static int pfkey_migrate(struct sock *sk, struct sk_buff *skb,
			 const struct sadb_msg *hdr, void * const *ext_hdrs)
{
	int i, len, ret, err = -EINVAL;
	u8 dir;
	struct sadb_address *sa;
	struct sadb_x_kmaddress *kma;
	struct sadb_x_policy *pol;
	struct sadb_x_ipsecrequest *rq;
	struct xfrm_selector sel;
	struct xfrm_migrate m[XFRM_MAX_DEPTH];
	struct xfrm_kmaddress k;

	if (!present_and_same_family(ext_hdrs[SADB_EXT_ADDRESS_SRC - 1],
				     ext_hdrs[SADB_EXT_ADDRESS_DST - 1]) ||
	    !ext_hdrs[SADB_X_EXT_POLICY - 1]) {
		err = -EINVAL;
		goto out;
	}

	kma = ext_hdrs[SADB_X_EXT_KMADDRESS - 1];
	pol = ext_hdrs[SADB_X_EXT_POLICY - 1];

	if (pol->sadb_x_policy_dir >= IPSEC_DIR_MAX) {
		err = -EINVAL;
		goto out;
	}

	if (kma) {
		/* convert sadb_x_kmaddress to xfrm_kmaddress */
		k.reserved = kma->sadb_x_kmaddress_reserved;
		ret = parse_sockaddr_pair((struct sockaddr *)(kma + 1),
					  8*(kma->sadb_x_kmaddress_len) - sizeof(*kma),
					  &k.local, &k.remote, &k.family);
		if (ret < 0) {
			err = ret;
			goto out;
		}
	}

	dir = pol->sadb_x_policy_dir - 1;
	memset(&sel, 0, sizeof(sel));

	/* set source address info of selector */
	sa = ext_hdrs[SADB_EXT_ADDRESS_SRC - 1];
	sel.family = pfkey_sadb_addr2xfrm_addr(sa, &sel.saddr);
	sel.prefixlen_s = sa->sadb_address_prefixlen;
	sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	sel.sport = ((struct sockaddr_in *)(sa + 1))->sin_port;
	if (sel.sport)
		sel.sport_mask = htons(0xffff);

	/* set destination address info of selector */
	sa = ext_hdrs[SADB_EXT_ADDRESS_DST - 1],
	pfkey_sadb_addr2xfrm_addr(sa, &sel.daddr);
	sel.prefixlen_d = sa->sadb_address_prefixlen;
	sel.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	sel.dport = ((struct sockaddr_in *)(sa + 1))->sin_port;
	if (sel.dport)
		sel.dport_mask = htons(0xffff);

	rq = (struct sadb_x_ipsecrequest *)(pol + 1);

	/* extract ipsecrequests */
	i = 0;
	len = pol->sadb_x_policy_len * 8 - sizeof(struct sadb_x_policy);

	while (len > 0 && i < XFRM_MAX_DEPTH) {
		ret = ipsecrequests_to_migrate(rq, len, &m[i]);
		if (ret < 0) {
			err = ret;
			goto out;
		} else {
			rq = (struct sadb_x_ipsecrequest *)((u8 *)rq + ret);
			len -= ret;
			i++;
		}
	}

	if (!i || len > 0) {
		err = -EINVAL;
		goto out;
	}

	return xfrm_migrate(&sel, dir, XFRM_POLICY_TYPE_MAIN, m, i,
			    kma ? &k : NULL);

 out:
	return err;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.