On Mon, 1 Jul 2013, Felipe Balbi wrote: > bInterval must be within the range 1 - 16,
That's true only for high speed and SuperSpeed. For low speed and full speed, bInterval is allowed to range from 1 to 255. See p. 271 in the USB-2 spec. > in order to catch drivers passing a too > large bInterval (thus zeroing urb->interval), > let's clamp() the argument to the allowed > range. > > Signed-off-by: Felipe Balbi <ba...@ti.com> > --- > include/linux/usb.h | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/include/linux/usb.h b/include/linux/usb.h > index a232b7e..0883e3a 100644 > --- a/include/linux/usb.h > +++ b/include/linux/usb.h > @@ -1545,6 +1545,10 @@ static inline void usb_fill_int_urb(struct urb *urb, > urb->transfer_buffer_length = buffer_length; > urb->complete = complete_fn; > urb->context = context; > + > + /* make sure interval is within allowed range */ > + interval = clamp(interval, 1, 16); These lines should go within the first branch of the "if" statement below. > + > if (dev->speed == USB_SPEED_HIGH || dev->speed == USB_SPEED_SUPER) > urb->interval = 1 << (interval - 1); > else Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
