[PATCH 2/2] gpio: stm32: check result of ofnode_phandle_args

[Patrice CHOTARD]

Hi Patrick

On 9/9/20 6:28 PM, Patrick Delaunay wrote:
> Add test on the size of ofnode_phandle_args result to avoid access
> to uninitialized elements in args[] field.
>
> This patch avoids the issue when gpio-ranges cell size is not 3 as
> expected, for example:
> 	gpio-ranges = <&pinctrl 0>;
> instead of
> 	gpio-ranges = <&pinctrl 0 112 16>;
>
> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> ---
>
>  drivers/gpio/stm32_gpio.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/gpio/stm32_gpio.c b/drivers/gpio/stm32_gpio.c
> index aa70b1d2a9..473e364796 100644
> --- a/drivers/gpio/stm32_gpio.c
> +++ b/drivers/gpio/stm32_gpio.c
> @@ -295,6 +295,9 @@ static int gpio_stm32_probe(struct udevice *dev)
>  	ret = dev_read_phandle_with_args(dev, "gpio-ranges",
>  					 NULL, 3, i, &args);
>  
> +	if (!ret && args.args_count < 3)
> +		return -EINVAL;
> +
>  	if (ret == -ENOENT) {
>  		uc_priv->gpio_count = STM32_GPIOS_PER_BANK;
>  		priv->gpio_range = GENMASK(STM32_GPIOS_PER_BANK - 1, 0);
> @@ -308,6 +311,8 @@ static int gpio_stm32_probe(struct udevice *dev)
>  
>  		ret = dev_read_phandle_with_args(dev, "gpio-ranges", NULL, 3,
>  						 ++i, &args);
> +		if (!ret && args.args_count < 3)
> +			return -EINVAL;
>  	}
>  
>  	dev_dbg(dev, "addr = 0x%p bank_name = %s gpio_count = %d gpio_range = 0x%x\n",

Reviewed-by: Patrice Chotard <patrice.chotard at st.com>

Thanks