[thermal: thermal/next] thermal/core: Protect thermal device operations against thermal device removal

["thermal-bot for Guenter Roeck" <tip-bot2@linutronix.de>]

The following commit has been merged into the thermal/next branch of thermal:

Commit-ID:     b778b4d782d48b9a8751b21deb8eb2f054a3c772
Gitweb:        https://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux.git//b778b4d782d48b9a8751b21deb8eb2f054a3c772
Author:        Guenter Roeck <linux@roeck-us.net>
AuthorDate:    Thu, 10 Nov 2022 07:25:00 -08:00
Committer:     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CommitterDate: Mon, 14 Nov 2022 19:04:37 +01:00

thermal/core: Protect thermal device operations against thermal device removal

Thermal device operations may be called after thermal zone device removal.
After thermal zone device removal, thermal zone device operations must
no longer be called. To prevent such calls from happening, ensure that
the thermal device is registered before executing any thermal device
operations.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/thermal/thermal_core.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 173b049..cc7dbcb 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -203,6 +203,9 @@ int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 	mutex_lock(&thermal_governor_lock);
 	mutex_lock(&tz->lock);
 
+	if (!device_is_registered(&tz->device))
+		goto exit;
+
 	gov = __find_governor(strim(policy));
 	if (!gov)
 		goto exit;
@@ -445,6 +448,12 @@ static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 		return ret;
 	}
 
+	if (!device_is_registered(&tz->device)) {
+		mutex_unlock(&tz->lock);
+
+		return -ENODEV;
+	}
+
 	if (tz->ops->change_mode)
 		ret = tz->ops->change_mode(tz, mode);
 
@@ -486,7 +495,8 @@ void thermal_zone_device_update(struct thermal_zone_device *tz,
 				enum thermal_notify_event event)
 {
 	mutex_lock(&tz->lock);
-	__thermal_zone_device_update(tz, event);
+	if (device_is_registered(&tz->device))
+		__thermal_zone_device_update(tz, event);
 	mutex_unlock(&tz->lock);
 }
 EXPORT_SYMBOL_GPL(thermal_zone_device_update);