diff --git a/tools/lkl/fs2tar.c b/tools/lkl/fs2tar.c
index de769ee048b260..d10fa0303bda16 100644
--- a/tools/lkl/fs2tar.c
+++ b/tools/lkl/fs2tar.c
@@ -70,6 +70,7 @@ static error_t parse_opt(int key, char *arg, struct argp_state *state)
 	case ARGP_KEY_END:
 		if (state->arg_num < 2 || !cla->fsimg_type)
 			argp_usage(state);
+		break;
 	default:
 		return ARGP_ERR_UNKNOWN;
 	}
diff --git a/tools/lkl/lib/posix-host.c b/tools/lkl/lib/posix-host.c
index db63ed7e35fb19..f1ae3a2e6dbb37 100644
--- a/tools/lkl/lib/posix-host.c
+++ b/tools/lkl/lib/posix-host.c
@@ -186,7 +186,7 @@ static void mutex_free(struct lkl_mutex *_mutex)
 static lkl_thread_t thread_create(void (*fn)(void *), void *arg)
 {
 	pthread_t thread;
-	if (WARN_PTHREAD(pthread_create(&thread, NULL, (void* (*)(void *))fn, arg)))
+	if (WARN_PTHREAD(pthread_create(&thread, NULL, (void *)fn, arg)))
 		return 0;
 	else
 		return (lkl_thread_t) thread;
@@ -267,7 +267,7 @@ static void *timer_alloc(void (*fn)(void *), void *arg)
 		.sigev_value = {
 			.sival_ptr = arg,
 		},
-		.sigev_notify_function = (void (*)(union sigval))fn,
+		.sigev_notify_function = (void (*)())fn,
 	};
 
 	err = timer_create(CLOCK_REALTIME, &se, &timer);
diff --git a/tools/lkl/lib/virtio_net_tap.c b/tools/lkl/lib/virtio_net_tap.c
index e5302a375aeef8..b8ad42b5890a3a 100644
--- a/tools/lkl/lib/virtio_net_tap.c
+++ b/tools/lkl/lib/virtio_net_tap.c
@@ -104,7 +104,7 @@ struct lkl_netdev *lkl_netdev_tap_create(const char *ifname, int offload)
 #endif
 	};
 
-	strncpy(ifr.ifr_name, ifname, IFNAMSIZ);
+	snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s", ifname);
 
 	return lkl_netdev_tap_init(path, offload, &ifr);
 }