# Re: \[PATCH\] USB: serial: xr: fix NULL-deref on disconnect

- From: Greg KH \<gregkh@linuxfoundation.org\>
- Date: 2021-02-26 10:21:44 
- List: linux-usb
- Page: https://ratatoskr.run/linux-usb/2021/02/6279930
- Thread: https://ratatoskr.run/linux-usb/2021/02/6279921/t.md

```text
On Fri, Feb 26, 2021 at 11:08:26AM +0100, Johan Hovold wrote:
> Claiming the sibling control interface is a bit more involved and
> specifically requires adding support to USB-serial core for managing
> either interface being unbound first, something which could otherwise
> lead to a NULL-pointer dereference.
> 
> Similarly, additional infrastructure is also needed to handle suspend
> properly.
> 
> Since the driver currently isn't actually using the control interface,
> we can defer this for now by simply not claiming the control interface.
> 
> Fixes: c2d405aa86b4 ("USB: serial: add MaxLinear/Exar USB to Serial driver")
> Reported-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> Cc: Manivannan Sadhasivam <mani@kernel.org>
> Signed-off-by: Johan Hovold <johan@kernel.org>

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
```