Re: [PATCH v5] usb: gadget: u_serial: Add null pointer check in gserial_resume

[Prashanth K]

On 13-02-23 11:28 pm, Alan Stern wrote:
> On Mon, Feb 13, 2023 at 11:00:38PM +0530, Prashanth K wrote:
> > Consider a case where gserial_disconnect has already cleared
> > gser->ioport. And if a wakeup interrupt triggers afterwards,
> > gserial_resume gets called, which will lead to accessing of
> > gser->ioport and thus causing null pointer dereference.Add
> > a null pointer check to prevent this.
> >
> > Added a static spinlock to prevent gser->ioport from becoming
> > null after the newly added check.
> >
> > Fixes: aba3a8d01d62 ("usb: gadget: u_serial: add suspend resume callbacks")
> > Signed-off-by: Prashanth K <quic_prashk@xxxxxxxxxxx>
> > ---
> > v5: Updated the comment in new patch
>
> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
>
> I'm not very familiar with the u_serial function.  Is it possible for
> gserial_disconnect to cause a similar problem in gserial_suspend?
>
> Alan Stern
Hi Alen,

You were right, we have similar issue in suspend path also. I have 
pushed a patch for the same.

Regards,
Prashanth K