Re: [PATCH gwproxy v1 3/3] dnslookup: Initial work for implementation of C-ares-like getaddrinfo function

[Alviro Iskandar Setiawan <alviro.iskandar@gnuweeb.org>]

On Thu, Jul 31, 2025 at 10:09 AM Ahmad Gani wrote:
> +int gw_ares_init(gw_ares_channel_t **channel, struct gw_ares_options *opts)
> +{
> +       gw_ares_channel_t *c;
> +       int ret;
> +
> +       if (!opts->nr_server)
> +               return -EINVAL;
> +
> +       *channel = malloc(sizeof(**channel));
> +       if (!*channel)
> +               return -ENOMEM;
> +
> +       c = *channel;
> +       c->nr_server = opts->nr_server;
> +       c->servers = malloc(c->nr_server * sizeof(*c->servers));
> +       if (!c->servers) {
> +               free(*channel);
> +               return -ENOMEM;
> +       }

This can set:

   c = malloc(sizeof(*c))

first, then on on success set:

   *channel = c;

I don't see a valid reason to fill a dangling pointer if it fails.

-- Viro