This is a note to let you know that I've just added the patch titled media: i2c: adv7511-v4l2: fix possible use-after-free in adv7511_remove() to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: media-i2c-adv7511-v4l2-fix-possible-use-after-free-i.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f591283510ab9d7a4b29a2985aa5f5dda716defd Author: Yang Yingliang <yangyingliang@xxxxxxxxxx> Date: Tue Apr 6 15:48:12 2021 +0200 media: i2c: adv7511-v4l2: fix possible use-after-free in adv7511_remove() [ Upstream commit 2c9541720c66899adf6f3600984cf3ef151295ad ] 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@xxxxxxxxxx> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/media/i2c/adv7511-v4l2.c b/drivers/media/i2c/adv7511-v4l2.c index b35400e4e9af..e85777dfe81d 100644 --- a/drivers/media/i2c/adv7511-v4l2.c +++ b/drivers/media/i2c/adv7511-v4l2.c @@ -1570,7 +1570,7 @@ static int adv7511_remove(struct i2c_client *client) client->addr << 1, client->adapter->name); adv7511_init_setup(sd); - cancel_delayed_work(&state->edid_handler); + cancel_delayed_work_sync(&state->edid_handler); i2c_unregister_device(state->i2c_edid); i2c_unregister_device(state->i2c_pktmem); destroy_workqueue(state->work_queue);