static void sctp_destroy_sock(struct sock *sk)
{
	struct sctp_sock *sp;

	pr_debug("%s: sk:%p\n", __func__, sk);

	/* Release our hold on the endpoint. */
	sp = sctp_sk(sk);
	/* This could happen during socket init, thus we bail out
	 * early, since the rest of the below is not setup either.
	 */
	if (sp->ep == NULL)
		return;

	if (sp->do_auto_asconf) {
		sp->do_auto_asconf = 0;
		list_del(&sp->auto_asconf_list);
	}
	sctp_endpoint_free(sp->ep);
	local_bh_disable();
	percpu_counter_dec(&sctp_sockets_allocated);
	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
	local_bh_enable();
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.