Re: usercopy whitelist woe in scsi_sense_cache

From: Kees Cook
Date: Fri Apr 20 2018 - 16:23:30 EST


On Thu, Apr 19, 2018 at 2:32 AM, Paolo Valente <paolo.valente@xxxxxxxxxx> wrote:
> I'm missing something here. When the request gets completed in the
> first place, the hook bfq_finish_requeue_request gets called, and that
> hook clears both ->elv.priv elements (as the request has a non-null
> elv.icq). So, when bfq gets the same request again, those elements
> must be NULL. What am I getting wrong?
>
> I have some more concern on this point, but I'll stick to this for the
> moment, to not create more confusion.

I don't know the "how", I only found the "what". :) If you want, grab
the reproducer VM linked to earlier in this thread; it'll hit the
problem within about 30 seconds of running the reproducer.

-Kees

--
Kees Cook
Pixel Security