From 315c537068a13f0b5681d33dd045a912f4bece6f Mon Sep 17 00:00:00 2001 From: Pietro Borrello Date: Sun, 12 Feb 2023 19:00:02 +0000 Subject: HID: asus: use spinlock to protect concurrent accesses asus driver has a worker that may access data concurrently. Proct the accesses using a spinlock. Fixes: af22a610bc38 ("HID: asus: support backlight on USB keyboards") Signed-off-by: Pietro Borrello Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-4-7860c5763c38@diag.uniroma1.it Signed-off-by: Benjamin Tissoires --- drivers/hid/hid-asus.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) (limited to 'drivers/hid') diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c index f99752b998f3..9f767baf39fb 100644 --- a/drivers/hid/hid-asus.c +++ b/drivers/hid/hid-asus.c @@ -98,6 +98,7 @@ struct asus_kbd_leds { struct hid_device *hdev; struct work_struct work; unsigned int brightness; + spinlock_t lock; bool removed; }; @@ -495,7 +496,12 @@ static void asus_kbd_backlight_set(struct led_classdev *led_cdev, { struct asus_kbd_leds *led = container_of(led_cdev, struct asus_kbd_leds, cdev); + unsigned long flags; + + spin_lock_irqsave(&led->lock, flags); led->brightness = brightness; + spin_unlock_irqrestore(&led->lock, flags); + schedule_work(&led->work); } @@ -503,8 +509,14 @@ static enum led_brightness asus_kbd_backlight_get(struct led_classdev *led_cdev) { struct asus_kbd_leds *led = container_of(led_cdev, struct asus_kbd_leds, cdev); + enum led_brightness brightness; + unsigned long flags; - return led->brightness; + spin_lock_irqsave(&led->lock, flags); + brightness = led->brightness; + spin_unlock_irqrestore(&led->lock, flags); + + return brightness; } static void asus_kbd_backlight_work(struct work_struct *work) @@ -512,11 +524,14 @@ static void asus_kbd_backlight_work(struct work_struct *work) struct asus_kbd_leds *led = container_of(work, struct asus_kbd_leds, work); u8 buf[] = { FEATURE_KBD_REPORT_ID, 0xba, 0xc5, 0xc4, 0x00 }; 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); ret = asus_kbd_set_report(led->hdev, buf, sizeof(buf)); if (ret < 0) @@ -584,6 +599,7 @@ static int asus_kbd_register_leds(struct hid_device *hdev) drvdata->kbd_backlight->cdev.brightness_set = asus_kbd_backlight_set; drvdata->kbd_backlight->cdev.brightness_get = asus_kbd_backlight_get; INIT_WORK(&drvdata->kbd_backlight->work, asus_kbd_backlight_work); + spin_lock_init(&drvdata->kbd_backlight->lock); ret = devm_led_classdev_register(&hdev->dev, &drvdata->kbd_backlight->cdev); if (ret < 0) { @@ -1119,9 +1135,13 @@ err_stop_hw: static void asus_remove(struct hid_device *hdev) { struct asus_drvdata *drvdata = hid_get_drvdata(hdev); + unsigned long flags; if (drvdata->kbd_backlight) { + spin_lock_irqsave(&drvdata->kbd_backlight->lock, flags); drvdata->kbd_backlight->removed = true; + spin_unlock_irqrestore(&drvdata->kbd_backlight->lock, flags); + cancel_work_sync(&drvdata->kbd_backlight->work); } -- cgit v1.2.3 From 4ab3a086d10eeec1424f2e8a968827a6336203df Mon Sep 17 00:00:00 2001 From: Pietro Borrello Date: Sun, 12 Feb 2023 19:00:03 +0000 Subject: 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(-) (limited to 'drivers/hid') 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); -- cgit v1.2.3