Re: [PATCH][next] IB/hfi1: Use struct_size() helper

[Dennis Dalessandro]

On 5/29/2019 11:15 AM, Gustavo A. R. Silva wrote:
> Make use of the struct_size() helper instead of an open-coded version
> in order to avoid any potential type mistakes, in particular in the
> context in which this code is being used.
>
> So, replace the following form:
>
> sizeof(struct opa_port_status_rsp) + num_vls * sizeof(struct _vls_pctrs)
>
> with:
>
> struct_size(rsp, vls, num_vls)
>
> and so on...
>
> Also, notice that variable size is unnecessary, hence it is removed.
>
> This code was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
> ---
>   drivers/infiniband/hw/hfi1/mad.c | 9 +++------
>   1 file changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/infiniband/hw/hfi1/mad.c b/drivers/infiniband/hw/hfi1/mad.c
> index 4228393e6c4c..184dba3c2828 100644
> --- a/drivers/infiniband/hw/hfi1/mad.c
> +++ b/drivers/infiniband/hw/hfi1/mad.c
> @@ -2744,8 +2744,7 @@ static int pma_get_opa_portstatus(struct opa_pma_mad *pmp,
>   	u16 link_width;
>   	u16 link_speed;
>   
> -	response_data_size = sizeof(struct opa_port_status_rsp) +
> -				num_vls * sizeof(struct _vls_pctrs);
> +	response_data_size = struct_size(rsp, vls, num_vls);
>   	if (response_data_size > sizeof(pmp->data)) {
>   		pmp->mad_hdr.status |= OPA_PM_STATUS_REQUEST_TOO_LARGE;
>   		return reply((struct ib_mad_hdr *)pmp);
> @@ -3014,8 +3013,7 @@ static int pma_get_opa_datacounters(struct opa_pma_mad *pmp,
>   	}
>   
>   	/* Sanity check */
> -	response_data_size = sizeof(struct opa_port_data_counters_msg) +
> -				num_vls * sizeof(struct _vls_dctrs);
> +	response_data_size = struct_size(req, port[0].vls, num_vls);
>   
>   	if (response_data_size > sizeof(pmp->data)) {
>   		pmp->mad_hdr.status |= IB_SMP_INVALID_FIELD;
> @@ -3232,8 +3230,7 @@ static int pma_get_opa_porterrors(struct opa_pma_mad *pmp,
>   		return reply((struct ib_mad_hdr *)pmp);
>   	}
>   
> -	response_data_size = sizeof(struct opa_port_error_counters64_msg) +
> -				num_vls * sizeof(struct _vls_ectrs);
> +	response_data_size = struct_size(req, port[0].vls, num_vls);
>   
>   	if (response_data_size > sizeof(pmp->data)) {
>   		pmp->mad_hdr.status |= IB_SMP_INVALID_FIELD;

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>