arcnet: Add NULL check in com20020pci_probe()

devm_kasprintf() returns NULL when memory allocation fails. Currently,
com20020pci_probe() does not check for this case, which results in a
NULL pointer dereference.

Add NULL check after devm_kasprintf() to prevent this issue and ensure
no resources are left allocated.

Fixes: 6b17a59 ("arcnet: restoring support for multiple Sohard Arcnet cards")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
Link: https://patch.msgid.link/20250402135036.44697-1-bsdhenrymartin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/arcnet/com20020-pci.c

@@ -251,18 +251,33 @@ static int com20020pci_probe(struct pci_dev *pdev,
 			card->tx_led.default_trigger = devm_kasprintf(&pdev->dev,
 							GFP_KERNEL, "arc%d-%d-tx",
 							dev->dev_id, i);
+			if (!card->tx_led.default_trigger) {
+				ret = -ENOMEM;
+				goto err_free_arcdev;
+			}
 			card->tx_led.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 							"pci:green:tx:%d-%d",
 							dev->dev_id, i);
-
+			if (!card->tx_led.name) {
+				ret = -ENOMEM;
+				goto err_free_arcdev;
+			}
 			card->tx_led.dev = &dev->dev;
 			card->recon_led.brightness_set = led_recon_set;
 			card->recon_led.default_trigger = devm_kasprintf(&pdev->dev,
 							GFP_KERNEL, "arc%d-%d-recon",
 							dev->dev_id, i);
+			if (!card->recon_led.default_trigger) {
+				ret = -ENOMEM;
+				goto err_free_arcdev;
+			}
 			card->recon_led.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
 							"pci:red:recon:%d-%d",
 							dev->dev_id, i);
+			if (!card->recon_led.name) {
+				ret = -ENOMEM;
+				goto err_free_arcdev;
+			}
 			card->recon_led.dev = &dev->dev;
 
 			ret = devm_led_classdev_register(&pdev->dev, &card->tx_led);