Re: [PATCH] mfd: ene-kb3930: Fix potential NULL pointer dereference

[Lee Jones <lee@kernel.org>]

On Mon, 20 Jan 2025, Chenyuan Yang wrote:

> The off_gpios could be NULL. Add missing check in the kb3930_probe().
> This is similar to the issue fixed in commit
> b1ba8bcb2d1ffce11b308ce166c9cc28d989e3b9 ("backlight: hx8357:Fix potential NULL pointer dereference").
> 
> Fixes: ede6b2d1dfc0 ("mfd: ene-kb3930: Add driver for ENE KB3930 Embedded Controller")
> Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com>
> ---
>  drivers/mfd/ene-kb3930.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/mfd/ene-kb3930.c b/drivers/mfd/ene-kb3930.c
> index fa0ad2f14a39..60824d847bf0 100644
> --- a/drivers/mfd/ene-kb3930.c
> +++ b/drivers/mfd/ene-kb3930.c
> @@ -162,6 +162,8 @@ static int kb3930_probe(struct i2c_client *client)
>  			devm_gpiod_get_array_optional(dev, "off", GPIOD_IN);
>  		if (IS_ERR(ddata->off_gpios))
>  			return PTR_ERR(ddata->off_gpios);
> +		if (!ddata->off_gpios)
> +			return -ENOMEM;

I don't see many other call sites checking for NULL - why is this
different?

What about IS_ERR_OR_NULL() instead?

>  		if (ddata->off_gpios->ndescs < 2) {
>  			dev_err(dev, "invalid off-gpios property\n");
>  			return -EINVAL;
> -- 
> 2.34.1
> 

-- 
Lee Jones [李琼斯]