diff options
author | Viresh Kumar <viresh.kumar@linaro.org> | 2022-10-17 13:03:01 +0300 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2022-10-25 19:58:11 +0300 |
commit | c408b3d1d9bbc7de5fb0304fea424ef2539da616 (patch) | |
tree | 4df01a831c649894ec6666e0e5758b5ccbe457e1 /drivers/thermal/thermal_sysfs.c | |
parent | 247f34f7b80357943234f93f247a1ae6b6c3a740 (diff) | |
download | linux-c408b3d1d9bbc7de5fb0304fea424ef2539da616.tar.xz |
thermal: Validate new state in cur_state_store()
In cur_state_store(), the new state of the cooling device is received
from user-space and is not validated by the thermal core but the same is
left for the individual drivers to take care of. Apart from duplicating
the code it leaves possibility for introducing bugs where a driver may
not do it right.
Lets make the thermal core check the new state itself and store the max
value in the cooling device structure.
Link: https://lore.kernel.org/all/Y0ltRJRjO7AkawvE@kili/
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/thermal/thermal_sysfs.c')
-rw-r--r-- | drivers/thermal/thermal_sysfs.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index ec495c7dff03..bd7596125461 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -589,13 +589,8 @@ static ssize_t max_state_show(struct device *dev, struct device_attribute *attr, char *buf) { struct thermal_cooling_device *cdev = to_cooling_device(dev); - unsigned long state; - int ret; - ret = cdev->ops->get_max_state(cdev, &state); - if (ret) - return ret; - return sprintf(buf, "%ld\n", state); + return sprintf(buf, "%ld\n", cdev->max_state); } static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr, @@ -625,6 +620,10 @@ cur_state_store(struct device *dev, struct device_attribute *attr, if ((long)state < 0) return -EINVAL; + /* Requested state should be less than max_state + 1 */ + if (state > cdev->max_state) + return -EINVAL; + mutex_lock(&cdev->lock); result = cdev->ops->set_cur_state(cdev, state); |