[PATCH 5.10 003/529] HID: asus: use spinlock to safely schedule workers

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Pietro Borrello <borrello@xxxxxxxxxxxxxxxx>

commit 4ab3a086d10eeec1424f2e8a968827a6336203df upstream.

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>
Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-5-7860c5763c38@xxxxxxxxxxxxxxxx
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Stefan Ghinea <stefan.ghinea@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/hid/hid-asus.c |   15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -398,6 +398,16 @@ static int asus_kbd_get_functions(struct
 	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)
 {
@@ -409,7 +419,7 @@ static void asus_kbd_backlight_set(struc
 	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)
@@ -433,9 +443,6 @@ static void asus_kbd_backlight_work(stru
 	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);





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux