Re: BUG: unable to handle kernel NULL pointer dereference in ipv6_select_ident

Eric Dumazet
2011-12-21T20:29:00Z

Le mercredi 21 décembre 2011 à 20:05 +0000, Chris Boot a écrit :
> On 21/12/2011 18:00, Eric Dumazet wrote:
> > Le mercredi 21 décembre 2011 à 18:36 +0100, Eric Dumazet a écrit :
> >
> >> Good point, thats a different problem then, since 3.1 is not supposed to
> >> have this bug.
> >>
> >> It seems rt->rt6i_peer points to invalid memory in your crash.
> >>
> >> (RBX=00000000000001f4)
> >>
> >> 8b 83 a4 00 00 00 mov 0xa4(%rbx),%eax p->refcnt
> >> 1f4+a4 -> CR2=0000000000000298
> >>
> > It would help if you can confirm latest linux tree can reproduce the
> > bug.
>
> Hi Eric,
>
> I just built a v3.2-rc6-140-gb9e26df with the same config as the Debian
> 3.1.0 kernel. I can reproduce the bug just as easily with this kernel as
> with the Debian kernel. Unfortunately I wasn't able to get an entire
> trace, for some reason it didn't appear to be printed to the serial port
> and hung after the (long) list of loaded kernel modules. The crash
> happens at the same offset:
>

Thanks !

Oh well, br_netfilter fake_rtable strikes again.

I'll cook a patch in a couple of minutes...