Re: [PATCH] mtd: nand: atmel_nand: fix a possible NULL dereference

[Joachim Eastwood <manabian@gmail.com>]

On 12 November 2015 at 08:49, LABBE Corentin <clabbe.montjoie@gmail.com> wrote:
> of_match_device could return NULL, and so cause a NULL pointer
> dereference later.
>
> Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com>
> ---
>  drivers/mtd/nand/atmel_nand.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
> index 475c938..f3cf68b 100644
> --- a/drivers/mtd/nand/atmel_nand.c
> +++ b/drivers/mtd/nand/atmel_nand.c
> @@ -1495,9 +1495,12 @@ static int atmel_of_init_port(struct atmel_nand_host *host,
>         int ecc_mode;
>         struct atmel_nand_data *board = &host->board;
>         enum of_gpio_flags flags = 0;
> +       const struct of_device_id *of_id;
>
> -       host->caps = (struct atmel_nand_caps *)
> -               of_match_device(atmel_nand_dt_ids, host->dev)->data;
> +       of_id = of_match_device(atmel_nand_dt_ids, host->dev);
> +       if (!of_id)
> +               return -ENODEV;
> +       host->caps = of_id->data;

It might be cleaner to use of_device_get_match_data() here.


regards,
Joachim Eastwood