[PATCH wireless-next] wifi: rt2x00: Allocate LED names dynamically

[Rosen Penev]

The rt2x00 LED registration path builds LED class names from the
driver and wiphy names. A fixed stack buffer can truncate those names
before they are passed to the LED core.

Allocate each LED name with kasprintf(), check allocation failures, and
release the stored name when the LED is unregistered.

Assisted-by: Codex:GPT-5.5
Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
---
 .../net/wireless/ralink/rt2x00/rt2x00leds.c   | 30 ++++++++++++++-----
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00leds.c b/drivers/net/wireless/ralink/rt2x00/rt2x00leds.c
index f5361d582d4e..8818e0b2447b 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00leds.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00leds.c
@@ -100,6 +100,8 @@ static int rt2x00leds_register_led(struct rt2x00_dev *rt2x00dev,
 
 	retval = led_classdev_register(device, &led->led_dev);
 	if (retval) {
+		kfree(name);
+		led->led_dev.name = NULL;
 		rt2x00_err(rt2x00dev, "Failed to register led handler\n");
 		return retval;
 	}
@@ -111,15 +113,19 @@ static int rt2x00leds_register_led(struct rt2x00_dev *rt2x00dev,
 
 void rt2x00leds_register(struct rt2x00_dev *rt2x00dev)
 {
-	char name[36];
+	char *name;
 	int retval;
 	unsigned long on_period;
 	unsigned long off_period;
 	const char *phy_name = wiphy_name(rt2x00dev->hw->wiphy);
 
 	if (rt2x00dev->led_radio.flags & LED_INITIALIZED) {
-		snprintf(name, sizeof(name), "%s-%s::radio",
-			 rt2x00dev->ops->name, phy_name);
+		name = kasprintf(GFP_KERNEL, "%s-%s::radio",
+				 rt2x00dev->ops->name, phy_name);
+		if (!name) {
+			retval = -ENOMEM;
+			goto exit_fail;
+		}
 
 		retval = rt2x00leds_register_led(rt2x00dev,
 						 &rt2x00dev->led_radio,
@@ -129,8 +135,12 @@ void rt2x00leds_register(struct rt2x00_dev *rt2x00dev)
 	}
 
 	if (rt2x00dev->led_assoc.flags & LED_INITIALIZED) {
-		snprintf(name, sizeof(name), "%s-%s::assoc",
-			 rt2x00dev->ops->name, phy_name);
+		name = kasprintf(GFP_KERNEL, "%s-%s::assoc",
+				 rt2x00dev->ops->name, phy_name);
+		if (!name) {
+			retval = -ENOMEM;
+			goto exit_fail;
+		}
 
 		retval = rt2x00leds_register_led(rt2x00dev,
 						 &rt2x00dev->led_assoc,
@@ -140,8 +150,12 @@ void rt2x00leds_register(struct rt2x00_dev *rt2x00dev)
 	}
 
 	if (rt2x00dev->led_qual.flags & LED_INITIALIZED) {
-		snprintf(name, sizeof(name), "%s-%s::quality",
-			 rt2x00dev->ops->name, phy_name);
+		name = kasprintf(GFP_KERNEL, "%s-%s::quality",
+				 rt2x00dev->ops->name, phy_name);
+		if (!name) {
+			retval = -ENOMEM;
+			goto exit_fail;
+		}
 
 		retval = rt2x00leds_register_led(rt2x00dev,
 						 &rt2x00dev->led_qual,
@@ -182,6 +196,8 @@ static void rt2x00leds_unregister_led(struct rt2x00_led *led)
 		led->led_dev.brightness_set(&led->led_dev, LED_OFF);
 
 	led->flags &= ~LED_REGISTERED;
+	kfree(led->led_dev.name);
+	led->led_dev.name = NULL;
 }
 
 void rt2x00leds_unregister(struct rt2x00_dev *rt2x00dev)
-- 
2.54.0