pps: Fix a use-after free bug when unregistering a source.
authorGeorge Spelvin <linux@horizon.com>
Tue, 12 Feb 2013 07:27:20 +0000 (02:27 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 13 Feb 2013 17:40:35 +0000 (09:40 -0800)
commitd953e0e837e65ecc1ddaa4f9560f7925878a0de6
tree64728d65488a9f85836f570640b1fec863737a52
parent03a7ffe4e542310838bac70ef85acc17536b6d7c
pps: Fix a use-after free bug when unregistering a source.

Remove the cdev from the system (with cdev_del) *before* deallocating it
(in pps_device_destruct, called via kobject_put from device_destroy).

Also prevent deallocating a device with open file handles.

A better long-term fix is probably to remove the cdev from the pps_device
entirely, and instead have all devices reference one global cdev.  Then
the deallocation ordering becomes simpler.

But that's more complex and invasive change, so we leave that
for later.

Signed-off-by: George Spelvin <linux@horizon.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/pps/pps.c