--- x/net/core/rtnetlink.c
+++ y/net/core/rtnetlink.c
@@ -3466,6 +3466,11 @@ static int rtnl_newlink_create(struct sk
 	}
 
 	dev->ifindex = ifm->ifi_index;
+	if (dev->ifindex > INT_MAX) {
+		err = -EINVAL;
+		free_netdev(dev);
+		goto out;
+	}
 
 	if (ops->newlink)
 		err = ops->newlink(link_net ? : net, dev, tb, data, extack);