Commit 090fa4b0 authored Feb 23, 2018 by Geert Uytterhoeven Committed by Greg Kroah-Hartman Feb 28, 2018

serial: sh-sci: Fix out-of-bounds access through DT alias



The sci_ports[] 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.

Note that the array size is defined by a Kconfig symbol
(CONFIG_SERIAL_SH_SCI_NR_UARTS), so this can even be triggered using a
legitimate DTB.

Fixes: 97ed9790 ("serial: sh-sci: Remove unused platform data capabilities field")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 49ee23b7

drivers/tty/serial/sh-sci.c

+4 −0

Original line number	Diff line number	Diff line
		@@ -3109,6 +3109,10 @@ 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;