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Date: Wed, 10 Nov 2010 22:56:58 -0800
From: Kees Cook <kees.cook@canonical.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: matthieu castet <castet.matthieu@free.fr>,
        Siarhei Liakh <sliakh.lkml@gmail.com>,
        Rusty Russell <rusty@rustcorp.com.au>, linux-kernel@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "H. Peter Anvin" <hpa@zytor.com>, Thomas Gleixner <tglx@linutronix.de>,
        Arjan van de Ven <arjan@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [Security] proactive defense: using read-only memory, RO/NX
 modules
Message-ID: <20101111065658.GA5876@outflux.net>
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 <20101110090415.GC8370@elte.hu>
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Hi Ingo,

On Wed, Nov 10, 2010 at 10:04:15AM +0100, Ingo Molnar wrote:
> * Kees Cook <kees.cook@canonical.com> wrote:
> > Oh, well, yes, that's a good reason. :) Where was this covered? I'd like to help 
> > get it reproduced and ironed out.
> 
> Matthieu Castet seems to have dusted off those patches and submitted two of them in 
> this mail:
> 
>   Subject: [RFC] reworked NX protection for kernel data
> 
> Matthieu, are you still interested in this topic?
> 
> The original, broken patches were these -tip commits:
> 
>  1e858c081af5: x86, mm: RO/NX protection for loadable kernel modules
>  18c60ddc9eff: x86, mm: NX protection for kernel data
>  c226a2feba21: x86, mm: Set first MB as RW+NX
>  b29d530510d4: x86, mm: Correcting improper large page preservation
> 
> I reported one of the crashes in:
> 
>   Subject: Re: [tip:x86/mm] x86, mm: Set first MB as RW+NX
> 
> on lkml.

Thanks for looking this up!

Can we get 1e858c081af5 and 18c60ddc9eff back in, and then work forward
from there?

-Kees

-- 
Kees Cook
Ubuntu Security Team