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 <borrello@xxxxxxxxxxxxxxxx>
---
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 9f767baf39fb..d1094bb1aa42 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);
--
2.25.1
