Re: i686 quirk for AMD Geode

Willy Tarreau
2009-11-11T06:36:25Z

On Tue, Nov 10, 2009 at 10:15:58PM -0800, H. Peter Anvin wrote:
> On 11/10/2009 09:52 PM, Willy Tarreau wrote:
> >
> > - last, the probability of having an NX page just after an
> > executable one seems too tight to me to even constitute
> > an attack vector ! BTW, I'm not even certain that all CPUs
> > correctly implement this check !
> >
>
> Do you have *any* *evidence* *whatsoever* for that assertion?!

No, just basic feeling based on implementation cost and difficulty
vs gains as I explained.

> I personally will consider something that doesn't implement proper
> security check to be a potential security hole and will NAK the patch.

Even in the case of the NOPL instruction ? I clearly don't see
the potential security hole !

Willy