[PATCH 4.19 087/134] serial: mvebu-uart: Fix to avoid a potential NULL pointer dereference

[Greg Kroah-Hartman]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aditya Pakki <pakki001@xxxxxxx>

commit 32f47179833b63de72427131169809065db6745e upstream.

of_match_device on failure to find a matching device can return a NULL
pointer. The patch checks for such a scenrio and passes the error upstream.

Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/tty/serial/mvebu-uart.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/tty/serial/mvebu-uart.c
+++ b/drivers/tty/serial/mvebu-uart.c
@@ -799,6 +799,9 @@ static int mvebu_uart_probe(struct platf
 		return -EINVAL;
 	}
 
+	if (!match)
+		return -ENODEV;
+
 	/* Assume that all UART ports have a DT alias or none has */
 	id = of_alias_get_id(pdev->dev.of_node, "serial");
 	if (!pdev->dev.of_node || id < 0)