From: Yang Yingliang Date: Tue, 6 Apr 2021 13:42:46 +0000 (+0200) Subject: media: adv7604: fix possible use-after-free in adv76xx_remove() X-Git-Tag: v5.11.20~139 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ce27007a6ed00c64ce7f9b119f9eb540c26b2449;p=thirdparty%2Fkernel%2Fstable.git media: adv7604: fix possible use-after-free in adv76xx_remove() [ Upstream commit fa56f5f1fe31c2050675fa63b84963ebd504a5b3 ] 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/adv7604.c b/drivers/media/i2c/adv7604.c index 09004d928d11f..d1f58795794fd 100644 --- a/drivers/media/i2c/adv7604.c +++ b/drivers/media/i2c/adv7604.c @@ -3616,7 +3616,7 @@ 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));