int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code)
{
	struct netlink_set_err_data info;
	struct sock *sk;
	int ret = 0;

	info.exclude_sk = ssk;
	info.portid = portid;
	info.group = group;
	/* sk->sk_err wants a positive error value */
	info.code = -code;

	read_lock(&nl_table_lock);

	sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list)
		ret += do_one_set_err(sk, &info);

	read_unlock(&nl_table_lock);
	return ret;
}

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.