Re: [PATCH] ppp: mppe: Remove VLA usage

[Kees Cook]

On Mon, Jul 16, 2018 at 4:01 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> On Mon, Jul 16, 2018 at 6:05 AM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>> In the quest to remove all stack VLA usage from the kernel[1], this
>> removes the discouraged use of AHASH_REQUEST_ON_STACK (and associated
>> VLA) by switching to shash directly and keeping the associated descriptor
>> allocated with the regular state on the heap.
>>
>> [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@xxxxxxxxxxxxxx
>>
>> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
>
> I had concerns at first that this approach might make it slower, but
> upon reading through implementation of the shash_ahash_ implementation,
> I concluded that it can only be better than before, improving both
> performance and stack usage.
>
> Acked-by: Arnd Bergmann <arnd@xxxxxxxx>

Paul,

Is this something you can take via your tree?

Thanks,

-Kees


-- 
Kees Cook
Pixel Security