On Mon, 2024-04-08 at 08:24 -0700, Yonghong Song wrote:
[...]
> +/* Handle the following two cases:
> + * case 1: link != NULL, prog != NULL, old != NULL
> + * case 2: link != NULL, prog != NULL, old == NULL
> + */
> +static int sock_map_link_update_prog(struct bpf_link *link,
> + struct bpf_prog *prog,
> + struct bpf_prog *old)
> +{
> + const struct sockmap_link *sockmap_link = container_of(link, struct sockmap_link, link);
> + struct bpf_prog **pprog, *old_link_prog;
> + struct bpf_link **plink;
> + int ret = 0;
> +
> + mutex_lock(&sockmap_mutex);
> +
> + /* If old prog is not NULL, ensure old prog is the same as link->prog. */
> + if (old && link->prog != old) {
> + ret = -EPERM;
> + goto out;
> + }
> + /* Ensure link->prog has the same type/attach_type as the new prog. */
> + if (link->prog->type != prog->type ||
> + link->prog->expected_attach_type != prog->expected_attach_type) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + ret = sock_map_prog_link_lookup(sockmap_link->map, &pprog, &plink,
> + sockmap_link->attach_type);
> + if (ret)
> + goto out;
> +
> + /* return error if the stored bpf_link does not match the incoming bpf_link. */
> + if (link != *plink)
> + return -EBUSY;
Hi Yonghong,
Sorry, this was a mistake on my side,
this needs a 'goto out' in order to unlock the mutex.
Thanks,
Eduard
> +
> + if (old) {
> + ret = psock_replace_prog(pprog, prog, old);
> + if (ret)
> + goto out;
> + } else {
> + psock_set_prog(pprog, prog);
> + }
> +
> + bpf_prog_inc(prog);
> + old_link_prog = xchg(&link->prog, prog);
> + bpf_prog_put(old_link_prog);
> +
> +out:
> + mutex_unlock(&sockmap_mutex);
> + return ret;
> +}
