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 for linux-mtd@lists.infradead.org; Fri, 20 Nov 2015 08:33:40 +0000
Subject: Re: [PATCH v2 2/2] mtd: nand: atmel_nand: fix a possible NULL
 dereference
To: LABBE Corentin <clabbe.montjoie@gmail.com>, <computersforpeace@gmail.com>,
 <dwmw2@infradead.org>
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From: Josh Wu <josh.wu@atmel.com>
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Date: Fri, 20 Nov 2015 16:33:14 +0800
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Hi, Corentin

Thanks for the patch. It looks fine to me, just one nitpick in below:

On 11/20/2015 3:45 PM, LABBE Corentin 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 | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
> index 475c938..7902967 100644
> --- a/drivers/mtd/nand/atmel_nand.c
> +++ b/drivers/mtd/nand/atmel_nand.c
> @@ -1496,8 +1496,9 @@ static int atmel_of_init_port(struct atmel_nand_host *host,
>   	struct atmel_nand_data *board = &host->board;
>   	enum of_gpio_flags flags = 0;
>   
> -	host->caps = (struct atmel_nand_caps *)
> -		of_match_device(atmel_nand_dt_ids, host->dev)->data;
> +	host->caps = of_device_get_match_data(host->dev);
> +	if (!host->caps)
> +		return 1;

it's better to use -EINVAL here.

Best Regards,
Josh Wu

>   
>   	if (of_property_read_u32(np, "atmel,nand-addr-offset", &val) == 0) {
>   		if (val >= 32) {