Re: [PATCH 2/2] usb/usbip: Fix v_recv_cmd_submit() to use PIPE_BULK define

[Shuah Khan]

On 11/3/22 07:24, Greg KH wrote:
> On Thu, Nov 03, 2022 at 07:12:43AM -0600, Shuah Khan wrote:
> > Fix v_recv_cmd_submit() to use PIPE_BULK define instead of hard coded
> > values. This also fixes the following signed integer overflow error
> > reported by cppcheck. This is not an issue since pipe is unsigned int.
> > However, this change improves the code to use proper define.
> >
> > drivers/usb/usbip/vudc_rx.c:152:26: error: Signed integer overflow for expression '3<<30'. [integerOverflow]
> >   urb_p->urb->pipe &= ~(3 << 30);
> >
> > In addition, add a sanity check for PIPE_BULK != 3 as the code path depends
> > on PIPE_BULK = 3.
> >
> > Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
> > ---
> >   drivers/usb/usbip/vudc_rx.c | 5 ++++-
> >   1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/usbip/vudc_rx.c b/drivers/usb/usbip/vudc_rx.c
> > index a6ca27f10b68..e7e0eb6bbca0 100644
> > --- a/drivers/usb/usbip/vudc_rx.c
> > +++ b/drivers/usb/usbip/vudc_rx.c
> > @@ -149,7 +149,10 @@ static int v_recv_cmd_submit(struct vudc *udc,
> >   	urb_p->urb->status = -EINPROGRESS;
> >   
> >   	/* FIXME: more pipe setup to please usbip_common */
> > -	urb_p->urb->pipe &= ~(3 << 30);
> > +#if PIPE_BULK != 3
> > +#error "Sanity check failed, this code presumes PIPE_... to range from 0 to 3"
> > +#endif
>
> Perhaps use BUILD_BUG_ON() instead of hand-rolling one?

Makes sense. I will send v2.

thanks,
-- Shuah