Re: [PATCH 3/3][next] scsi: smartpqi: Use struct_size() helper in pqi_report_phys_luns()

From: Kees Cook
Date: Thu Feb 02 2023 - 15:29:19 EST


On Wed, Sep 21, 2022 at 11:30:47PM -0500, Gustavo A. R. Silva wrote:
> Prefer struct_size() over open-coded versions of idiom:
>
> sizeof(struct-with-flex-array) + sizeof(typeof-flex-array-elements) * count
>
> where count is the max number of items the flexible array is supposed to
> contain.
>
> Link: https://github.com/KSPP/linux/issues/160
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

> ---
> drivers/scsi/smartpqi/smartpqi_init.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
> index 544cd18a90d7..17bdc8b3f161 100644
> --- a/drivers/scsi/smartpqi/smartpqi_init.c
> +++ b/drivers/scsi/smartpqi/smartpqi_init.c
> @@ -1192,7 +1192,7 @@ static inline int pqi_report_phys_luns(struct pqi_ctrl_info *ctrl_info, void **b
>
> rpl_8byte_wwid_list = rpl_list;
> num_physicals = get_unaligned_be32(&rpl_8byte_wwid_list->header.list_length) / sizeof(rpl_8byte_wwid_list->lun_entries[0]);
> - rpl_16byte_wwid_list_length = sizeof(struct report_lun_header) + (num_physicals * sizeof(struct report_phys_lun_16byte_wwid));
> + rpl_16byte_wwid_list_length = struct_size(rpl_16byte_wwid_list, lun_entries, num_physicals);
>
> rpl_16byte_wwid_list = kmalloc(rpl_16byte_wwid_list_length, GFP_KERNEL);
> if (!rpl_16byte_wwid_list)
> --
> 2.34.1
>

--
Kees Cook