usb: gadget: storage: check for valid USB_BULK_RESET_REQUEST wLength

The USB-IF CV compliance tester is getting stricter, and it would
be valid for it to fail a mass-storage device that accepts an
invalid USB_BULK_RESET_REQUEST request. Although it doesn't do
that yet, let's be proactive and fix that now.

Suggested by Alan Stern.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/f_mass_storage.c

@@ -624,7 +624,8 @@ static int fsg_setup(struct usb_function *f,
 		if (ctrl->bRequestType !=
 		    (USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 			break;
-		if (w_index != fsg->interface_number || w_value != 0)
+		if (w_index != fsg->interface_number || w_value != 0 ||
+				w_length != 0)
 			return -EDOM;
 
 		/*

drivers/usb/gadget/file_storage.c

@@ -859,7 +859,7 @@ static int class_setup_req(struct fsg_dev *fsg,
 			if (ctrl->bRequestType != (USB_DIR_OUT |
 					USB_TYPE_CLASS | USB_RECIP_INTERFACE))
 				break;
-			if (w_index != 0 || w_value != 0) {
+			if (w_index != 0 || w_value != 0 || w_length != 0) {
 				value = -EDOM;
 				break;
 			}