Re: [PATCH][next] NTB: Use struct_size() helper in devm_kzalloc()

[Logan Gunthorpe]

On 2020-06-19 11:25 a.m., 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. Also, remove unnecessary
> variable _struct_size_.
> 
> This code was detected with the help of Coccinelle and, audited and
> fixed manually.
> 
> Addresses-KSPP-ID: https://github.com/KSPP/linux/issues/83
> Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Cool, I didn't know that existed! Thanks!

Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>

> ---
>  drivers/ntb/test/ntb_msi_test.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/ntb/test/ntb_msi_test.c b/drivers/ntb/test/ntb_msi_test.c
> index 99d826ed9c34..7095ecd6223a 100644
> --- a/drivers/ntb/test/ntb_msi_test.c
> +++ b/drivers/ntb/test/ntb_msi_test.c
> @@ -319,7 +319,6 @@ static void ntb_msit_remove_dbgfs(struct ntb_msit_ctx *nm)
>  static int ntb_msit_probe(struct ntb_client *client, struct ntb_dev *ntb)
>  {
>  	struct ntb_msit_ctx *nm;
> -	size_t struct_size;
>  	int peers;
>  	int ret;
>  
> @@ -352,9 +351,7 @@ static int ntb_msit_probe(struct ntb_client *client, struct ntb_dev *ntb)
>  		return ret;
>  	}
>  
> -	struct_size = sizeof(*nm) + sizeof(*nm->peers) * peers;
> -
> -	nm = devm_kzalloc(&ntb->dev, struct_size, GFP_KERNEL);
> +	nm = devm_kzalloc(&ntb->dev, struct_size(nm, peers, peers), GFP_KERNEL);
>  	if (!nm)
>  		return -ENOMEM;
>  
>