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

From: Aleksandr Nogikh
Date: Thu Jul 20 2023 - 07:55:31 EST


On Wed, Jul 12, 2023 at 11:11 PM Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>
> On Tue, Jul 11, 2023 at 06:00:08AM -0700, syzbot wrote:
> > This bug is marked as fixed by commit:
> > media: uvcvideo: Avoid cyclic entity chains due to malformed
> >
> > But I can't find it in the tested trees[1] for more than 90 days.
> > Is it a correct commit? Please update it by replying:
>
> #syz fix: media: uvcvideo: Avoid cyclic entity chains due to malformed USB descriptors

Thanks for providing the correct name!

>
> Can a commit ID be used as well ?

The problem with commit hashes is that we fuzz quite a number of
different Linux trees and every new commit might appear in all of them
with totally different hashes. Name is a much more reliable
identifier, so that's what we currently require in #syz fix.

>
> > Until then the bug is still considered open and new crashes with
> > the same signature are ignored.
> >
> > Kernel: Linux
> > Dashboard link: https://syzkaller.appspot.com/bug?extid=0b0095300dfeb8a83dc8
> >
> > ---
> > [1] I expect the commit to be present in:
> >
> > 1. for-kernelci branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git
> >
> > 2. master branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git
> >
> > 3. master branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git
> >
> > 4. main branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git
> >
> > The full list of 9 trees can be found at
> > https://syzkaller.appspot.com/upstream/repos
>
> --
> Regards,
>
> Laurent Pinchart