static int cma_check_linklocal(struct rdma_dev_addr *dev_addr,
			       struct sockaddr *addr)
{
#if IS_ENABLED(CONFIG_IPV6)
	struct sockaddr_in6 *sin6;

	if (addr->sa_family != AF_INET6)
		return 0;

	sin6 = (struct sockaddr_in6 *) addr;

	if (!(ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL))
		return 0;

	if (!sin6->sin6_scope_id)
			return -EINVAL;

	dev_addr->bound_dev_if = sin6->sin6_scope_id;
#endif
	return 0;
}

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.