diff mbox series

[v2,6/9] thermal/core: Protect hwmon accesses to thermal operations with thermal zone mutex

Message ID 20221110152500.3032655-7-linux@roeck-us.net
State New
Headers
Series thermal/core: Protect thermal device operations against removal |

Commit Message

Guenter Roeck Nov. 10, 2022, 3:24 p.m. UTC 
  In preparation to protecting access to thermal operations against thermal
zone device removal, protect hwmon accesses to thermal zone operations
with the thermal zone mutex. After acquiring the mutex, ensure that the
thermal zone device is registered before proceeding.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v2: Simplify error handling to avoid additional goto.
    Do not use ternary operator in modified code.

 drivers/thermal/thermal_hwmon.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/thermal/thermal_hwmon.c b/drivers/thermal/thermal_hwmon.c
index f53f4ceb6a5d..c594c42bea6d 100644
--- a/drivers/thermal/thermal_hwmon.c
+++ b/drivers/thermal/thermal_hwmon.c
@@ -77,7 +77,15 @@  temp_crit_show(struct device *dev, struct device_attribute *attr, char *buf)
 	int temperature;
 	int ret;
 
-	ret = tz->ops->get_crit_temp(tz, &temperature);
+	mutex_lock(&tz->lock);
+
+	if (device_is_registered(&tz->device))
+		ret = tz->ops->get_crit_temp(tz, &temperature);
+	else
+		ret = -ENODEV;
+
+	mutex_unlock(&tz->lock);
+
 	if (ret)
 		return ret;