From: Adam Ford <aford173@xxxxxxxxx> [ 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 <aford173@xxxxxxxxx> Reviewed-by: Yegor Yefremov <yegorslists@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20191006163314.23191-1-aford173@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 42e42e3e7a6e6..388f710468490 100644 --- a/drivers/tty/serial/serial_mctrl_gpio.c +++ b/drivers/tty/serial/serial_mctrl_gpio.c @@ -69,6 +69,9 @@ 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); -- 2.20.1
