Re: KASAN: vmalloc-out-of-bounds Write in snd_pcm_hw_params

From: Dipanjan Das
Date: Thu Jul 28 2022 - 19:24:31 EST


On Tue, Jul 26, 2022 at 10:25 PM Takashi Iwai <tiwai@xxxxxxx> wrote:
>
> Thanks for the analysis. A good news is that, at least for the
> vmalloc() case, it's a kind of false-positive; vmalloc() always takes
> the full pages, so practically seen, the size is page-aligned. It's
> fooling the memory checker, though.
>
> But the similar problem could be seen with genalloc calls, and this
> was fixed by the upstream commit
> 5c1733e33c888a3cb7f576564d8ad543d5ad4a9e
> ALSA: memalloc: Align buffer allocations in page size
>
> I suppose you can simply backport this commit to 5.10.y. Could you
> confirm that this fixes your problem?

We confirm that the patch you proposed fixes the problem (blocks the
reproducer). How do we proceed with getting the issue fixed? Do we
send a patch according to the steps detailed here:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html?

--
Thanks and Regards,

Dipanjan