[PATCH AUTOSEL 5.12 099/102] thermal/core/thermal_of: Stop zone device before unregistering it

From: Sasha Levin
Date: Wed Jul 14 2021 - 15:48:37 EST


From: Dmitry Osipenko <digetx@xxxxxxxxx>

[ Upstream commit 5e5c9f9a75fc4532980c2e699caf8a36070a3a2e ]

Zone device is enabled after thermal_zone_of_sensor_register() completion,
but it's not disabled before senor is unregistered, leaving temperature
polling active. This results in accessing a disabled zone device and
produces a warning about this problem. Stop zone device before
unregistering it in order to fix this "use-after-free" problem.

Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210616190417.32214-3-digetx@xxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/thermal/thermal_of.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
index 5b76f9a1280d..6379f26a335f 100644
--- a/drivers/thermal/thermal_of.c
+++ b/drivers/thermal/thermal_of.c
@@ -559,6 +559,9 @@ void thermal_zone_of_sensor_unregister(struct device *dev,
if (!tz)
return;

+ /* stop temperature polling */
+ thermal_zone_device_disable(tzd);
+
mutex_lock(&tzd->lock);
tzd->ops->get_temp = NULL;
tzd->ops->get_trend = NULL;
--
2.30.2