From: Pietro Borrello <borrello@diag.uniroma1.it>

Date: Sun, 12 Feb 2023 19:00:02 +0000

Subject: [PATCH] HID: asus: use spinlock to protect concurrent accesses

References: bsc#1012628

Patch-mainline: 6.2.3

Git-commit: 315c537068a13f0b5681d33dd045a912f4bece6f

commit 315c537068a13f0b5681d33dd045a912f4bece6f upstream.

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 <borrello@diag.uniroma1.it>

Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-4-7860c5763c38@diag.uniroma1.it

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Signed-off-by: Stefan Ghinea <stefan.ghinea@windriver.com>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 drivers/hid/hid-asus.c | 22 +++++++++++++++++++++-

 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c

index f99752b9..9f767baf 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 @@ static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)

 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);

 	}

-- 

2.35.3