Re: [kernel-hardening] Re: [RFC v1] mm: SLAB freelist randomization

[Thomas Garnier]

That's a use after free. The randomization of the freelist should not
have much effect on that. I was going to quote this exploit that is
applicable to SLAB as well:
https://jon.oberheide.org/blog/2010/09/10/linux-kernel-can-slub-overflow

Regards.
Thomas

On Thu, Apr 7, 2016 at 9:17 AM, Yves-Alexis Perez <corsac@xxxxxxxxxx> wrote:
> On mer., 2016-04-06 at 14:45 -0700, Kees Cook wrote:
>> > This security feature reduces the predictability of
>> > the kernel slab allocator against heap overflows.
>>
>> I would add "... rendering attacks much less stable." And if you can
>> find a specific example exploit that is foiled by this, I would refer
>> to it.
>
> One good example might (or might not) be the keyring issue from earlier this
> year (CVE-2016-0728):
>
> http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-ker
> nel-vulnerability-cve-2016-0728/
>
> Regards,
> --
> Yves-Alexis
>