Re: [PATCH v2 3/5] HID: dualsense_remove: manually unregister leds
From: Benjamin Tissoires <hidden>
Date: 2023-02-09 09:00:41
Also in:
linux-leds, lkml
On Jan 31 2023, Pietro Borrello wrote:
Unregister the LED controllers before device removal, to prevent
unnecessary runs of dualsense_player_led_set_brightness().
Fixes: 8c0ab553b072 ("HID: playstation: expose DualSense player LEDs through LED class.")
Signed-off-by: Pietro Borrello <redacted>
---
Contrary to the other patches in this series, failing to unregister
the led controller does not results into a use-after-free thanks
to the output_worker_initialized variable and the spinlock checks.And so we don't need that patch (nor for hid-sony.c) because we have a guard against scheduling a worker job when the device is being removed. So please drop 3,4,5 from this series, they are just making the code worse. Cheers, Benjamin
quoted hunk ↗ jump to hunk
Changes in v2: - Unregister multicolor led controller - Clarify UAF - Link to v1: https://lore.kernel.org/all/20230125-hid-unregister-leds-v1-3-9a5192dcef16@diag.uniroma1.it/ (local) --- drivers/hid/hid-playstation.c | 6 ++++++ 1 file changed, 6 insertions(+)diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c index 27c40894acab..f23186ca2d76 100644 --- a/drivers/hid/hid-playstation.c +++ b/drivers/hid/hid-playstation.c@@ -1503,11 +1503,17 @@ static void dualsense_remove(struct ps_device *ps_dev) { struct dualsense *ds = container_of(ps_dev, struct dualsense, base); unsigned long flags; + int i; spin_lock_irqsave(&ds->base.lock, flags); ds->output_worker_initialized = false; spin_unlock_irqrestore(&ds->base.lock, flags); + for (i = 0; i < ARRAY_SIZE(ds->player_leds); i++) + devm_led_classdev_unregister(&ps_dev->hdev->dev, &ds->player_leds[i]); + + devm_led_classdev_multicolor_unregister(&ps_dev->hdev->dev, &ds->lightbar); + cancel_work_sync(&ds->output_worker); }-- 2.25.1