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From: Kees Cook <keescook@chromium.org>
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Subject: Re: [PATCH v2 01/11] mm: Implement stack frame object validation
To: Andy Lutomirski <luto@amacapital.net>
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On Wed, Jul 13, 2016 at 3:01 PM, Andy Lutomirski <luto@amacapital.net> wrote:
> On Wed, Jul 13, 2016 at 2:55 PM, Kees Cook <keescook@chromium.org> wrote:
>> This creates per-architecture function arch_within_stack_frames() that
>> should validate if a given object is contained by a kernel stack frame.
>> Initial implementation is on x86.
>>
>> This is based on code from PaX.
>>
>
> This, along with Josh's livepatch work, are two examples of unwinders
> that matter for correctness instead of just debugging.  ISTM this
> should just use Josh's code directly once it's been written.

Do you have URL for Josh's code? I'd love to see what happening there.

In the meantime, usercopy can use this...

-Kees

-- 
Kees Cook
Chrome OS & Brillo Security