From 5290a8f6585b310cb55e393b4f6674f2347de408 Mon Sep 17 00:00:00 2001 From: Adam Ford Date: Sun, 6 Oct 2019 11:33:11 -0500 Subject: [PATCH] serial: mctrl_gpio: Check for NULL pointer [ Upstream commit 37e3ab00e4734acc15d96b2926aab55c894f4d9c ] When using mctrl_gpio_to_gpiod, it dereferences gpios into a single requested GPIO. This dereferencing can break if gpios is NULL, so this patch adds a NULL check before dereferencing it. If gpios is NULL, this function will also return NULL. Signed-off-by: Adam Ford Reviewed-by: Yegor Yefremov Link: https://lore.kernel.org/r/20191006163314.23191-1-aford173@gmail.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/serial_mctrl_gpio.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/tty/serial/serial_mctrl_gpio.c b/drivers/tty/serial/serial_mctrl_gpio.c index 02147361eaa9..2b5329a3d716 100644 --- a/drivers/tty/serial/serial_mctrl_gpio.c +++ b/drivers/tty/serial/serial_mctrl_gpio.c @@ -67,6 +67,9 @@ EXPORT_SYMBOL_GPL(mctrl_gpio_set); struct gpio_desc *mctrl_gpio_to_gpiod(struct mctrl_gpios *gpios, enum mctrl_gpio_idx gidx) { + if (gpios == NULL) + return NULL; + return gpios->gpio[gidx]; } EXPORT_SYMBOL_GPL(mctrl_gpio_to_gpiod);