| Message ID | 20230415160734.70475-3-hdegoede@redhat.com |
|---|---|
| State | Accepted |
| Commit | f8319774d6f1567d6e7d03653174ab0c82c5c66d |
| Headers | show |
| Series | power: supply: Fix external_power_changed race in several drivers | expand |
diff --git a/drivers/power/supply/axp288_fuel_gauge.c b/drivers/power/supply/axp288_fuel_gauge.c index 05f413178462..3be6f3b10ea4 100644 --- a/drivers/power/supply/axp288_fuel_gauge.c +++ b/drivers/power/supply/axp288_fuel_gauge.c @@ -507,7 +507,7 @@ static void fuel_gauge_external_power_changed(struct power_supply *psy) mutex_lock(&info->lock); info->valid = 0; /* Force updating of the cached registers */ mutex_unlock(&info->lock); - power_supply_changed(info->bat); + power_supply_changed(psy); } static struct power_supply_desc fuel_gauge_desc = {
fuel_gauge_external_power_changed() dereferences info->bat, which gets sets in axp288_fuel_gauge_probe() like this: info->bat = devm_power_supply_register(dev, &fuel_gauge_desc, &psy_cfg); As soon as devm_power_supply_register() has called device_add() the external_power_changed callback can get called. So there is a window where fuel_gauge_external_power_changed() may get called while info->bat has not been set yet leading to a NULL pointer dereference. Fixing this is easy. The external_power_changed callback gets passed the power_supply which will eventually get stored in info->bat, so fuel_gauge_external_power_changed() can simply directly use the passed in psy argument which is always valid. Fixes: 30abb3d07929 ("power: supply: axp288_fuel_gauge: Take lock before updating the valid flag") Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- drivers/power/supply/axp288_fuel_gauge.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)