diff mbox series

[4.19,062/425] media: adv7604: fix possible use-after-free in adv76xx_remove()

Message ID 20210520092133.476798135@linuxfoundation.org
State Superseded
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman May 20, 2021, 9:17 a.m. UTC 
From: Yang Yingliang <yangyingliang@huawei.com>

[ 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 <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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/i2c/adv7604.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c
index a4b0a89c7e7e..04577d409e63 100644
--- a/drivers/media/i2c/adv7604.c
+++ b/drivers/media/i2c/adv7604.c
@@ -3560,7 +3560,7 @@  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));