Re: NULL pointer dereference in selinux_ip_postroute_compat

On Tue, Aug 7, 2012 at 5:58 PM, John Stultz [off-list ref] wrote:

On 08/07/2012 02:50 PM, Paul Moore wrote:

quoted

On Tue, Aug 7, 2012 at 2:12 PM, John Stultz [off-list ref]
wrote:

quoted

Hi,
     With my kvm environment using 3.6-rc1+, I'm seeing NULL pointer
dereferences in selinux_ip_postroute_compat(). It looks like the sksec
value
is null and we die in the following line:

     if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))

This triggers every time I shutdown the machine, but has also triggered
randomly after a few hours.

This is on an ubuntu 12.04 image, not using selinux.

NOTE: Adding the SELinux list to the CC line

Thanks!

quoted

Hi,

I'm trying to understand this and I was hoping you could you clarify a
few things for me:

* Is the panic in the Ubuntu 12.04 guest, or the host?  If the host,
could you share what distribution you are using?

Sorry, its a 12.04 guest.  I think the host is Ubuntu 12.04 as well.

quoted

* When you say you are not using SELinux, could you be more specific?
It seems odd that you are not using SELinux but the panic is happening
in a SELinux hook.

I just mean that, being Ubuntu,  the system (userland) isn't configured to
use selinux.  SELinux is just enabled in the kernel config.

Thanks for the quick response, I'll setup an Ubuntu guest and see if I
can reproduce this ... something is odd.  Anything non-standard about
your guest install or anything else you think might be helpful?

-- 
paul moore
www.paul-moore.com