RE: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference

From: Peter Chen
Date: Mon Mar 09 2015 - 22:18:19 EST



> > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > req = container_of(_req, struct lpc32xx_request, req);
> > ep = container_of(_ep, struct lpc32xx_ep, ep);
> >
> > - if (!_req || !_req->complete || !_req->buf ||
> > + if (!_ep || !_req || !_req->complete || !_req->buf ||
> > !list_empty(&req->queue))
> > return -EINVAL;
> >
> > @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > }
> >
> >
> > - if ((!udc) || (!udc->driver) ||
> > - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN))
> {
> > dev_dbg(udc->dev, "invalid device\n");
> > return -EINVAL;
> > }
>
> what's going to happen here ?
>

I just changed the current code, in fact, udc->driver is impossible to NULL which
is cleared at .udc_stop.

The speed is possible for unknown if the reset has occurred at that time.

Peter
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/