diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 22f60239026c..8a58ee32ff61 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -3076,6 +3076,10 @@ static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
 		dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
 		return NULL;
 	}
+	if (id >= ARRAY_SIZE(sci_ports)) {
+		dev_err(&pdev->dev, "serial%d out of range\n", id);
+		return NULL;
+	}
 
 	sp = &sci_ports[id];
 	*dev_id = id;