powercap: fix possible name leak in powercap_register_zone()

In the error path after calling dev_set_name(), the device
name is leaked. To fix this, calling dev_set_name() before
device_register(), and call put_device() if it returns error.

All the resources is released in powercap_release(), so it
can return from powercap_register_zone() directly.

Fixes: 75d2364ea0ca ("PowerCap: Add class driver")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c
index 1f96835..e180dee 100644 (file)
--- a/drivers/powercap/powercap_sys.c
+++ b/drivers/powercap/powercap_sys.c
@@ -530,9 +530,6 @@ struct powercap_zone *powercap_register_zone(
        power_zone->name = kstrdup(name, GFP_KERNEL);
        if (!power_zone->name)
                goto err_name_alloc;
-       dev_set_name(&power_zone->dev, "%s:%x",
-                                       dev_name(power_zone->dev.parent),
-                                       power_zone->id);
        power_zone->constraints = kcalloc(nr_constraints,
                                          sizeof(*power_zone->constraints),
                                          GFP_KERNEL);
@@ -555,9 +552,16 @@ struct powercap_zone *powercap_register_zone(
        power_zone->dev_attr_groups[0] = &power_zone->dev_zone_attr_group;
        power_zone->dev_attr_groups[1] = NULL;
        power_zone->dev.groups = power_zone->dev_attr_groups;
+       dev_set_name(&power_zone->dev, "%s:%x",
+                                       dev_name(power_zone->dev.parent),
+                                       power_zone->id);
        result = device_register(&power_zone->dev);
-       if (result)
-               goto err_dev_ret;
+       if (result) {
+               put_device(&power_zone->dev);
+               mutex_unlock(&control_type->lock);
+
+               return ERR_PTR(result);
+       }
 
        control_type->nr_zones++;
        mutex_unlock(&control_type->lock);