From owner-freebsd-hackers@FreeBSD.ORG Sat Aug 22 06:09:49 2009 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5DDEE106564A; Sat, 22 Aug 2009 06:09:49 +0000 (UTC) (envelope-from prvs=147868619d=brian@Awfulhak.org) Received: from idcmail-mo2no.shaw.ca (idcmail-mo2no.shaw.ca [64.59.134.9]) by mx1.freebsd.org (Postfix) with ESMTP id 1354F8FC1A; Sat, 22 Aug 2009 06:09:48 +0000 (UTC) Received: from pd7ml2no-ssvc.prod.shaw.ca ([10.0.153.162]) by pd5mo1no-svcs.prod.shaw.ca with ESMTP; 21 Aug 2009 23:41:40 -0600 X-Cloudmark-SP-Filtered: true X-Cloudmark-SP-Result: v=1.0 c=1 a=BN5Fd0iOSU8A:10 a=MJPcHhXccCG8eBs0us8XwA==:17 a=6I5d2MoRAAAA:8 a=MMwg4So0AAAA:8 a=g6kdJJKMxq21qQ3NCfAA:9 a=5kP0PoyluC1s4KTuiH4A:7 a=HKIDxmP8TC9LG-Yg7iNi9MoiEDkA:4 a=SV7veod9ZcQA:10 a=WJ3hkfHDukgA:10 a=0dbfaRH7gSmKxhbu:21 a=N9QTdzOVIOTVbCiS:21 Received: from unknown (HELO store.lan.Awfulhak.org) ([70.79.162.198]) by pd7ml2no-dmz.prod.shaw.ca with ESMTP; 21 Aug 2009 23:41:40 -0600 Received: from store.lan.Awfulhak.org (localhost.localdomain [127.0.0.1]) by localhost (Email Security Appliance) with SMTP id 7DCDCC433B6_A8F8510B; Sat, 22 Aug 2009 05:41:36 +0000 (GMT) Received: from gw.Awfulhak.org (gw.lan.Awfulhak.org [172.16.0.1]) by store.lan.Awfulhak.org (Sophos Email Appliance) with ESMTP id 11D66C460F8_A8F850CF; Sat, 22 Aug 2009 05:41:32 +0000 (GMT) Received: from dev.lan.Awfulhak.org (brian@dev.lan.Awfulhak.org [172.16.0.5]) by gw.Awfulhak.org (8.14.3/8.14.3) with ESMTP id n7M5fYmq092308; Fri, 21 Aug 2009 22:41:34 -0700 (PDT) (envelope-from brian@Awfulhak.org) Date: Fri, 21 Aug 2009 22:41:34 -0700 From: Brian Somers To: Kip Macy Message-ID: <20090821224134.11d9a2a1@dev.lan.Awfulhak.org> In-Reply-To: <20090821215503.3eec9a15@dev.lan.Awfulhak.org> References: <20090821164312.641fe2bd@dev.lan.Awfulhak.org> <3c1674c90908211713j36415b96q58b0ed66cc82713f@mail.gmail.com> <20090821215503.3eec9a15@dev.lan.Awfulhak.org> X-Mailer: Claws Mail 3.7.2 (GTK+ 2.16.5; i386-portbld-freebsd8.0) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Mailman-Approved-At: Sat, 22 Aug 2009 13:43:37 +0000 Cc: freebsd-hackers@FreeBSD.org, Brian Somers Subject: Re: kernel panics in in_lltable_lookup (with INVARIANTS) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 22 Aug 2009 06:09:49 -0000 On Fri, 21 Aug 2009 21:55:03 -0700 Brian Somers wrote: > On Fri, 21 Aug 2009 17:13:45 -0700 Kip Macy wrote: > > Try this: > >=20 > > Index: sys/net/flowtable.c > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > --- sys/net/flowtable.c (revision 196382) > > +++ sys/net/flowtable.c (working copy) > > @@ -688,6 +688,12 @@ > > struct rtentry *rt =3D ro->ro_rt; > > struct ifnet *ifp =3D rt->rt_ifp; > >=20 > > + if (ifp->if_flags & IFF_POINTOPOINT) { > > + RTFREE(rt); > > + ro->ro_rt =3D NULL; > > + return (ENOENT); > > + } > > + > > if (rt->rt_flags & RTF_GATEWAY) > > l3addr =3D rt->rt_gateway; > > else > >=20 > > You'll need to apply this by hand as gmail munges the formatting. > >=20 > > -Kip >=20 > Hi, >=20 > That certainly stops the panic, however data routed to the tun > interface doesn't come out the back end and data written > to the back end doesn't come out the tun interface. [.....] > Maybe this problem isn't a routing problem. I'll > look into it further and figure out if the packet is getting to the tun > driver and if so, what it thinks it's doing with it. I wasn't correct - the data *IS* being read out of the back of the tunnel device. When I send the ICMP, it goes into the tun device and comes out the back end as an AF_LINK packet. ppp silently discards this (ironically I have a comment noting that I should really track unidentified packet counts). I'll try to figure out what in if_tun.c is corrupting the family next... Cheers. > > On Fri, Aug 21, 2009 at 16:43, Brian Somers wrote: > > > Hi, > > > > > > I've been working on a fix to address an issue that came up with > > > our update of openssh-5. =C2=A0The issue is that openssh-5 now uses > > > pipe() to create stdin/stdout channels between sshd and the server > > > side program where it used to use socketpair(). =C2=A0Because it uses > > > pipe(), stdin is no longer bi-directional and cannot be used for both > > > input and output by a child process. =C2=A0This breaks the use of ssh > > > as a tunnel with ppp on either end (set device "!ssh -e none host > > > ppp -direct label") > > > > > > I talked with des@ for a while and then with the openssh folks and > > > have not been able to resolve the issues in openssh that made them > > > choose to enforce the use of pipe() over socketpair(). =C2=A0I now ha= ve a > > > patch to ppp that makes ppp detect that it's connected via pipe() and > > > causes it to use stdin for input and stdout for output (usually it ex= pects > > > just one descriptor). =C2=A0Although I'm happy with the patch and pla= nned on > > > requesting permission to commit, I've bumped into a show-stopper > > > that seems unrelated, so I thought I'd ask here if anyone has seen > > > this or has any suggestions as to what the problem might be. > > > > > > The issue.... > > > > > > I'm seeing a panic when I send traffic through a ppp link: > > > > > > panic string is: sin_family 18 > > > Stack trace starts: > > > =C2=A0 =C2=A0in_lltable_lookup() > > > =C2=A0 =C2=A0llentry_update() > > > =C2=A0 =C2=A0flowtable_lookup() > > > =C2=A0 =C2=A0ip_output() > > > =C2=A0 =C2=A0.... > > > > > > The panic is due to a KASSERT in in_lltable_lookup() that expects the > > > sockaddr to be AF_INET. =C2=A0Number 18 is AF_LINK. > > > > > > AFAICT this is happening while setting up a temporary route for the > > > first outbound packet. =C2=A0I haven't been able to do much investiga= tion > > > yet due to other patches in my tree that seem to have broken all my > > > kernel symbols, but once I get a clean rebuild I should be back in > > > business. > > > > > > If anyone has any suggestions, I'm all ears! > > > > > > Cheers. --=20 Brian Somers Don't _EVER_ lose your sense of humour !