power: supply: max14656: fix potential use-after-free

Explicitly cancel/sync the irq_work delayed work, otherwise
there's a chance that it will run after the device is removed,
which would result in a use-after-free.

Note that cancel/sync should happen:
- after irq's have been disabled, as the isr re-schedules the work
- before the power supply is unregistered, because the work func
    uses the power supply handle.

Cc: Alexander Kurz <akurz@blala.de>
Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
This commit is contained in:
Sven Van Asbroeck 2019-02-15 16:43:03 -05:00 committed by Sebastian Reichel
parent 0cd0e49711
commit 252fbeb86c

View File

@ -240,6 +240,14 @@ static enum power_supply_property max14656_battery_props[] = {
POWER_SUPPLY_PROP_MANUFACTURER,
};
static void stop_irq_work(void *data)
{
struct max14656_chip *chip = data;
cancel_delayed_work_sync(&chip->irq_work);
}
static int max14656_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@ -278,8 +286,6 @@ static int max14656_probe(struct i2c_client *client,
if (ret)
return -ENODEV;
INIT_DELAYED_WORK(&chip->irq_work, max14656_irq_worker);
chip->detect_psy = devm_power_supply_register(dev,
&chip->psy_desc, &psy_cfg);
if (IS_ERR(chip->detect_psy)) {
@ -287,6 +293,13 @@ static int max14656_probe(struct i2c_client *client,
return -EINVAL;
}
INIT_DELAYED_WORK(&chip->irq_work, max14656_irq_worker);
ret = devm_add_action(dev, stop_irq_work, chip);
if (ret) {
dev_err(dev, "devm_add_action %d failed\n", ret);
return ret;
}
ret = devm_request_irq(dev, chip->irq, max14656_irq,
IRQF_TRIGGER_FALLING,
MAX14656_NAME, chip);