[PATCH v4 2/6] thermal: thermal_of: Stop zone device before unregistering it

From: Dmitry Osipenko <digetx@gmail.com>
To: Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Zhang Rui <rui.zhang@intel.com>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Amit Kucheria <amitk@kernel.org>,
	Andreas Westman Dorcsak <hedmoo@yahoo.com>,
	Maxim Schwalm <maxim.schwalm@gmail.com>,
	Svyatoslav Ryhel <clamor95@gmail.com>,
	Ihor Didenko <tailormoon@rambler.ru>,
	Ion Agorria <ion@agorria.com>,
	Matt Merhar <mattmerhar@protonmail.com>,
	Peter Geis <pgwipeout@gmail.com>
Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org
Subject: [PATCH v4 2/6] thermal: thermal_of: Stop zone device before unregistering it
Date: Wed, 16 Jun 2021 22:04:13 +0300	[thread overview]
Message-ID: <20210616190417.32214-3-digetx@gmail.com> (raw)
In-Reply-To: <20210616190417.32214-1-digetx@gmail.com>

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@gmail.com>
---
 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

