Re: A commit between 2.6.16.4 and 2.6.16.5 failed crashme

["Zhao Forrest" <forrest.zhao@gmail.com>]

On 11/29/06, Adrian Bunk <bunk@stusta.de> wrote:
> On Wed, Nov 29, 2006 at 12:18:18AM -0800, Zhao Forrest wrote:
> > On 11/28/06, Andi Kleen <ak@suse.de> wrote:
> > >
> > >> I first need to contact the author of test case if we could send the
> > >> test case to open source. The test case is called "crashme",
> > >
> > >Is that the classical crashme as found in LTP or an enhanced one?
> > >Do you run it in a special way? Is the crash reproducible?
> > >
> > >We normally run crashme regularly as part of LTP, Cerberus etc.
> > >so at least any obvious bugs should in theory be caught.
> > >
> >
> > Let me change the subject of this thread.
> > I just read our private version of crashme. It's based on crashme
> > version 2.4 and add some logging capability, no other enhancement. So
> > it should be the same as crashme in LTP.
> >
> > It is solidly reproducible within 3 minutes of running crashme.
> >
> > The current status is: we know it's a commit between 2.6.16.4 and
> > 2.6.16.5 that introduce this bug.
> >
> > Our network is very slow(only 5-6K/second). So we'll start the
> > git-bisect tomorrow after finishing downloading the 2.6.16 stable git
> > tree.
>
> Thanks for your report.
>
> A git-bisect might be a bit of overkill considering that there were only
> two patches applied beween 2.6.16.4 and 2.6.16.5:
>
> Andi Kleen (2):
>       x86_64: Clean up execve
>       x86_64: When user could have changed RIP always force IRET (CVE-2006-0744)
>
> I've attached both patches.
>
> Could you manually bisect first applying "x86_64: Clean up execve"
> (patch-2.6.16.4-5-1) against 2.6.16.4?
>

Hi Adrian

It's the second patch(x86_64: When user could have changed RIP always
force IRET (CVE-2006-0744)) that trigger this bug.
We have run crashme on a IBM server with 2 Intel dual-core CPU, a SUN
server with 2 AMD Opteron single-core CPU and a SUN server with 8 AMD
Opteron dual-core CPU.
Running crashme can trigger kernel panic on all platforms after the
second patch is applied to 2.6.16.4. And when kernel panic happens,
there's only "Kernel panic - not syncing: Attempted to kill init" on
the screen.

Please let me know if you need any further information.

Thanks,
Forrest