Re: [PATCH] HID: USB: Fix general protection fault caused by Logitech driver

[Jiri Kosina <jikos@kernel.org>]

On Thu, 22 Aug 2019, Alan Stern wrote:

> > > > I've ran the fuzzer with your patches applied overnight and noticed
> > > > another fallout of similar bugs. I think they are caused by a similar
> > > > issue in the sony HID driver. There's no hid_hw_stop() call in the "if
> > > > (!(hdev->claimed & HID_CLAIMED_INPUT))" case in sony_probe(). Does it
> > > > look like a bug to you?
> > >
> > > It looks like the relevant hid_hw_stop() call is the one at the end of
> > > sony_configure_input().  But I can't tell if doing that way is valid or
> > > not -- in practice the code would end up calling hid_disconnect() while
> > > hid_connect() was still running, which doesn't seem like a good idea.
> > >
> > > There's a comment about this near the end of sony_probe().  I suspect
> > > it would be better to call hid_hw_stop() in the conditional code
> > > following that comment rather than in sony_configure_input().
> > >
> > > Either way, these are all things Jiri should know about or check up on.
> > >
> > > Have you gotten any test results from syzbot exercising these pathways?
> > > You ought to be able to tell which HID driver is involved by looking
> > > through the console output.
> > 
> > Yes, a typical crash is below, that's why I thought it's the sony
> > driver. Adding hid_hw_stop() in sony_probe() stops the issue from
> > happening, but I don't know whether it's the right fix.
> 
> Probably you have to add hid_hw_stop() in sony_probe() and remove it 
> from sony_configure_input().  But like I said above, Jiri should look 
> into this.

It almost certainly is, thanks.

Adding Roderick to CC ... Roderick, will you be able to test and submit 
a patch fixing that?

-- 
Jiri Kosina
SUSE Labs