From: Yang Yingliang Date: Tue, 6 Apr 2021 13:48:12 +0000 (+0200) Subject: media: i2c: adv7511-v4l2: fix possible use-after-free in adv7511_remove() X-Git-Tag: v4.4.269~155 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1a4e1d660a6e63ae19f8c7600a8753bfb9cb2f96;p=thirdparty%2Fkernel%2Fstable.git 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 Signed-off-by: Yang Yingliang Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- diff --git a/drivers/media/i2c/adv7511-v4l2.c b/drivers/media/i2c/adv7511-v4l2.c index b35400e4e9af8..e85777dfe81d9 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);