From owner-freebsd-stable@FreeBSD.ORG Fri Jul 11 09:25:55 2014 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id F3AE3F63 for ; Fri, 11 Jul 2014 09:25:54 +0000 (UTC) Received: from mail-qg0-x22a.google.com (mail-qg0-x22a.google.com [IPv6:2607:f8b0:400d:c04::22a]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id AA1ED236C for ; Fri, 11 Jul 2014 09:25:53 +0000 (UTC) Received: by mail-qg0-f42.google.com with SMTP id e89so718997qgf.1 for ; Fri, 11 Jul 2014 02:25:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=packetdam.com; s=google; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type; bh=CmsVuccvpx31zcWrfI+O+eB8X5EJ9PAaoRqx5g6xf3s=; b=RIcKGPwrIvVeIRa07DkoWavpPdwQFV5YwcpItLciQrGIV9DBbV8xkHN3d6pQlCX6aF y5ulRvvGO8suBTf+3Stv5lw+gHUh3BIeE2Q7cvFehePjhOKrQhlpyIeKJUCLEkcMxRW9 Xh8UDyHELJAg2yFlJrxKQ0ABBKlD3H0+xpR2o= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:content-type; bh=CmsVuccvpx31zcWrfI+O+eB8X5EJ9PAaoRqx5g6xf3s=; b=UZ3HRMhRpMn+4WW+U9gBuxpwIi4PXFvuY53E1hh7FO2OtaCxT5R3LH4/9DOQkJbJOv hgk5IEam2CTUPYu+cs2/Y9kxaO2i1Zu9ersEZ7duv6sk2vrf+cA8IWol0lMLVl6R8wfx wUrSwEMwAqnf9wOfKGxtUFH8ztxBVvUl5DbPN/ObGCD4HQATqc1gvIp0WYwmD6IUgL1t eXthIbrdksGzqXRWL6DVqWGqinQJ/z2tpVVXvDz35jWxK7R+3MR9g7JRhj+u6few+1d5 ePe4yiM38SpFSXkfHuSGS0P6bvyTr8gHPX6deJaUdVQ57dURHLXDSsZBHlcFOr3pBHLl bfUQ== X-Gm-Message-State: ALoCoQmFoPb1EE8bS7b0Dia9oO8NfY5NoBo2abHesZIIyS/7NLzIbv8upOErlMZEOiZ52jRrkDav X-Received: by 10.140.50.50 with SMTP id r47mr68331555qga.96.1405070753002; Fri, 11 Jul 2014 02:25:53 -0700 (PDT) MIME-Version: 1.0 Received: by 10.229.185.6 with HTTP; Fri, 11 Jul 2014 02:25:12 -0700 (PDT) X-Originating-IP: [195.59.118.200] In-Reply-To: <20140711014459.GA79102@anubis.morrow.me.uk> References: <201407091402.23537.jhb@freebsd.org> <201407101430.52616.jhb@freebsd.org> <20140711014459.GA79102@anubis.morrow.me.uk> From: Vlad Galu Date: Fri, 11 Jul 2014 10:25:12 +0100 Message-ID: Subject: Re: Weird ISR accounting in 10-STABLE To: freebsd-stable@freebsd.org, ben@morrow.me.uk Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18 X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 11 Jul 2014 09:25:55 -0000 What intrigues me is the reject flag not being honoured. The loopback traffic was looping. On Fri, Jul 11, 2014 at 2:45 AM, Ben Morrow wrote: > Quoth Vlad Galu : > > On Thu, Jul 10, 2014 at 9:56 PM, Vlad Galu wrote: > > > > > > Good catch, why didn't I think of that earlier! I can see a lot of IPv6 > > > traffic that I can't really explain. Since I was running pf with > synproxy I > > > disabled pf altogether, but that did not improve things. Here is a > snapshot > > > (source IP address edited): > > > > > > -- cut here -- > > > 22:52:40.195950 IP6 A:B:C:D:E::1000.62571 > ::10.31.31.153.12132: Flags > > The second address here is an 'IPv4-compatible IPv6 address', which are > not these days considered to be useful. See RFC 4291 section 2.5.5.1. > > I suspect the process which owns A:B:C:D:E::1000.62571 is playing silly > games of some sort; possibly it's making Linux-based assumptions about > the behaviour of dual-stack hosts which don't apply on BSD. > > > It was a routing loop! I kept seeing lots of identical SYN packets. I > > somehow ended up with this v6 table entry: > > -- cut here -- > > Routing tables > > > > Internet6: > > > > Destination Gateway Flags > > Netif Expire > > > > ::/96 ::1 UGRS > > lo0 > > This is a correct route, and will not cause a routing loop. It's also > *not* the same as the IPv6 loopback route (as someone else said); that > route looks like > > ::1 link#2 UH lo0 > > and should also be present (the link number might be different, > obviously). > > The 'R' flag means 'reject': because these addresses are not useful, > there should be a routing table entry to ensure packets addressed to > them get thrown away rather than sent out on the wire. You need to find > out why they are being generated in the first place. > > Ben > > -- Regards, Vlad