From 4ab3a086d10eeec1424f2e8a968827a6336203df Mon Sep 17 00:00:00 2001 From: Pietro Borrello Date: Sun, 12 Feb 2023 19:00:03 +0000 Subject: [PATCH] HID: asus: use spinlock to safely schedule workers Use spinlocks to deal with workers introducing a wrapper asus_schedule_work(), and several spinlock checks. Otherwise, asus_kbd_backlight_set() may schedule led->work after the structure has been freed, causing a use-after-free. Fixes: af22a610bc38 ("HID: asus: support backlight on USB keyboards") Signed-off-by: Pietro Borrello Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-5-7860c5763c38@diag.uniroma1.it Signed-off-by: Benjamin Tissoires --- drivers/hid/hid-asus.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c index 9f767ba..d1094bb 100644 --- a/drivers/hid/hid-asus.c +++ b/drivers/hid/hid-asus.c @@ -491,6 +491,16 @@ static int rog_nkey_led_init(struct hid_device *hdev) return ret; } +static void asus_schedule_work(struct asus_kbd_leds *led) +{ + unsigned long flags; + + spin_lock_irqsave(&led->lock, flags); + if (!led->removed) + schedule_work(&led->work); + spin_unlock_irqrestore(&led->lock, flags); +} + static void asus_kbd_backlight_set(struct led_classdev *led_cdev, enum led_brightness brightness) { @@ -502,7 +512,7 @@ static void asus_kbd_backlight_set(struct led_classdev *led_cdev, led->brightness = brightness; spin_unlock_irqrestore(&led->lock, flags); - schedule_work(&led->work); + asus_schedule_work(led); } static enum led_brightness asus_kbd_backlight_get(struct led_classdev *led_cdev) @@ -526,9 +536,6 @@ static void asus_kbd_backlight_work(struct work_struct *work) int ret; unsigned long flags; - if (led->removed) - return; - spin_lock_irqsave(&led->lock, flags); buf[4] = led->brightness; spin_unlock_irqrestore(&led->lock, flags); -- 2.7.4