Re: [PATCH 2/2] mfd: mc13xxx: fix a possible NULL dereference

[Lee Jones]

On Tue, 16 Aug 2016, LABBE Corentin wrote:

> of_match_device could return NULL, and so cause a NULL pointer
> dereference later.
> For fixing this problem, we use of_device_get_match_data(), this will
> simplify the code a little by using a standard function for
> getting the match data.
> 
> Reported-by: coverity (CID 986513)
> Reported-by: coverity (CID 986514)
> Signed-off-by: LABBE Corentin <clabbe.montjoie@xxxxxxxxx>

Can you change your name to be "[A-Z][a-z]*"?

> ---
>  drivers/mfd/mc13xxx-i2c.c | 4 +---
>  drivers/mfd/mc13xxx-spi.c | 5 +----
>  2 files changed, 2 insertions(+), 7 deletions(-)

For the patch:
  Acked-by: Lee Jones <lee.jones@xxxxxxxxxx>
  
> diff --git a/drivers/mfd/mc13xxx-i2c.c b/drivers/mfd/mc13xxx-i2c.c
> index 3c00ccb..8ad7593 100644
> --- a/drivers/mfd/mc13xxx-i2c.c
> +++ b/drivers/mfd/mc13xxx-i2c.c
> @@ -78,9 +78,7 @@ static int mc13xxx_i2c_probe(struct i2c_client *client,
>  	}
>  
>  	if (client->dev.of_node) {
> -		const struct of_device_id *of_id =
> -			of_match_device(mc13xxx_dt_ids, &client->dev);
> -		mc13xxx->variant = of_id->data;
> +		mc13xxx->variant = of_device_get_match_data(&client->dev);
>  	} else {
>  		mc13xxx->variant = (const struct mc13xxx_variant *)id->driver_data;
>  	}
> diff --git a/drivers/mfd/mc13xxx-spi.c b/drivers/mfd/mc13xxx-spi.c
> index 6100025..3b4f5ba 100644
> --- a/drivers/mfd/mc13xxx-spi.c
> +++ b/drivers/mfd/mc13xxx-spi.c
> @@ -155,10 +155,7 @@ static int mc13xxx_spi_probe(struct spi_device *spi)
>  	}
>  
>  	if (spi->dev.of_node) {
> -		const struct of_device_id *of_id =
> -			of_match_device(mc13xxx_dt_ids, &spi->dev);
> -
> -		mc13xxx->variant = of_id->data;
> +		mc13xxx->variant = of_device_get_match_data(&spi->dev);
>  	} else {
>  		const struct spi_device_id *id_entry = spi_get_device_id(spi);
>  

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog