[PATCH v2 6/9] serial: samsung: Fix out-of-bounds access through serial port index
From: geert+renesas@glider.be (Geert Uytterhoeven)
Date: 2018-02-23 13:39:25
Also in:
linux-devicetree, linux-renesas-soc, linux-serial, lkml
Subsystem:
arm/samsung s3c, s5p and exynos arm architectures, the rest, tty layer and serial drivers · Maintainers:
Krzysztof Kozlowski, Peter Griffin, Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
The s3c24xx_serial_ports[] array is indexed using a value derived from
the "serialN" alias in DT, or from an incrementing probe index, 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_SAMSUNG_UARTS), so this can even be triggered using
a legitimate DTB or legitimate board code.
Fixes: 13a9f6c64fdc55eb ("serial: samsung: Consider DT alias when probing ports")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v2:
- Fix Fixes reference,
- Use ARRAY_SIZE(),
- Update patch description for non-DT case.
---
drivers/tty/serial/samsung.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index f9fecc5ed0cee826..3f2f8c118ce09d56 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c@@ -1818,6 +1818,10 @@ static int s3c24xx_serial_probe(struct platform_device *pdev) dbg("s3c24xx_serial_probe(%p) %d\n", pdev, index); + if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) { + dev_err(&pdev->dev, "serial%d out of range\n", index); + return -EINVAL; + } ourport = &s3c24xx_serial_ports[index]; ourport->drv_data = s3c24xx_get_driver_data(pdev);
--
2.7.4