[PATCH 4.4 27/28] USB: serial: console: fix use-after-free after failed setup

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@xxxxxxxxxx>

commit 299d7572e46f98534033a9e65973f13ad1ce9047 upstream.

Make sure to reset the USB-console port pointer when console setup fails
in order to avoid having the struct usb_serial be prematurely freed by
the console code when the device is later disconnected.

Fixes: 73e487fdb75f ("[PATCH] USB console: fix disconnection issues")
Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/serial/console.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -189,6 +189,7 @@ static int usb_console_setup(struct cons
 	tty_kref_put(tty);
  reset_open_count:
 	port->port.count = 0;
+	info->port = NULL;
 	usb_autopm_put_interface(serial->interface);
  error_get_interface:
 	usb_serial_put(serial);