Re: [syzbot] KASAN: use-after-free Read in fw_load_sysfs_fallback

From: Greg KH
Date: Wed Jun 02 2021 - 13:56:42 EST


On Wed, Jun 02, 2021 at 10:08:39AM -0700, SyzScope wrote:
> Hi,
> We have analyzed this bug and realize that it is security-critical.
> Specifically, according to our investigation, it will lead to a
> use-after-free write (instead of the originally reported use-after-free
> read) and thus highly likely exploitable. More details can be found at:
>
> https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-fw_load_sysfs_fallback <https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-fw_load_sysfs_fallback>
>
>
> We understand that creating a patch can be time-consuming and there is
> probably a long list of bugs pending fixes. We hope that our security
> analysis can enable an informed decision on which bugs to fix first
> (prioritization).
>
> Since the bug has been on syzbot for over two months (first found on
> 03-22-2020), it is best to have the bug fixed early enough to avoid it being
> weaponized.

Great, please work to provide a fix! See the archives for more details
if you are curious about this.

thanks,

greg k-h