 bug Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, I've recently discovered a bug in the conntrack system I think of the linux 2.4.24 kernel: I have the following setup: eth0 Link encap:Ethernet HWaddr 00:40:F4:79:11:A3 inet addr:213.154.157.242 Bcast:213.154.157.243 \ eth0:0 Link encap:Ethernet HWaddr 00:40:F4:79:11:A3 inet addr:213.154.157.42 Bcast:213.154.157.47 \ eth0:1 Link encap:Ethernet HWaddr 00:40:F4:79:11:A3 inet addr:213.154.157.43 Bcast:213.154.157.47 \ eth0:2 Link encap:Ethernet HWaddr 00:40:F4:79:11:A3 inet addr:213.154.157.44 Bcast:213.154.157.47 \ eth0:3 Link encap:Ethernet HWaddr 00:40:F4:79:11:A3 inet addr:213.154.157.45 Bcast:213.154.157.47 \ and I have something like SNAT 192.168.40.10,192.168.40.11 to 213.154.157.242 SNAT 192.168.40.12,192.168.40.13 to 213.154.157.42 and so on for every alias IP on my external interface eth0 with the 2.4.24 kernel NAT was only working for the first ip of the network interface=213.154.157.242 in my case (for the other ones=the aliases it reacted in the following way .... for example an icmp ping from 192.168.40.13 to some site would get seen with tcpdump exiting the server with the correct nated IP ...I would see it come back on the external interface..but no packet would come out the internal interface in order to reach the private ip that originally sent the ping ..) like: tcpdump -n -i eth1 icmp echo request 192.168.40.13 > 194.102.255.2 tcpdump -n -i eth0 icmp echo request 213.154.157.42 > 194.102.255.2 icmp echo reply 194.102.255.2 > 213.154.157.42 but I get NO reply like this going to the private/lan station tcpdump -n -i eth1 icmp echo reply 194.102.255.2 > 192.168.40.13 (it seems the packet gets stuck in the router and doesn't reach the local station that send the initial packet)