media: adv7604: fix possible use-after-free in adv76xx_remove()

This driver's remove path calls cancel_delayed_work(). However, that
function does not wait until the work function finishes. This means
that the callback function may still be running after the driver's
remove function has finished, which would result in a use-after-free.

Fix by calling cancel_delayed_work_sync(), which ensures that
the work is properly cancelled, no longer running, and unable
to re-schedule itself.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Yang Yingliang 2021-04-06 15:42:46 +02:00 committed by Mauro Carvalho Chehab
parent 6107a4fdf8
commit fa56f5f1fe
1 changed files with 1 additions and 1 deletions

View File

@ -3670,7 +3670,7 @@ static int adv76xx_remove(struct i2c_client *client)
io_write(sd, 0x6e, 0);
io_write(sd, 0x73, 0);
cancel_delayed_work(&state->delayed_work_enable_hotplug);
cancel_delayed_work_sync(&state->delayed_work_enable_hotplug);
v4l2_async_unregister_subdev(sd);
media_entity_cleanup(&sd->entity);
adv76xx_unregister_clients(to_state(sd));