USB: serial: metro-usb: stop I/O after failed open

Make sure to kill the interrupt-in URB after a failed open request.
Apart from saving power (and avoiding stale input after a later
successful open), this also prevents a NULL-deref in the completion
handler if the port is manually unbound.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: 704577861d5e ("USB: serial: metro-usb: get data from device in Uni-Directional mode.")
Cc: stable <stable@vger.kernel.org>	# 3.5
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/metro-usb.c b/drivers/usb/serial/metro-usb.c
index cc84da8..4bb29e0 100644 (file)
--- a/drivers/usb/serial/metro-usb.c
+++ b/drivers/usb/serial/metro-usb.c
@@ -188,7 +188,7 @@ static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
                dev_err(&port->dev,
                        "%s - failed submitting interrupt in urb, error code=%d\n",
                        __func__, result);
-               goto exit;
+               return result;
        }
 
        /* Send activate cmd to device */
@@ -197,9 +197,14 @@ static int metrousb_open(struct tty_struct *tty, struct usb_serial_port *port)
                dev_err(&port->dev,
                        "%s - failed to configure device, error code=%d\n",
                        __func__, result);
-               goto exit;
+               goto err_kill_urb;
        }
-exit:
+
+       return 0;
+
+err_kill_urb:
+       usb_kill_urb(port->interrupt_in_urb);
+
        return result;
 }