tree ad8d671b87c667e8eeb4e6ae97811132cecfddbe
parent af5e1a68318e2ed2de22fc2d7a02f2882abe073c
author Martin Fuzzey <mfuzzey@parkeon.com> 1424355464 +0100
committer Jonathan Cameron <jic23@kernel.org> 1426359254 +0000

iio: core: Fix double free.

When an error occurred during event registration memory was freed twice
resulting in kernel memory corruption and a crash in unrelated code.

The problem was caused by
	iio_device_unregister_eventset()
	iio_device_unregister_sysfs()

being called twice, once on the error path and then
again via iio_dev_release().

Fix this by making these two functions idempotent so they
may be called multiple times.

The problem was observed before applying
	78b33216 iio:core: Handle error when mask type is not separate

Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>