static int pfkey_spdadd(struct sock *sk, struct sk_buff *skb, const struct sadb_msg *hdr, void * const *ext_hdrs)
{
	struct net *net = sock_net(sk);
	int err = 0;
	struct sadb_lifetime *lifetime;
	struct sadb_address *sa;
	struct sadb_x_policy *pol;
	struct xfrm_policy *xp;
	struct km_event c;
	struct sadb_x_sec_ctx *sec_ctx;

	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])
		return -EINVAL;

	pol = ext_hdrs[SADB_X_EXT_POLICY-1];
	if (pol->sadb_x_policy_type > IPSEC_POLICY_IPSEC)
		return -EINVAL;
	if (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir >= IPSEC_DIR_MAX)
		return -EINVAL;

	xp = xfrm_policy_alloc(net, GFP_KERNEL);
	if (xp == NULL)
		return -ENOBUFS;

	xp->action = (pol->sadb_x_policy_type == IPSEC_POLICY_DISCARD ?
		      XFRM_POLICY_BLOCK : XFRM_POLICY_ALLOW);
	xp->priority = pol->sadb_x_policy_priority;

	sa = ext_hdrs[SADB_EXT_ADDRESS_SRC-1];
	xp->family = pfkey_sadb_addr2xfrm_addr(sa, &xp->selector.saddr);
	if (!xp->family) {
		err = -EINVAL;
		goto out;
	}
	xp->selector.family = xp->family;
	xp->selector.prefixlen_s = sa->sadb_address_prefixlen;
	xp->selector.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);
	xp->selector.sport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (xp->selector.sport)
		xp->selector.sport_mask = htons(0xffff);

	sa = ext_hdrs[SADB_EXT_ADDRESS_DST-1];
	pfkey_sadb_addr2xfrm_addr(sa, &xp->selector.daddr);
	xp->selector.prefixlen_d = sa->sadb_address_prefixlen;

	/* Amusing, we set this twice.  KAME apps appear to set same value
	 * in both addresses.
	 */
	xp->selector.proto = pfkey_proto_to_xfrm(sa->sadb_address_proto);

	xp->selector.dport = ((struct sockaddr_in *)(sa+1))->sin_port;
	if (xp->selector.dport)
		xp->selector.dport_mask = htons(0xffff);

	sec_ctx = ext_hdrs[SADB_X_EXT_SEC_CTX - 1];
	if (sec_ctx != NULL) {
		struct xfrm_user_sec_ctx *uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx);

		if (!uctx) {
			err = -ENOBUFS;
			goto out;
		}

		err = security_xfrm_policy_alloc(&xp->security, uctx);
		kfree(uctx);

		if (err)
			goto out;
	}

	xp->lft.soft_byte_limit = XFRM_INF;
	xp->lft.hard_byte_limit = XFRM_INF;
	xp->lft.soft_packet_limit = XFRM_INF;
	xp->lft.hard_packet_limit = XFRM_INF;
	if ((lifetime = ext_hdrs[SADB_EXT_LIFETIME_HARD-1]) != NULL) {
		xp->lft.hard_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
		xp->lft.hard_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
		xp->lft.hard_add_expires_seconds = lifetime->sadb_lifetime_addtime;
		xp->lft.hard_use_expires_seconds = lifetime->sadb_lifetime_usetime;
	}
	if ((lifetime = ext_hdrs[SADB_EXT_LIFETIME_SOFT-1]) != NULL) {
		xp->lft.soft_packet_limit = _KEY2X(lifetime->sadb_lifetime_allocations);
		xp->lft.soft_byte_limit = _KEY2X(lifetime->sadb_lifetime_bytes);
		xp->lft.soft_add_expires_seconds = lifetime->sadb_lifetime_addtime;
		xp->lft.soft_use_expires_seconds = lifetime->sadb_lifetime_usetime;
	}
	xp->xfrm_nr = 0;
	if (pol->sadb_x_policy_type == IPSEC_POLICY_IPSEC &&
	    (err = parse_ipsecrequests(xp, pol)) < 0)
		goto out;

	err = xfrm_policy_insert(pol->sadb_x_policy_dir-1, xp,
				 hdr->sadb_msg_type != SADB_X_SPDUPDATE);

	xfrm_audit_policy_add(xp, err ? 0 : 1,
			      audit_get_loginuid(current),
			      audit_get_sessionid(current), 0);

	if (err)
		goto out;

	if (hdr->sadb_msg_type == SADB_X_SPDUPDATE)
		c.event = XFRM_MSG_UPDPOLICY;
	else
		c.event = XFRM_MSG_NEWPOLICY;

	c.seq = hdr->sadb_msg_seq;
	c.portid = hdr->sadb_msg_pid;

	km_policy_notify(xp, pol->sadb_x_policy_dir-1, &c);
	xfrm_pol_put(xp);
	return 0;

out:
	xp->walk.dead = 1;
	xfrm_policy_destroy(xp);
	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.