USB: serial: fix interface refcounting

commit d7971051e4df825e0bc11b995e87bfe86355b8e5 upstream.

Make sure the interface is not released before our serial device.

Note that drivers are still not allowed to access the interface in
any way that may interfere with another driver that may have gotten
bound to the same interface after disconnect returns.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index e4b199cbc97bd31b355e5c99d6c072ee79ef639c..810695b3b4effb3b90173692f4e0eddd374c82ac 100644 (file)
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -168,6 +168,7 @@ static void destroy_serial(struct kref *kref)
                }
        }
 
+       usb_put_intf(serial->interface);
        usb_put_dev(serial->dev);
        kfree(serial);
 }
@@ -625,7 +626,7 @@ static struct usb_serial *create_serial(struct usb_device *dev,
        }
        serial->dev = usb_get_dev(dev);
        serial->type = driver;
-       serial->interface = interface;
+       serial->interface = usb_get_intf(interface);
        kref_init(&serial->kref);
        mutex_init(&serial->disc_mutex);
        serial->minor = SERIAL_TTY_NO_MINOR;