2017-12-12 20:55:08

by Gustavo A. R. Silva

[permalink] [raw]
Subject: Re: [PATCH] au0828: fix use-after-free at USB probing

Hey Andrey,

Quoting Andrey Konovalov <[email protected]>:

> On Thu, Nov 23, 2017 at 2:31 AM, Gustavo A. R. Silva
> <[email protected]> wrote:
>> Hi Andrey,
>>
>> I have successfully installed and tested syzkaller with QEMU. Can you please
>> tell me how to reproduce this bug or share with me the full crash report?
>>
>> Also, can you point me out to the PoC file?
>
> Hi Gustavo,
>
> Sorry for the delay.
>

No worries.

> I've now published the USB fuzzing prototype, so here's how you can
> reproduce this:
>
> 1. Get Linux 4.15-rc3 upstream kernel
> (50c4c4e268a2d7a3e58ebb698ac74da0de40ae36).
>
> 2. Apply this patch (it adds a new interface to emulate USB devices):
> https://github.com/google/syzkaller/blob/usb-fuzzer/tools/usb/0002-usb-fuzzer-main-usb-gadget-fuzzer-driver.patch
>
> 3. Build the kernel with the attached .config (you need relatively new
> GCC to make KASAN work).
>
> 4. Run the attached reproducer.
>
> Also attaching the full kernel log.
>

Awesome. :D I'll try this.

Thank you!
--
Gustavo A. R. Silva