On Mon, Jun 26, 2023 at 07:48:05AM +0200, Jan Beulich wrote: > On 25.06.2023 18:42, Zhang Shurong wrote: > > --- a/drivers/usb/host/xen-hcd.c > > +++ b/drivers/usb/host/xen-hcd.c > > @@ -456,6 +456,8 @@ static int xenhcd_hub_control(struct usb_hcd *hcd, __u16 typeReq, __u16 wValue, > > info->ports[wIndex - 1].c_connection = false; > > fallthrough; > > default: > > + if (wValue >= 32) > > + goto error; > > info->ports[wIndex - 1].status &= ~(1 << wValue); > > Even 31 is out of bounds (as in: UB) as long as it's 1 here rather > than 1u. Why isn't the caller fixed so this type of value could never be passed to the hub_control callback? thanks, greg k-h
