From: Richard Pearman <richard.pearman@intellect.com.au>
From: Greg Breen <greg.breen@intellect.com.au>

When an error occurs in serial_open() ensure that port->tty and 
tty->driver_data are set  to NULL, if previously assigned a value in the 
function.

Signed-off-by: Richard S. Pearman <richard.pearman@intellect.com.au>
---
--- linux-2.6.17.1/drivers/usb/serial/usb-serial.c.orig    Mon Oct 22 
11:12:29 2007
+++ linux-2.6.17.1/drivers/usb/serial/usb-serial.c    Mon Oct 22 
11:12:23 2007
@@ -230,6 +230,8 @@ bailout_module_put:
     module_put(serial->type->driver.owner);
 bailout_mutex_unlock:
     port->open_count = 0;
+    port->tty = NULL;
+    tty->driver_data = NULL;   
     mutex_unlock(&port->mutex);
 bailout_kref_put:
     kref_put(&serial->kref, destroy_serial);