power_supply: Use wrappers to avoid races when registering power supply

Use wrappers over get_property() and set_property() internally in power
supply and for sysfs interface. The wrappers provide safe access if
power supply is not yet registered or t is being destroyed.

In case of syfs the theoretical race could happen between ending of
driver's probe and parallel sysfs access:
some_driver_probe()                    userspace
====================================   ===========================
  drv->psy = power_supply_register()
    device_add()
      sysfs entries are created
    atomic_inc(&psy->use_cnt);
                                       store on sysfs attributes
                                         drv->set_property()
                                           dereference of drv->psy
  drv->psy = returned psy;

For leds the race could happen between power supply being destroyed and
ongoing power_supply_changed_work().

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/power/power_supply_sysfs.c b/drivers/power/power_supply_sysfs.c
index 9134e3d2d95e..af026806cba5 100644
--- a/drivers/power/power_supply_sysfs.c
+++ b/drivers/power/power_supply_sysfs.c
@@ -125,7 +125,7 @@ static ssize_t power_supply_store_property(struct device *dev,
 
 	value.intval = long_val;
 
-	ret = psy->desc->set_property(psy, off, &value);
+	ret = power_supply_set_property(psy, off, &value);
 	if (ret < 0)
 		return ret;