[PATCH] mtd: nand: Prevent dereference of NULL pointer

[Andrew Goodbody]

ping?

On 01/07/2025 17:12, Andrew Goodbody wrote:
> In nand_wait_ready there is a loop that includes a NULL check for
> chip->dev_ready before it is dereferenced. Use a NULL check once the
> loop is exited as well to cover the case where it exits due to a timeout
> and it is therefore not known if chip->dev_ready is NULL or not.
> 
> This issue found by Smatch.
> 
> Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>
> ---
>   drivers/mtd/nand/raw/nand_base.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> index d3d1b93947b..48e3685d995 100644
> --- a/drivers/mtd/nand/raw/nand_base.c
> +++ b/drivers/mtd/nand/raw/nand_base.c
> @@ -566,7 +566,7 @@ void nand_wait_ready(struct mtd_info *mtd)
>   				break;
>   	}
>   
> -	if (!chip->dev_ready(mtd))
> +	if (!chip->dev_ready || !chip->dev_ready(mtd))
>   		pr_warn("timeout while waiting for chip to become ready\n");
>   }
>   EXPORT_SYMBOL_GPL(nand_wait_ready);
> 
> ---
> base-commit: 7027b445cc0bfb86204ecb1f1fe596f5895048d9
> change-id: 20250701-mtd_nand_fixes-191e5a19932d
> 
> Best regards,