Re: [PATCH net-next] mlxsw: spectrum_nve: Use struct_size() in kzalloc()

From: Ido Schimmel
Date: Wed Jan 16 2019 - 02:13:34 EST


On Tue, Jan 15, 2019 at 05:14:29PM -0600, Gustavo A. R. Silva wrote:
> One of the more common cases of allocation size calculations is finding
> the size of a structure that has a zero-sized array at the end, along
> with memory for some number of elements for that array. For example:
>
> struct foo {
> int stuff;
> struct boo entry[];
> };
>
> instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);
>
> Instead of leaving these open-coded and prone to type mistakes, we can
> now use the new struct_size() helper:
>
> instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
>
> This issue was detected with the help of Coccinelle.
>
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>

Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxxxx>