static struct xfrm_policy *pfkey_compile_policy(struct sock *sk, int opt,
						u8 *data, int len, int *dir)
{
	struct net *net = sock_net(sk);
	struct xfrm_policy *xp;
	struct sadb_x_policy *pol = (struct sadb_x_policy*)data;
	struct sadb_x_sec_ctx *sec_ctx;

	switch (sk->sk_family) {
	case AF_INET:
		if (opt != IP_IPSEC_POLICY) {
			*dir = -EOPNOTSUPP;
			return NULL;
		}
		break;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		if (opt != IPV6_IPSEC_POLICY) {
			*dir = -EOPNOTSUPP;
			return NULL;
		}
		break;
#endif
	default:
		*dir = -EINVAL;
		return NULL;
	}

	*dir = -EINVAL;

	if (len < sizeof(struct sadb_x_policy) ||
	    pol->sadb_x_policy_len*8 > len ||
	    pol->sadb_x_policy_type > IPSEC_POLICY_BYPASS ||
	    (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir > IPSEC_DIR_OUTBOUND))
		return NULL;

	xp = xfrm_policy_alloc(net, GFP_ATOMIC);
	if (xp == NULL) {
		*dir = -ENOBUFS;
		return NULL;
	}

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

	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;
	xp->family = sk->sk_family;

	xp->xfrm_nr = 0;
	if (pol->sadb_x_policy_type == IPSEC_POLICY_IPSEC &&
	    (*dir = parse_ipsecrequests(xp, pol)) < 0)
		goto out;

	/* security context too */
	if (len >= (pol->sadb_x_policy_len*8 +
	    sizeof(struct sadb_x_sec_ctx))) {
		char *p = (char *)pol;
		struct xfrm_user_sec_ctx *uctx;

		p += pol->sadb_x_policy_len*8;
		sec_ctx = (struct sadb_x_sec_ctx *)p;
		if (len < pol->sadb_x_policy_len*8 +
		    sec_ctx->sadb_x_sec_len*8) {
			*dir = -EINVAL;
			goto out;
		}
		if ((*dir = verify_sec_ctx_len(p)))
			goto out;
		uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx, GFP_ATOMIC);
		*dir = security_xfrm_policy_alloc(&xp->security, uctx, GFP_ATOMIC);
		kfree(uctx);

		if (*dir)
			goto out;
	}

	*dir = pol->sadb_x_policy_dir-1;
	return xp;

out:
	xp->walk.dead = 1;
	xfrm_policy_destroy(xp);
	return NULL;
}
static struct xfrm_policy *pfkey_compile_policy(struct sock *sk, int opt,
						u8 *data, int len, int *dir)
{
	struct net *net = sock_net(sk);
	struct xfrm_policy *xp;
	struct sadb_x_policy *pol = (struct sadb_x_policy*)data;
	struct sadb_x_sec_ctx *sec_ctx;

	switch (sk->sk_family) {
	case AF_INET:
		if (opt != IP_IPSEC_POLICY) {
			*dir = -EOPNOTSUPP;
			return NULL;
		}
		break;
#if IS_ENABLED(CONFIG_IPV6)
	case AF_INET6:
		if (opt != IPV6_IPSEC_POLICY) {
			*dir = -EOPNOTSUPP;
			return NULL;
		}
		break;
#endif
	default:
		*dir = -EINVAL;
		return NULL;
	}

	*dir = -EINVAL;

	if (len < sizeof(struct sadb_x_policy) ||
	    pol->sadb_x_policy_len*8 > len ||
	    pol->sadb_x_policy_type > IPSEC_POLICY_BYPASS ||
	    (!pol->sadb_x_policy_dir || pol->sadb_x_policy_dir > IPSEC_DIR_OUTBOUND))
		return NULL;

	xp = xfrm_policy_alloc(net, GFP_ATOMIC);
	if (xp == NULL) {
		*dir = -ENOBUFS;
		return NULL;
	}

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

	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;
	xp->family = sk->sk_family;

	xp->xfrm_nr = 0;
	if (pol->sadb_x_policy_type == IPSEC_POLICY_IPSEC &&
	    (*dir = parse_ipsecrequests(xp, pol)) < 0)
		goto out;

	 
	if (len >= (pol->sadb_x_policy_len*8 +
	    sizeof(struct sadb_x_sec_ctx))) {
		char *p = (char *)pol;
		struct xfrm_user_sec_ctx *uctx;

		p += pol->sadb_x_policy_len*8;
		sec_ctx = (struct sadb_x_sec_ctx *)p;
		if (len < pol->sadb_x_policy_len*8 +
		    sec_ctx->sadb_x_sec_len*8) {
			*dir = -EINVAL;
			goto out;
		}
		if ((*dir = verify_sec_ctx_len(p)))
			goto out;
		uctx = pfkey_sadb2xfrm_user_sec_ctx(sec_ctx, GFP_ATOMIC);
		*dir = security_xfrm_policy_alloc(&xp->security, uctx, GFP_ATOMIC);
		kfree(uctx);

		if (*dir)
			goto out;
	}

	*dir = pol->sadb_x_policy_dir-1;
	return xp;

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