static int sctp_send_asconf_add_ip(struct sock		*sk,
				   struct sockaddr	*addrs,
				   int 			addrcnt)
{
	struct net *net = sock_net(sk);
	struct sctp_sock		*sp;
	struct sctp_endpoint		*ep;
	struct sctp_association		*asoc;
	struct sctp_bind_addr		*bp;
	struct sctp_chunk		*chunk;
	struct sctp_sockaddr_entry	*laddr;
	union sctp_addr			*addr;
	union sctp_addr			saveaddr;
	void				*addr_buf;
	struct sctp_af			*af;
	struct list_head		*p;
	int 				i;
	int 				retval = 0;

	if (!net->sctp.addip_enable)
		return retval;

	sp = sctp_sk(sk);
	ep = sp->ep;

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

	list_for_each_entry(asoc, &ep->asocs, asocs) {
		if (!asoc->peer.asconf_capable)
			continue;

		if (asoc->peer.addip_disabled_mask & SCTP_PARAM_ADD_IP)
			continue;

		if (!sctp_state(asoc, ESTABLISHED))
			continue;

		/* Check if any address in the packed array of addresses is
		 * in the bind address list of the association. If so,
		 * do not send the asconf chunk to its peer, but continue with
		 * other associations.
		 */
		addr_buf = addrs;
		for (i = 0; i < addrcnt; i++) {
			addr = addr_buf;
			af = sctp_get_af_specific(addr->v4.sin_family);
			if (!af) {
				retval = -EINVAL;
				goto out;
			}

			if (sctp_assoc_lookup_laddr(asoc, addr))
				break;

			addr_buf += af->sockaddr_len;
		}
		if (i < addrcnt)
			continue;

		/* Use the first valid address in bind addr list of
		 * association as Address Parameter of ASCONF CHUNK.
		 */
		bp = &asoc->base.bind_addr;
		p = bp->address_list.next;
		laddr = list_entry(p, struct sctp_sockaddr_entry, list);
		chunk = sctp_make_asconf_update_ip(asoc, &laddr->a, addrs,
						   addrcnt, SCTP_PARAM_ADD_IP);
		if (!chunk) {
			retval = -ENOMEM;
			goto out;
		}

		/* Add the new addresses to the bind address list with
		 * use_as_src set to 0.
		 */
		addr_buf = addrs;
		for (i = 0; i < addrcnt; i++) {
			addr = addr_buf;
			af = sctp_get_af_specific(addr->v4.sin_family);
			memcpy(&saveaddr, addr, af->sockaddr_len);
			retval = sctp_add_bind_addr(bp, &saveaddr,
						    sizeof(saveaddr),
						    SCTP_ADDR_NEW, GFP_ATOMIC);
			addr_buf += af->sockaddr_len;
		}
		if (asoc->src_out_of_asoc_ok) {
			struct sctp_transport *trans;

			list_for_each_entry(trans,
			    &asoc->peer.transport_addr_list, transports) {
				/* Clear the source and route cache */
				sctp_transport_dst_release(trans);
				trans->cwnd = min(4*asoc->pathmtu, max_t(__u32,
				    2*asoc->pathmtu, 4380));
				trans->ssthresh = asoc->peer.i.a_rwnd;
				trans->rto = asoc->rto_initial;
				sctp_max_rto(asoc, trans);
				trans->rtt = trans->srtt = trans->rttvar = 0;
				sctp_transport_route(trans, NULL,
				    sctp_sk(asoc->base.sk));
			}
		}
		retval = sctp_send_asconf(asoc, chunk);
	}

out:
	return retval;
}

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.