Re: usb/uwb: GPF in uwbd_start

From: Andrey Konovalov
Date: Wed Sep 13 2017 - 11:12:32 EST


On Tue, Sep 12, 2017 at 9:55 PM, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, Sep 12, 2017 at 07:10:07PM +0200, Andrey Konovalov wrote:
>> Hi!
>>
>> I've got the following crashes while fuzzing the kernel with syzkaller.
>>
>> On commit 81a84ad3cb5711cec79f4dd53a4ce026b092c432 (Sep 3).
>>
>> uwbd_start() calls kthread_run() and checks that the return value in
>> not NULL. But the return value is not NULL in case kthread_run()
>> fails, it takes the form of ERR_PTR(-EINTR).
>
> Great, do you want to write a patch for this, or do you want me to?

Just mailed a patch.

>
> And I'm guessing you really don't have the real hardware for this
> device, right?

I don't have a hardware reproducer, but making it is just a question
of effort. There's the Facedancer21 board [1], which can be used to
emulate arbitrary USB devices. It's also possible to do this with with
something like Raspberry Pi Zero in USB gadget mode through gadgetfs.

[1] https://int3.cc/products/facedancer21

>
> thanks,
>
> greg k-h