Re: [syzbot] WARNING in rtl8152_probe

[Oliver Neukum]

Am Montag, den 17.05.2021, 01:01 +0000 schrieb Hayes Wang:
> Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
> > Sent: Friday, May 14, 2021 11:33 PM

> > So if a peculiar emulated device created by syzbot is capable of
> > crashing the driver, then somewhere there is a bug which needs to
> > be
> > fixed.  It's true that fixing all these bugs might not protect
> > against a
> > malicious device which deliberately behaves in an apparently
> > reasonable
> > manner.  But it does reduce the attack surface.
> 
> Thanks for your response.
> I will add some checks.

Hi,

the problem in this particular case is in
static bool rtl_vendor_mode(struct usb_interface *intf)
which accepts any config number. It needs to bail out
if you find config #0 to be what the descriptors say,
treating that as an unrecoverable error.

	Regards
		Oliver