Input: xpad - validate USB endpoint count during probe

commit caca925f upstream.

This prevents a malicious USB device from causing an oops.
Signed-off-by: Cameron Gutman <aicommander@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/input/joystick/xpad.c

@@ -883,6 +883,9 @@ static int xpad_probe(struct usb_interface *intf, const struct usb_device_id *id
 	struct usb_endpoint_descriptor *ep_irq_in;
 	int i, error;
 
+	if (intf->cur_altsetting->desc.bNumEndpoints != 2)
+		return -ENODEV;
+
 	for (i = 0; xpad_device[i].idVendor; i++) {
 		if ((le16_to_cpu(udev->descriptor.idVendor) == xpad_device[i].idVendor) &&
 		    (le16_to_cpu(udev->descriptor.idProduct) == xpad_device[i].idProduct))