Re: [PATCH 2.6.28] tcp_ipv6: fix use of uninitialized memory

[Ingo Molnar <mingo@elte.hu>]

* David Miller <davem@davemloft.net> wrote:

> From: Arnaldo Carvalho de Melo <acme@redhat.com>
> Date: Fri, 12 Sep 2008 09:44:05 -0300
> 
> > Em Fri, Sep 12, 2008 at 09:05:25AM +0200, Vegard Nossum escreveu:
> > > >From 6544c4074aa5dde2e3f4d3e02f5601c1c33b770e Mon Sep 17 00:00:00 2001
> > > From: Vegard Nossum <vegard.nossum@gmail.com>
> > > Date: Tue, 9 Sep 2008 07:17:32 +0200
> > > Subject: [PATCH] tcp_ipv6: fix use of uninitialized memory
> > > 
> > > inet6_rsk() is called on a struct request_sock * before we
> > > have checked whether the socket is an ipv6 socket or a ipv6-
> > > mapped ipv4 socket. The access that triggers this is the
> > > inet_rsk(rsk)->inet6_rsk_offset dereference in inet6_rsk().
> > > 
> > > This is arguably not a critical error as the inet6_rsk_offset
> > > is only used to compute a pointer which is never really used
> > > (in the code path in question) anyway. But it might be a
> > > latent error, so let's fix it.
> > > 
> > > Spotted by kmemcheck.
> > 
> > Humm, so this was poisoned at allocation and then when inet6_rsk_offset
> > was accessed it noticed, interesting, thanks!
> > 
> > Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
> 
> Good find :)  I'll add this to net-next-2.6, thanks!

nice - i think kmemcheck is starting to build up a healthy list of 
references :-)

	Ingo