power: supply: da9150: Fix use after free bug in da9150_charger_remove due to race...

[ Upstream commit 06615d11cc78162dfd5116efb71f29eb29502d37 ]

In da9150_charger_probe, &charger->otg_work is bound with
da9150_charger_otg_work. da9150_charger_otg_ncb may be
called to start the work.

If we remove the module which will call da9150_charger_remove
to make cleanup, there may be a unfinished work. The possible
sequence is as follows:

Fix it by canceling the work before cleanup in the da9150_charger_remove

CPU0                  CPUc1

                    |da9150_charger_otg_work
da9150_charger_remove      |
power_supply_unregister  |
device_unregister   |
power_supply_dev_release|
kfree(psy)          |
                    |
                    | 	power_supply_changed(charger->usb);
                    |   //use

Fixes: c1a281e34dae ("power: Add support for DA9150 Charger")
Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/power/supply/da9150-charger.c b/drivers/power/supply/da9150-charger.c
index f9314cc..6b987da 100644 (file)
--- a/drivers/power/supply/da9150-charger.c
+++ b/drivers/power/supply/da9150-charger.c
@@ -662,6 +662,7 @@ static int da9150_charger_remove(struct platform_device *pdev)
 
        if (!IS_ERR_OR_NULL(charger->usb_phy))
                usb_unregister_notifier(charger->usb_phy, &charger->otg_nb);
+       cancel_work_sync(&charger->otg_work);
 
        power_supply_unregister(charger->battery);
        power_supply_unregister(charger->usb);