Re: [oss-drivers] [PATCH][next] nfp: flower: use struct_size() helper

On Wed, 5 Jun 2019 15:38:27 -0500, 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 nfp_tun_active_tuns {
	...
        struct route_ip_info {
                __be32 ipv4;
                __be32 egress_port;
                __be32 extra[2];
        } tun_info[];
};

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes.

So, replace the following form:

sizeof(struct nfp_tun_active_tuns) + sizeof(struct route_ip_info) * count

with:

struct_size(payload, tun_info, count)

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <redacted>

Acked-by: Jakub Kicinski <redacted>

Thanks!