Re: [PATCH v2] iio: hmc5843: fix potential NULL pointer dereferences

[Jonathan Cameron]

On Sat, 16 Mar 2019 17:08:33 -0500
Kangjie Lu <kjlu@xxxxxxx> wrote:

> devm_regmap_init_i2c may fail and return NULL. The fix returns
> the error when it fails.
> 
> Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
Applied to the togreg branch of iio.git and pushed out as testing
for the autobuilders to play with it.
Thanks.

Jonathan

> ---
> V2: fix the two together
> ---
>  drivers/iio/magnetometer/hmc5843_i2c.c | 7 ++++++-
>  drivers/iio/magnetometer/hmc5843_spi.c | 7 ++++++-
>  2 files changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/magnetometer/hmc5843_i2c.c b/drivers/iio/magnetometer/hmc5843_i2c.c
> index 3de7f4426ac4..86abba5827a2 100644
> --- a/drivers/iio/magnetometer/hmc5843_i2c.c
> +++ b/drivers/iio/magnetometer/hmc5843_i2c.c
> @@ -58,8 +58,13 @@ static const struct regmap_config hmc5843_i2c_regmap_config = {
>  static int hmc5843_i2c_probe(struct i2c_client *cli,
>  			     const struct i2c_device_id *id)
>  {
> +	struct regmap *regmap = devm_regmap_init_i2c(cli,
> +			&hmc5843_i2c_regmap_config);
> +	if (IS_ERR(regmap))
> +		return PTR_ERR(regmap);
> +
>  	return hmc5843_common_probe(&cli->dev,
> -			devm_regmap_init_i2c(cli, &hmc5843_i2c_regmap_config),
> +			regmap,
>  			id->driver_data, id->name);
>  }
>  
> diff --git a/drivers/iio/magnetometer/hmc5843_spi.c b/drivers/iio/magnetometer/hmc5843_spi.c
> index 535f03a70d63..8355713651d4 100644
> --- a/drivers/iio/magnetometer/hmc5843_spi.c
> +++ b/drivers/iio/magnetometer/hmc5843_spi.c
> @@ -58,6 +58,7 @@ static const struct regmap_config hmc5843_spi_regmap_config = {
>  static int hmc5843_spi_probe(struct spi_device *spi)
>  {
>  	int ret;
> +	struct regmap *regmap;
>  	const struct spi_device_id *id = spi_get_device_id(spi);
>  
>  	spi->mode = SPI_MODE_3;
> @@ -67,8 +68,12 @@ static int hmc5843_spi_probe(struct spi_device *spi)
>  	if (ret)
>  		return ret;
>  
> +	regmap = devm_regmap_init(spi, &hmc5843_spi_regmap_config);
> +	if (IS_ERR(regmap))
> +		return PTR_ERR(devm_regmap);
> +
>  	return hmc5843_common_probe(&spi->dev,
> -			devm_regmap_init_spi(spi, &hmc5843_spi_regmap_config),
> +			regmap,
>  			id->driver_data, id->name);
>  }
>