Re: Re: general protection fault in usb_set_interface

[Andrey Konovalov]

On Mon, Dec 16, 2019 at 4:05 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Mon, 16 Dec 2019, Andrey Konovalov wrote:
>
> > On Fri, Dec 13, 2019 at 8:51 PM Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote:
> > >
> > > On Fri, 13 Dec 2019, Andrey Konovalov wrote:
> > >
> > > > > > Let's retry here:
> > > > >
> > > > > > #syz test: https://github.com/google/kasan.git f0df5c1b
> > > > >
> > > > > This bug is already marked as fixed. No point in testing.
> > > > >
> > > >
> > > > Hm, that explains some of the weirdness. It doesn't explain though
> > > > neither why the patch was actually tested when Alan requested it nor
> > > > why syzbot sent no reply.
> > >
> > > In the meantime, is there any way to get syzbot to test the new patch
> > > with the old reproducer?  Perhaps tell it to re-open this bug?
> >
> > No, we can only test this manually now. I can run the reproducer for
> > you. Should I revert the fix for this bug and then apply your patch?
> > What's the expected result?
>
> Please simply run the patch as it is, with no other changes.  The
> expected result is a use-after-free Read in usbvision_v4l2_open, just
> as with c7b0ec009a216143df30.

I've tried to run both the reproducer from this thread and the log
from the other one on 5.5-rc1 with your patch (and other USB fuzzing
patches) applied, but didn't get any crashes.

Thanks!