diff --git a/sys/dev/uart/uart_tty.c b/sys/dev/uart/uart_tty.c
index 601c377042f..df3d9eb3fd2 100644
--- a/sys/dev/uart/uart_tty.c
+++ b/sys/dev/uart/uart_tty.c
@@ -137,6 +137,10 @@ uart_tty_open(struct tty *tp, struct cdev *dev)
 	struct uart_softc *sc;
 
 	sc = tp->t_sc;
+
+	if (sc == NULL || sc->sc_leaving)
+		return (ENXIO);
+
 	sc->sc_opened = 1;
 	return (0);
 }