Re: [PATCH] iio: hmc5843_spi: fix a NULL pointer dereference

2019-03-10 Thread Jonathan Cameron
On Sat,  9 Mar 2019 12:56:27 -0600
Kangjie Lu  wrote:

> In case devm_regmap_init_spi fails and returns NULL, the fix
> returns an error to avoid NULL pointer dereference
> 
> Signed-off-by: Kangjie Lu 

Hi.

The fix is good, but please do the same for the i2c element of
the driver. I'd like them both in a single patch as it's exactly
the same issue in the same driver.

Minor comment inline on how I think it could be a tiny bit
nicer.

Thanks,

Jonathan

> ---
>  drivers/iio/magnetometer/hmc5843_spi.c | 8 +++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/magnetometer/hmc5843_spi.c 
> b/drivers/iio/magnetometer/hmc5843_spi.c
> index 535f03a70d63..15e2f7cbb3b5 100644
> --- a/drivers/iio/magnetometer/hmc5843_spi.c
> +++ b/drivers/iio/magnetometer/hmc5843_spi.c
> @@ -59,6 +59,12 @@ static int hmc5843_spi_probe(struct spi_device *spi)
>  {
>   int ret;
>   const struct spi_device_id *id = spi_get_device_id(spi);
> + struct regmap *devm_regmap = devm_regmap_init_spi(spi,
> + _spi_regmap_config);
Split this into the variable instantiation and the assignment.
That will let you (I think) avoid the nasty alignement.
Also, no need to have the devm_ prefix on the variable name.

struct regmap *regmap;

regmap = devm_regmap_init(spi, _spi_regmap_config);

> +
> + if (IS_ERR(devm_regmap))
> + return PTR_ERR(devm_regmap);
> +
>  
>   spi->mode = SPI_MODE_3;
>   spi->max_speed_hz = 800;
> @@ -68,7 +74,7 @@ static int hmc5843_spi_probe(struct spi_device *spi)
>   return ret;
>  
>   return hmc5843_common_probe(>dev,
> - devm_regmap_init_spi(spi, _spi_regmap_config),
> + devm_regmap,
>   id->driver_data, id->name);
>  }
>  



[PATCH] iio: hmc5843_spi: fix a NULL pointer dereference

2019-03-09 Thread Kangjie Lu
In case devm_regmap_init_spi fails and returns NULL, the fix
returns an error to avoid NULL pointer dereference

Signed-off-by: Kangjie Lu 
---
 drivers/iio/magnetometer/hmc5843_spi.c | 8 +++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/magnetometer/hmc5843_spi.c 
b/drivers/iio/magnetometer/hmc5843_spi.c
index 535f03a70d63..15e2f7cbb3b5 100644
--- a/drivers/iio/magnetometer/hmc5843_spi.c
+++ b/drivers/iio/magnetometer/hmc5843_spi.c
@@ -59,6 +59,12 @@ static int hmc5843_spi_probe(struct spi_device *spi)
 {
int ret;
const struct spi_device_id *id = spi_get_device_id(spi);
+   struct regmap *devm_regmap = devm_regmap_init_spi(spi,
+   _spi_regmap_config);
+
+   if (IS_ERR(devm_regmap))
+   return PTR_ERR(devm_regmap);
+
 
spi->mode = SPI_MODE_3;
spi->max_speed_hz = 800;
@@ -68,7 +74,7 @@ static int hmc5843_spi_probe(struct spi_device *spi)
return ret;
 
return hmc5843_common_probe(>dev,
-   devm_regmap_init_spi(spi, _spi_regmap_config),
+   devm_regmap,
id->driver_data, id->name);
 }
 
-- 
2.17.1