Commit 901f84de authored by Tomasz Duszynski's avatar Tomasz Duszynski Committed by Jonathan Cameron
Browse files

iio: core: fix ioctl handlers removal 



Currently ioctl handlers are removed twice. For the first time during
iio_device_unregister() then later on inside
iio_device_unregister_eventset() and iio_buffers_free_sysfs_and_mask().
Double free leads to kernel panic.

Fix this by not touching ioctl handlers list directly but rather
letting code responsible for registration call the matching cleanup
routine itself.

Fixes: 8dedcc3e ("iio: core: centralize ioctl() calls to the main chardev")
Signed-off-by: default avatarTomasz Duszynski <tomasz.duszynski@octakon.com>
Acked-by: default avatarAlexandru Ardelean <ardeleanalex@gmail.com>
Cc: <Stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20210423080244.2790-1-tomasz.duszynski@octakon.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent f73c7307

drivers/iio/industrialio-core.c

+0 −6
Original line number Diff line number Diff line
@@ -1926,9 +1926,6 @@ EXPORT_SYMBOL(__iio_device_register); 
 **/

void iio_device_unregister(struct iio_dev *indio_dev)

{

	struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);

	struct iio_ioctl_handler *h, *t;



	cdev_device_del(&indio_dev->chrdev, &indio_dev->dev);



	mutex_lock(&indio_dev->info_exist_lock);
@@ -1939,9 +1936,6 @@ void iio_device_unregister(struct iio_dev *indio_dev) 


	indio_dev->info = NULL;



	list_for_each_entry_safe(h, t, &iio_dev_opaque->ioctl_handlers, entry)

		list_del(&h->entry);



	iio_device_wakeup_eventset(indio_dev);

	iio_buffer_wakeup_poll(indio_dev);