| Message ID | 20230309174728.233732-1-zyytlz.wz@163.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere, archived |
| Headers | show |
| Series | power: supply: bq24190: Fix use after free bug in bq24190_remove due to race condition | expand |
Hi, On Fri, Mar 10, 2023 at 01:47:28AM +0800, Zheng Wang wrote: > In bq24190_probe, &bdi->input_current_limit_work is bound > with bq24190_input_current_limit_work. When external power > changed, it will call bq24190_charger_external_power_changed > to start the work. > > If we remove the module which will call bq24190_remove to make > cleanup, there may be a unfinished work. The possible > sequence is as follows: > > CPU0 CPUc1 > > |bq24190_input_current_limit_work > bq24190_remove | > power_supply_unregister | > device_unregister | > power_supply_dev_release| > kfree(psy) | > | > | power_supply_get_property_from_supplier > | //use > > Fix it by finishing the work before cleanup in the bq24190_remove > > Fixes: 97774672573a ("power_supply: Initialize changed_work before calling device_add") > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > --- Thanks, queued to fixes branch. -- Sebastian > drivers/power/supply/bq24190_charger.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/power/supply/bq24190_charger.c b/drivers/power/supply/bq24190_charger.c > index be34b9848450..de67b985f0a9 100644 > --- a/drivers/power/supply/bq24190_charger.c > +++ b/drivers/power/supply/bq24190_charger.c > @@ -1906,6 +1906,7 @@ static void bq24190_remove(struct i2c_client *client) > struct bq24190_dev_info *bdi = i2c_get_clientdata(client); > int error; > > + cancel_delayed_work_sync(&bdi->input_current_limit_work); > error = pm_runtime_resume_and_get(bdi->dev); > if (error < 0) > dev_warn(bdi->dev, "pm_runtime_get failed: %i\n", error); > -- > 2.25.1 >
Sebastian Reichel <sebastian.reichel@collabora.com> 于2023年3月10日周五 07:39写道： > > Hi, > > On Fri, Mar 10, 2023 at 02:10:36AM +0800, Zheng Wang wrote: > > 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 mtk_jpeg_remove > > mtk_jpeg_remove? Sorry that's mistake. I will correct it in the next version of patch. > > > > > 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> > > --- > > Looks correct to me, but the cancel_work_sync should happen after > usb_unregister_notifier(), otherwise there is still a race > condition. Yes, I agree that. Thanks for pointing that out. Will do in the next path. Best regards, Zheng > > > drivers/power/supply/da9150-charger.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/power/supply/da9150-charger.c b/drivers/power/supply/da9150-charger.c > > index 14da5c595dd9..41b68f2f6ed8 100644 > > --- a/drivers/power/supply/da9150-charger.c > > +++ b/drivers/power/supply/da9150-charger.c > > @@ -642,6 +642,7 @@ static int da9150_charger_remove(struct platform_device *pdev) > > struct da9150_charger *charger = platform_get_drvdata(pdev); > > int irq; > > > > + cancel_work_sync(&charger->otg_work); > > /* Make sure IRQs are released before unregistering power supplies */ > > irq = platform_get_irq_byname(pdev, "CHG_VBUS"); > > free_irq(irq, charger); > > -- > > 2.25.1 > >
Sebastian Reichel <sebastian.reichel@collabora.com> 于2023年3月10日周五 07:40写道： > > Hi, > > On Fri, Mar 10, 2023 at 01:47:28AM +0800, Zheng Wang wrote: > > In bq24190_probe, &bdi->input_current_limit_work is bound > > with bq24190_input_current_limit_work. When external power > > changed, it will call bq24190_charger_external_power_changed > > to start the work. > > > > If we remove the module which will call bq24190_remove to make > > cleanup, there may be a unfinished work. The possible > > sequence is as follows: > > > > CPU0 CPUc1 > > > > |bq24190_input_current_limit_work > > bq24190_remove | > > power_supply_unregister | > > device_unregister | > > power_supply_dev_release| > > kfree(psy) | > > | > > | power_supply_get_property_from_supplier > > | //use > > > > Fix it by finishing the work before cleanup in the bq24190_remove > > > > Fixes: 97774672573a ("power_supply: Initialize changed_work before calling device_add") > > Signed-off-by: Zheng Wang <zyytlz.wz@163.com> > > --- > > Thanks, queued to fixes branch. > Very glad to hear that. Thanks for your effort. Best regards, Zheng > > > drivers/power/supply/bq24190_charger.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/power/supply/bq24190_charger.c b/drivers/power/supply/bq24190_charger.c > > index be34b9848450..de67b985f0a9 100644 > > --- a/drivers/power/supply/bq24190_charger.c > > +++ b/drivers/power/supply/bq24190_charger.c > > @@ -1906,6 +1906,7 @@ static void bq24190_remove(struct i2c_client *client) > > struct bq24190_dev_info *bdi = i2c_get_clientdata(client); > > int error; > > > > + cancel_delayed_work_sync(&bdi->input_current_limit_work); > > error = pm_runtime_resume_and_get(bdi->dev); > > if (error < 0) > > dev_warn(bdi->dev, "pm_runtime_get failed: %i\n", error); > > -- > > 2.25.1 > >
diff --git a/drivers/power/supply/bq24190_charger.c b/drivers/power/supply/bq24190_charger.c index be34b9848450..de67b985f0a9 100644 --- a/drivers/power/supply/bq24190_charger.c +++ b/drivers/power/supply/bq24190_charger.c @@ -1906,6 +1906,7 @@ static void bq24190_remove(struct i2c_client *client) struct bq24190_dev_info *bdi = i2c_get_clientdata(client); int error; + cancel_delayed_work_sync(&bdi->input_current_limit_work); error = pm_runtime_resume_and_get(bdi->dev); if (error < 0) dev_warn(bdi->dev, "pm_runtime_get failed: %i\n", error);
In bq24190_probe, &bdi->input_current_limit_work is bound with bq24190_input_current_limit_work. When external power changed, it will call bq24190_charger_external_power_changed to start the work. If we remove the module which will call bq24190_remove to make cleanup, there may be a unfinished work. The possible sequence is as follows: CPU0 CPUc1 |bq24190_input_current_limit_work bq24190_remove | power_supply_unregister | device_unregister | power_supply_dev_release| kfree(psy) | | | power_supply_get_property_from_supplier | //use Fix it by finishing the work before cleanup in the bq24190_remove Fixes: 97774672573a ("power_supply: Initialize changed_work before calling device_add") Signed-off-by: Zheng Wang <zyytlz.wz@163.com> --- drivers/power/supply/bq24190_charger.c | 1 + 1 file changed, 1 insertion(+)