[PATCH 4/9] serial: mxs-auart: Fix out-of-bounds access through DT alias

[Geert Uytterhoeven <geert+renesas@glider.be>]

The auart_port[] array is indexed using a value derived from the
"serialN" alias in DT, which may lead to an out-of-bounds access.

Fix this by adding a range check.

Fixes: cabf23e7aa00b145 ("serial: mxs-auart: Fix out-of-bounds access through DT alias")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/tty/serial/mxs-auart.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index 079dc47aa142d8e1..7ec1298512facfc8 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -1663,6 +1663,10 @@ static int mxs_auart_probe(struct platform_device *pdev)
 		s->port.line = pdev->id < 0 ? 0 : pdev->id;
 	else if (ret < 0)
 		return ret;
+	if (s->port.line >= MXS_AUART_PORTS) {
+		dev_err(&pdev->dev, "serial%d out of range\n", s->port.line);
+		return -EINVAL;
+	}
 
 	if (of_id) {
 		pdev->id_entry = of_id->data;
-- 
2.7.4