__netlink_kernel_create(struct net *net, int unit, struct module *module,
			struct netlink_kernel_cfg *cfg)
{
	struct socket *sock;
	struct sock *sk;
	struct netlink_sock *nlk;
	struct listeners *listeners = NULL;
	struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL;
	unsigned int groups;

	BUG_ON(!nl_table);

	if (unit < 0 || unit >= MAX_LINKS)
		return NULL;

	if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
		return NULL;

	/*
	 * We have to just have a reference on the net from sk, but don't
	 * get_net it. Besides, we cannot get and then put the net here.
	 * So we create one inside init_net and the move it to net.
	 */

	if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0)
		goto out_sock_release_nosk;

	sk = sock->sk;
	sk_change_net(sk, net);

	if (!cfg || cfg->groups < 32)
		groups = 32;
	else
		groups = cfg->groups;

	listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
	if (!listeners)
		goto out_sock_release;

	sk->sk_data_ready = netlink_data_ready;
	if (cfg && cfg->input)
		nlk_sk(sk)->netlink_rcv = cfg->input;

	if (netlink_insert(sk, net, 0))
		goto out_sock_release;

	nlk = nlk_sk(sk);
	nlk->flags |= NETLINK_KERNEL_SOCKET;

	netlink_table_grab();
	if (!nl_table[unit].registered) {
		nl_table[unit].groups = groups;
		rcu_assign_pointer(nl_table[unit].listeners, listeners);
		nl_table[unit].cb_mutex = cb_mutex;
		nl_table[unit].module = module;
		if (cfg) {
			nl_table[unit].bind = cfg->bind;
			nl_table[unit].flags = cfg->flags;
			if (cfg->compare)
				nl_table[unit].compare = cfg->compare;
		}
		nl_table[unit].registered = 1;
	} else {
		kfree(listeners);
		nl_table[unit].registered++;
	}
	netlink_table_ungrab();
	return sk;

out_sock_release:
	kfree(listeners);
	netlink_kernel_release(sk);
	return NULL;

out_sock_release_nosk:
	sock_release(sock);
	return NULL;
}

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.