Re: [PATCH] HID: wacom: fix crash in wacom_aes_battery_handler()

[Ping Cheng]

On Tue, Jun 10, 2025 at 12:21 PM Jiri Kosina <jikos@xxxxxxxxxx> wrote:
>
> On Mon, 19 May 2025, Thomas Zeitlhofer wrote:
>
> > Commit fd2a9b29dc9c ("HID: wacom: Remove AES power_supply after extended
> > inactivity") introduced wacom_aes_battery_handler() which is scheduled
> > as a delayed work (aes_battery_work).
> >
> > In wacom_remove(), aes_battery_work is not canceled. Consequently, if
> > the device is removed while aes_battery_work is still pending, then hard
> > crashes or "Oops: general protection fault..." are experienced when
> > wacom_aes_battery_handler() is finally called. E.g., this happens with
> > built-in USB devices after resume from hibernate when aes_battery_work
> > was still pending at the time of hibernation.
> >
> > So, take care to cancel aes_battery_work in wacom_remove().
> >
> > Fixes: fd2a9b29dc9c ("HID: wacom: Remove AES power_supply after extended inactivity")
> > Signed-off-by: Thomas Zeitlhofer <thomas.zeitlhofer+lkml@xxxxxxxx>

Acked-by: Ping Cheng <ping.cheng@xxxxxxxxx>

Thank you, Thomas, for the patch. Your support is greatly appreciated!

> This looks good to me, and I am planning to push it to Linus through
> for-6.16/upstream-fixes.
>
> Jason, Ping, any chance you could give your Ack to this one before I do
> so, please?

The patch looks reasonable to me, too. My Acked-by is added above.

Thank you, both of you!
Ping

>
> Thanks.
>
> > ---
> >  drivers/hid/wacom_sys.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> > index eaf099b2efdb..e74c1a4c5b61 100644
> > --- a/drivers/hid/wacom_sys.c
> > +++ b/drivers/hid/wacom_sys.c
> > @@ -2901,6 +2901,7 @@ static void wacom_remove(struct hid_device *hdev)
> >       hid_hw_stop(hdev);
> >
> >       cancel_delayed_work_sync(&wacom->init_work);
> > +     cancel_delayed_work_sync(&wacom->aes_battery_work);
> >       cancel_work_sync(&wacom->wireless_work);
> >       cancel_work_sync(&wacom->battery_work);
> >       cancel_work_sync(&wacom->remote_work);
> > --
> > 2.39.5
> >
>
> --
> Jiri Kosina
> SUSE Labs
>
>