During appletb_kbd_probe, probe attempts to get the backlight device by name. When this happens backlight_device_get_by_name looks for a device in the backlight class which has name "appletb_backlight" and upon finding a match it increments the reference count for the device and returns it to the caller. However this reference is never released leading to a reference leak.

Fix this by decrementing the backlight device reference count on removal via put_device and on probe failure.

Fixes: 93a0fc489481 ("HID: hid-appletb-kbd: add support for automatic brightness control while using the touchbar") Cc: stable@vger.kernel.org Signed-off-by: Qasim Ijaz qasdev00@gmail.com --- drivers/hid/hid-appletb-kbd.c | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/drivers/hid/hid-appletb-kbd.c b/drivers/hid/hid-appletb-kbd.c index ef51b2c06872..e06567886e50 100644 --- a/drivers/hid/hid-appletb-kbd.c +++ b/drivers/hid/hid-appletb-kbd.c @@ -438,6 +438,8 @@ static int appletb_kbd_probe(struct hid_device *hdev, const struct hid_device_id return 0;

close_hw: + if (kbd->backlight_dev) + put_device(&kbd->backlight_dev->dev); hid_hw_close(hdev); stop_hw: hid_hw_stop(hdev); @@ -453,6 +455,9 @@ static void appletb_kbd_remove(struct hid_device *hdev) input_unregister_handler(&kbd->inp_handler); timer_delete_sync(&kbd->inactivity_timer);

+ if (kbd->backlight_dev) + put_device(&kbd->backlight_dev->dev); + hid_hw_close(hdev); hid_hw_stop(hdev); }