[PATCH][next] net: spider_net: Use size_add() in call to struct_size()

[Kees Cook]

On Fri, Sep 15, 2023 at 01:25:36PM -0600, Gustavo A. R. Silva wrote:
> If, for any reason, the open-coded arithmetic causes a wraparound,
> the protection that `struct_size()` adds against potential integer
> overflows is defeated. Fix this by hardening call to `struct_size()`
> with `size_add()`.
> 
> Fixes: 3f1071ec39f7 ("net: spider_net: Use struct_size() helper")
> Signed-off-by: Gustavo A. R. Silva <gustavoars at kernel.org>

Reviewed-by: Kees Cook <keescook at chromium.org>

-- 
Kees Cook