Re: panic: mbuf too short for IPv6 header

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Sun, May 04, 2008 at 01:00:29PM +0200, Manuel Bouyer wrote:
> Hi,
> on a recent -current (kernel sources as of yesterday), I've got several
> panic: mbuf too short for IPv6 header
> 
> with the stack trace being:
> 0x0(0xf0c60500, 0x3a, 0x28, 0x169, 0xf2668dcc, 0x28) at 
> netbsd:icmp6_input+0x78
> icmp6_input(0xf0c60500, 0xf2668e70, 0x3a, 0xf2668e74, 0x6, 0x1) at 
> netbsd:ip6_input+0x8ec
> ip6_input(0x0, 0xe, 0x0, 0xf21474f0, 0x52e1474c, 0xf02ef580) at 
> netbsd:ip6intr+0x68
> ip6intr(0xf02ef400, 0xf2668edc, 0xf02ea400, 0x10, 0x44, 0x0) at 
> netbsd:softint_thread+0x90
> softint_thread(0xf212d170, 0xf2147980, 0xf02a8ac0, 0x0, 0x904010e1, 
> 0x90401fe1) at netbsd:lwp_trampoline+0x8
> End traceback...
> 
> I think it's related to running named on this box. Without named running,
> the box had been up for several hours; with named the panic occurs in less
> than one hour (tried 3 times).
> 
> Looking at the mail archives, it seems this issue has already been reported,
> but I didn't find a definitive fix. The attached patch mimics code in
> ipv4 icmp_input, and makes sure the related mbuf part is contigous and
> writeable. With this patch, the box has been up for 13 hours with named
> running, without problems. Does it look right ?

FYI, I commited this patch. I've been running with it for 3 days, without
apparent problems.

-- 
Manuel Bouyer, LIP6, Universite Paris VI.           
Manuel.Bouyer%lip6.fr@localhost
     NetBSD: 26 ans d'experience feront toujours la difference
--