Re: [PATCH] drivers/block/loop: Remove deprecated function, range check for max_loop

[Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>]

Thanks for your patch.

On 06/25/2019 04:47 AM, Florian Knauf wrote:
> This patch removes the deprecated simple_strtol function from the option
> parsing logic in the loopback device driver. It also introduces a range
> check for the max_loop parameter to ensure that negative and out-of-range
> values (that cannot be represented by int max_loop) are ignored.
>
> Signed-off-by: Florian Knauf <florian.knauf@stud.uni-hannover.de>
> Signed-off-by: Christian Ewert <christian.ewert@stud.uni-hannover.de>
> ---
>   drivers/block/loop.c | 12 +++++++++++-
>   1 file changed, 11 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/block/loop.c b/drivers/block/loop.c
> index 102d79575895..acdd028ed486 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -2289,7 +2289,17 @@ module_exit(loop_exit);
>   #ifndef MODULE
>   static int __init max_loop_setup(char *str)
>   {
> -	max_loop = simple_strtol(str, NULL, 0);
> +	long max_loop_long = 0;
> +
> +	/*
> +	 * Range check for max_loop: negative values and values not
> +	 * representable by int are ignored.
> +	 */
> +	if (kstrtol(str, 0, &max_loop_long) == 0 &&
Is there any specific reason to use kstrtol()?

Since max_loop global variable is defined as an int, can we use kstrtoint()?
> +			max_loop_long >= 0 &&
> +			max_loop_long <= INT_MAX)
> +		max_loop = (int) max_loop_long;
> +
>   	return 1;
>   }
>
>