USB: fix usbled disconnect read race #2

usbled has a race where show methods for attributes in sysfs can
follow a NULL pointer during disconnect. The correct ordering fixes
it.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/misc/usbled.c b/drivers/usb/misc/usbled.c
index 49c5c5c4c431ee2aabd7ce0b081e913d2634b6f6..06cb71942dc7ee87e52c56c1be0410d64a707be4 100644 (file)
--- a/drivers/usb/misc/usbled.c
+++ b/drivers/usb/misc/usbled.c
@@ -144,12 +144,14 @@ static void led_disconnect(struct usb_interface *interface)
        struct usb_led *dev;
 
        dev = usb_get_intfdata (interface);
-       usb_set_intfdata (interface, NULL);
 
        device_remove_file(&interface->dev, &dev_attr_blue);
        device_remove_file(&interface->dev, &dev_attr_red);
        device_remove_file(&interface->dev, &dev_attr_green);
 
+       /* first remove the files, then set the pointer to NULL */
+       usb_set_intfdata (interface, NULL);
+
        usb_put_dev(dev->udev);
 
        kfree(dev);