static void usbhid_disconnect(struct usb_interface *intf)
{
	struct hid_device *hid = usb_get_intfdata(intf);
	struct usbhid_device *usbhid;

	if (WARN_ON(!hid))
		return;

	usbhid = hid->driver_data;
	spin_lock_irq(&usbhid->lock);	/* Sync with error and led handlers */
	set_bit(HID_DISCONNECTED, &usbhid->iofl);
	spin_unlock_irq(&usbhid->lock);
	hid_destroy_device(hid);
	kfree(usbhid);
}

The product reads data past the end, or before the beginning, of the intended buffer.