Re: [PATCH v2] mnt_idmapping: Use kmemdup_array instead of kmemdup for multiple allocation

[Jan Kara]

On Fri 23-08-24 09:55:41, Yu Jiaoliang wrote:
> Let the kememdup_array() take care about multiplication and possible
> overflows.
> 
> v2:Add a new modification for reverse array.
> 
> Signed-off-by: Yu Jiaoliang <yujiaoliang@xxxxxxxx>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

								Honza

> ---
>  fs/mnt_idmapping.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/mnt_idmapping.c b/fs/mnt_idmapping.c
> index 3c60f1eaca61..79491663dbc0 100644
> --- a/fs/mnt_idmapping.c
> +++ b/fs/mnt_idmapping.c
> @@ -228,15 +228,15 @@ static int copy_mnt_idmap(struct uid_gid_map *map_from,
>  		return 0;
>  	}
>  
> -	forward = kmemdup(map_from->forward,
> -			  nr_extents * sizeof(struct uid_gid_extent),
> -			  GFP_KERNEL_ACCOUNT);
> +	forward = kmemdup_array(map_from->forward, nr_extents,
> +				sizeof(struct uid_gid_extent),
> +				GFP_KERNEL_ACCOUNT);
>  	if (!forward)
>  		return -ENOMEM;
>  
> -	reverse = kmemdup(map_from->reverse,
> -			  nr_extents * sizeof(struct uid_gid_extent),
> -			  GFP_KERNEL_ACCOUNT);
> +	reverse = kmemdup_array(map_from->reverse, nr_extents,
> +				sizeof(struct uid_gid_extent),
> +				GFP_KERNEL_ACCOUNT);
>  	if (!reverse) {
>  		kfree(forward);
>  		return -ENOMEM;
> -- 
> 2.34.1
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR