Re: [PATCH] USB: input: powermate: fix oops with malicious USB descriptors
From: Dmitry Torokhov
Date: Mon Mar 14 2016 - 12:33:31 EST
On Mon, Mar 14, 2016 at 09:15:48AM -0700, Greg Kroah-Hartman wrote:
> On Mon, Mar 14, 2016 at 10:12:53AM -0400, Josh Boyer wrote:
> > The powermate driver expects at least one valid USB endpoint in its
> > probe function. If given malicious descriptors that specify 0 for
> > the number of endpoints, it will crash. Validate the number of
> > endpoints on the interface before using them.
> > The full report for this issue can be found here:
> > http://seclists.org/bugtraq/2016/Mar/85
> > Reported-by: Ralf Spenneberg <ralf@xxxxxxxxxxxxxx>
> > Cc: stable <stable@xxxxxxxxxxxxxxx>
> > Signed-off-by: Josh Boyer <jwboyer@xxxxxxxxxxxxxxxxx>
> > ---
> > drivers/input/misc/powermate.c | 3 +++
> > 1 file changed, 3 insertions(+)
> I'll queue these up after 4.6-rc1 is out as the merge window is closed
> right now, but we might want to think about a better way to handle this
> type of thing in the USB core. A way to keep from having to add checks
I do not see any reason in holding it until after rc1, applied.
> like this for every single driver, when the driver shouldn't even really
> have their probe function called unless their expected endpoints are
> going to be there.
I had a patch where driver could declare minimal amount of endpoints it
expects to find, but you mentioned we need something more flexible...