[PATCH 4.9 69/94] USB: usbdevfs: restore warning for nonsensical flags

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Oliver Neukum <oneukum@xxxxxxxx>

commit 81e0403b26d94360abd1f6a57311337973bc82cd upstream.

If we filter flags before they reach the core we need to generate our
own warnings.

Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Fixes: 0cb54a3e47cb ("USB: debugging code shouldn't alter control flow")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/core/devio.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1714,6 +1714,11 @@ static int proc_do_submiturb(struct usb_
 		u |= URB_NO_INTERRUPT;
 	as->urb->transfer_flags = u;
 
+	if (!allow_short && uurb->flags & USBDEVFS_URB_SHORT_NOT_OK)
+		dev_warn(&ps->dev->dev, "Requested nonsensical USBDEVFS_URB_SHORT_NOT_OK.\n");
+	if (!allow_zero && uurb->flags & USBDEVFS_URB_ZERO_PACKET)
+		dev_warn(&ps->dev->dev, "Requested nonsensical USBDEVFS_URB_ZERO_PACKET.\n");
+
 	as->urb->transfer_buffer_length = uurb->buffer_length;
 	as->urb->setup_packet = (unsigned char *)dr;
 	dr = NULL;