staging: usbip: vhci: use urb->dev->portnum to find port

The access to pending_port was racy when two devices
were being attached at the same time.

Signed-off-by: Max Vozeler <[e-mail]>
Tested-by: Mark Wehby <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/usbip/vhci.h

···
 	 * But, the index of this array begins from 0.
 	 */
 	struct vhci_device vdev[VHCI_NPORTS];
-
-	/* vhci_device which has not been assiged its address yet */
-	int pending_port;
 };
 
 

drivers/staging/usbip/vhci_hcd.c

···
 	 * the_controller->vdev[rhport].ud.status = VDEV_CONNECT;
 	 * spin_unlock(&the_controller->vdev[rhport].ud.lock); */
 
-	the_controller->pending_port = rhport;
-
 	spin_unlock_irqrestore(&the_controller->lock, flags);
 
 	usb_hcd_poll_rh_status(vhci_to_hcd(the_controller));
···
 		return urb->status;
 	}
 
-	vdev = port_to_vdev(the_controller->pending_port);
+	vdev = port_to_vdev(urb->dev->portnum-1);
 
 	/* refuse enqueue for dead connection */
 	spin_lock(&vdev->ud.lock);