linux-kernel - Re: [PATCH] iio: pressure: bmp280: Use IS_ERR_OR_NULL() in bmp280_common

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <b7288d5e-8dc8-4ee1-ae34-52904a3f989d@baylibre.com>
Date: Wed, 6 Aug 2025 20:24:37 -0500
From: David Lechner <dlechner@...libre.com>
To: Salah Triki <salah.triki@...il.com>, Jonathan Cameron <jic23@...nel.org>,
 Nuno Sá <nuno.sa@...log.com>,
 Andy Shevchenko <andy@...nel.org>, linux-iio@...r.kernel.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH] iio: pressure: bmp280: Use IS_ERR_OR_NULL() in
 bmp280_common_probe()

On 8/6/25 7:52 PM, Salah Triki wrote:
> `devm_gpiod_get_optional()` may return non-NULL error pointer on failure.
> Check its return value using `IS_ERR_OR_NULL()` and propagate the error if
> necessary.
> 
> Signed-off-by: Salah Triki <salah.triki@...il.com>
> ---
>  drivers/iio/pressure/bmp280-core.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
> index 74505c9ec1a0..2ac0188d2857 100644
> --- a/drivers/iio/pressure/bmp280-core.c
> +++ b/drivers/iio/pressure/bmp280-core.c
> @@ -3213,11 +3213,13 @@ int bmp280_common_probe(struct device *dev,
>  
>  	/* Bring chip out of reset if there is an assigned GPIO line */
>  	gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
> +

No blank line here.

> +	if (IS_ERR_OR_NULL(gpiod))

This needs to be IS_ERR(). NULL is not an error and we
cant return early here because there is more to do in
the probe function.

> +		return dev_err_probe(dev, PTR_ERR(gpiod), "failed to get GPIO\n");
> +
>  	/* Deassert the signal */
> -	if (gpiod) {
> -		dev_info(dev, "release reset\n");
> -		gpiod_set_value(gpiod, 0);
> -	}
> +	dev_info(dev, "release reset\n");
> +	gpiod_set_value(gpiod, 0);

If we drop the `if` here, we should also drop the
dev_info(). gpiod_set_value() handles NULL gpiod value
so that is fine, but the message is just noise.

Also, gpiod_set_value_cansleep() would be more
appropriate. This is not an atomic context.

>  
>  	data->regmap = regmap;
>