1 files changed, 112 insertions, 111 deletions

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 8b3ef404c794..15792d8b6272 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -50,37 +50,40 @@ static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family);
 static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo);
 static void xfrm_init_pmtu(struct dst_entry *dst);
 static int stale_bundle(struct dst_entry *dst);
-static int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *xdst,
-			  struct flowi *fl, int family, int strict);
+static int xfrm_bundle_ok(struct xfrm_dst *xdst, int family);
 
 
 static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
 						int dir);
 
 static inline int
-__xfrm4_selector_match(struct xfrm_selector *sel, struct flowi *fl)
+__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 {
-	return  addr_match(&fl->fl4_dst, &sel->daddr, sel->prefixlen_d) &&
-		addr_match(&fl->fl4_src, &sel->saddr, sel->prefixlen_s) &&
-		!((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
-		!((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
-		(fl->proto == sel->proto || !sel->proto) &&
-		(fl->oif == sel->ifindex || !sel->ifindex);
+	const struct flowi4 *fl4 = &fl->u.ip4;
+
+	return  addr_match(&fl4->daddr, &sel->daddr, sel->prefixlen_d) &&
+		addr_match(&fl4->saddr, &sel->saddr, sel->prefixlen_s) &&
+		!((xfrm_flowi_dport(fl, &fl4->uli) ^ sel->dport) & sel->dport_mask) &&
+		!((xfrm_flowi_sport(fl, &fl4->uli) ^ sel->sport) & sel->sport_mask) &&
+		(fl4->flowi4_proto == sel->proto || !sel->proto) &&
+		(fl4->flowi4_oif == sel->ifindex || !sel->ifindex);
 }
 
 static inline int
-__xfrm6_selector_match(struct xfrm_selector *sel, struct flowi *fl)
+__xfrm6_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
 {
-	return  addr_match(&fl->fl6_dst, &sel->daddr, sel->prefixlen_d) &&
-		addr_match(&fl->fl6_src, &sel->saddr, sel->prefixlen_s) &&
-		!((xfrm_flowi_dport(fl) ^ sel->dport) & sel->dport_mask) &&
-		!((xfrm_flowi_sport(fl) ^ sel->sport) & sel->sport_mask) &&
-		(fl->proto == sel->proto || !sel->proto) &&
-		(fl->oif == sel->ifindex || !sel->ifindex);
+	const struct flowi6 *fl6 = &fl->u.ip6;
+
+	return  addr_match(&fl6->daddr, &sel->daddr, sel->prefixlen_d) &&
+		addr_match(&fl6->saddr, &sel->saddr, sel->prefixlen_s) &&
+		!((xfrm_flowi_dport(fl, &fl6->uli) ^ sel->dport) & sel->dport_mask) &&
+		!((xfrm_flowi_sport(fl, &fl6->uli) ^ sel->sport) & sel->sport_mask) &&
+		(fl6->flowi6_proto == sel->proto || !sel->proto) &&
+		(fl6->flowi6_oif == sel->ifindex || !sel->ifindex);
 }
 
-int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
-		    unsigned short family)
+int xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl,
+			unsigned short family)
 {
 	switch (family) {
 	case AF_INET:
@@ -92,8 +95,8 @@ int xfrm_selector_match(struct xfrm_selector *sel, struct flowi *fl,
 }
 
 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net, int tos,
-						  xfrm_address_t *saddr,
-						  xfrm_address_t *daddr,
+						  const xfrm_address_t *saddr,
+						  const xfrm_address_t *daddr,
 						  int family)
 {
 	struct xfrm_policy_afinfo *afinfo;
@@ -311,7 +314,9 @@ static inline unsigned int idx_hash(struct net *net, u32 index)
 	return __idx_hash(index, net->xfrm.policy_idx_hmask);
 }
 
-static struct hlist_head *policy_hash_bysel(struct net *net, struct xfrm_selector *sel, unsigned short family, int dir)
+static struct hlist_head *policy_hash_bysel(struct net *net,
+					    const struct xfrm_selector *sel,
+					    unsigned short family, int dir)
 {
 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 	unsigned int hash = __sel_hash(sel, family, hmask);
@@ -321,7 +326,10 @@ static struct hlist_head *policy_hash_bysel(struct net *net, struct xfrm_selecto
 		net->xfrm.policy_bydst[dir].table + hash);
 }
 
-static struct hlist_head *policy_hash_direct(struct net *net, xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, int dir)
+static struct hlist_head *policy_hash_direct(struct net *net,
+					     const xfrm_address_t *daddr,
+					     const xfrm_address_t *saddr,
+					     unsigned short family, int dir)
 {
 	unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
 	unsigned int hash = __addr_hash(daddr, saddr, family, hmask);
@@ -864,32 +872,33 @@ EXPORT_SYMBOL(xfrm_policy_walk_done);
  *
  * Returns 0 if policy found, else an -errno.
  */
-static int xfrm_policy_match(struct xfrm_policy *pol, struct flowi *fl,
+static int xfrm_policy_match(const struct xfrm_policy *pol,
+			     const struct flowi *fl,
 			     u8 type, u16 family, int dir)
 {
-	struct xfrm_selector *sel = &pol->selector;
+	const struct xfrm_selector *sel = &pol->selector;
 	int match, ret = -ESRCH;
 
 	if (pol->family != family ||
-	    (fl->mark & pol->mark.m) != pol->mark.v ||
+	    (fl->flowi_mark & pol->mark.m) != pol->mark.v ||
 	    pol->type != type)
 		return ret;
 
 	match = xfrm_selector_match(sel, fl, family);
 	if (match)
-		ret = security_xfrm_policy_lookup(pol->security, fl->secid,
+		ret = security_xfrm_policy_lookup(pol->security, fl->flowi_secid,
 						  dir);
 
 	return ret;
 }
 
 static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
-						     struct flowi *fl,
+						     const struct flowi *fl,
 						     u16 family, u8 dir)
 {
 	int err;
 	struct xfrm_policy *pol, *ret;
-	xfrm_address_t *daddr, *saddr;
+	const xfrm_address_t *daddr, *saddr;
 	struct hlist_node *entry;
 	struct hlist_head *chain;
 	u32 priority = ~0U;
@@ -941,7 +950,7 @@ fail:
 }
 
 static struct xfrm_policy *
-__xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir)
+__xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir)
 {
 #ifdef CONFIG_XFRM_SUB_POLICY
 	struct xfrm_policy *pol;
@@ -954,7 +963,7 @@ __xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir)
 }
 
 static struct flow_cache_object *
-xfrm_policy_lookup(struct net *net, struct flowi *fl, u16 family,
+xfrm_policy_lookup(struct net *net, const struct flowi *fl, u16 family,
 		   u8 dir, struct flow_cache_object *old_obj, void *ctx)
 {
 	struct xfrm_policy *pol;
@@ -990,7 +999,8 @@ static inline int policy_to_flow_dir(int dir)
 	}
 }
 
-static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struct flowi *fl)
+static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir,
+						 const struct flowi *fl)
 {
 	struct xfrm_policy *pol;
 
@@ -1006,7 +1016,7 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(struct sock *sk, int dir, struc
 				goto out;
 			}
 			err = security_xfrm_policy_lookup(pol->security,
-						      fl->secid,
+						      fl->flowi_secid,
 						      policy_to_flow_dir(dir));
 			if (!err)
 				xfrm_pol_hold(pol);
@@ -1098,7 +1108,7 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
 	return 0;
 }
 
-static struct xfrm_policy *clone_policy(struct xfrm_policy *old, int dir)
+static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
 {
 	struct xfrm_policy *newp = xfrm_policy_alloc(xp_net(old), GFP_ATOMIC);
 
@@ -1157,9 +1167,8 @@ xfrm_get_saddr(struct net *net, xfrm_address_t *local, xfrm_address_t *remote,
 /* Resolve list of templates for the flow, given policy. */
 
 static int
-xfrm_tmpl_resolve_one(struct xfrm_policy *policy, struct flowi *fl,
-		      struct xfrm_state **xfrm,
-		      unsigned short family)
+xfrm_tmpl_resolve_one(struct xfrm_policy *policy, const struct flowi *fl,
+		      struct xfrm_state **xfrm, unsigned short family)
 {
 	struct net *net = xp_net(policy);
 	int nx;
@@ -1214,9 +1223,8 @@ fail:
 }
 
 static int
-xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
-		  struct xfrm_state **xfrm,
-		  unsigned short family)
+xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
+		  struct xfrm_state **xfrm, unsigned short family)
 {
 	struct xfrm_state *tp[XFRM_MAX_DEPTH];
 	struct xfrm_state **tpp = (npols > 1) ? tp : xfrm;
@@ -1256,7 +1264,7 @@ xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, struct flowi *fl,
  * still valid.
  */
 
-static inline int xfrm_get_tos(struct flowi *fl, int family)
+static inline int xfrm_get_tos(const struct flowi *fl, int family)
 {
 	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 	int tos;
@@ -1340,10 +1348,13 @@ static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
 	default:
 		BUG();
 	}
-	xdst = dst_alloc(dst_ops) ?: ERR_PTR(-ENOBUFS);
+	xdst = dst_alloc(dst_ops, 0);
 	xfrm_policy_put_afinfo(afinfo);
 
-	xdst->flo.ops = &xfrm_bundle_fc_ops;
+	if (likely(xdst))
+		xdst->flo.ops = &xfrm_bundle_fc_ops;
+	else
+		xdst = ERR_PTR(-ENOBUFS);
 
 	return xdst;
 }
@@ -1366,7 +1377,7 @@ static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
 }
 
 static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
-				struct flowi *fl)
+				const struct flowi *fl)
 {
 	struct xfrm_policy_afinfo *afinfo =
 		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
@@ -1389,7 +1400,7 @@ static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
 
 static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
 					    struct xfrm_state **xfrm, int nx,
-					    struct flowi *fl,
+					    const struct flowi *fl,
 					    struct dst_entry *dst)
 {
 	struct net *net = xp_net(policy);
@@ -1505,7 +1516,7 @@ free_dst:
 }
 
 static int inline
-xfrm_dst_alloc_copy(void **target, void *src, int size)
+xfrm_dst_alloc_copy(void **target, const void *src, int size)
 {
 	if (!*target) {
 		*target = kmalloc(size, GFP_ATOMIC);
@@ -1517,7 +1528,7 @@ xfrm_dst_alloc_copy(void **target, void *src, int size)
 }
 
 static int inline
-xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
+xfrm_dst_update_parent(struct dst_entry *dst, const struct xfrm_selector *sel)
 {
 #ifdef CONFIG_XFRM_SUB_POLICY
 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
@@ -1529,7 +1540,7 @@ xfrm_dst_update_parent(struct dst_entry *dst, struct xfrm_selector *sel)
 }
 
 static int inline
-xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
+xfrm_dst_update_origin(struct dst_entry *dst, const struct flowi *fl)
 {
 #ifdef CONFIG_XFRM_SUB_POLICY
 	struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
@@ -1539,7 +1550,7 @@ xfrm_dst_update_origin(struct dst_entry *dst, struct flowi *fl)
 #endif
 }
 
-static int xfrm_expand_policies(struct flowi *fl, u16 family,
+static int xfrm_expand_policies(const struct flowi *fl, u16 family,
 				struct xfrm_policy **pols,
 				int *num_pols, int *num_xfrms)
 {
@@ -1585,7 +1596,7 @@ static int xfrm_expand_policies(struct flowi *fl, u16 family,
 
 static struct xfrm_dst *
 xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
-			       struct flowi *fl, u16 family,
+			       const struct flowi *fl, u16 family,
 			       struct dst_entry *dst_orig)
 {
 	struct net *net = xp_net(pols[0]);
@@ -1628,7 +1639,7 @@ xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
 }
 
 static struct flow_cache_object *
-xfrm_bundle_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir,
+xfrm_bundle_lookup(struct net *net, const struct flowi *fl, u16 family, u8 dir,
 		   struct flow_cache_object *oldflo, void *ctx)
 {
 	struct dst_entry *dst_orig = (struct dst_entry *)ctx;
@@ -1727,18 +1738,36 @@ error:
 	return ERR_PTR(err);
 }
 
+static struct dst_entry *make_blackhole(struct net *net, u16 family,
+					struct dst_entry *dst_orig)
+{
+	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	struct dst_entry *ret;
+
+	if (!afinfo) {
+		dst_release(dst_orig);
+		ret = ERR_PTR(-EINVAL);
+	} else {
+		ret = afinfo->blackhole_route(net, dst_orig);
+	}
+	xfrm_policy_put_afinfo(afinfo);
+
+	return ret;
+}
+
 /* Main function: finds/creates a bundle for given flow.
  *
  * At the moment we eat a raw IP route. Mostly to speed up lookups
  * on interfaces with disabled IPsec.
  */
-int __xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
-		  struct sock *sk, int flags)
+struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
+			      const struct flowi *fl,
+			      struct sock *sk, int flags)
 {
 	struct xfrm_policy *pols[XFRM_POLICY_TYPE_MAX];
 	struct flow_cache_object *flo;
 	struct xfrm_dst *xdst;
-	struct dst_entry *dst, *dst_orig = *dst_p, *route;
+	struct dst_entry *dst, *route;
 	u16 family = dst_orig->ops->family;
 	u8 dir = policy_to_flow_dir(XFRM_POLICY_OUT);
 	int i, err, num_pols, num_xfrms = 0, drop_pols = 0;
@@ -1775,6 +1804,8 @@ restart:
 				goto no_transform;
 			}
 
+			dst_hold(&xdst->u.dst);
+
 			spin_lock_bh(&xfrm_policy_sk_bundle_lock);
 			xdst->u.dst.next = xfrm_policy_sk_bundles;
 			xfrm_policy_sk_bundles = &xdst->u.dst;
@@ -1820,9 +1851,10 @@ restart:
 			dst_release(dst);
 			xfrm_pols_put(pols, drop_pols);
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTNOSTATES);
-			return -EREMOTE;
+
+			return make_blackhole(net, family, dst_orig);
 		}
-		if (flags & XFRM_LOOKUP_WAIT) {
+		if (fl->flowi_flags & FLOWI_FLAG_CAN_SLEEP) {
 			DECLARE_WAITQUEUE(wait, current);
 
 			add_wait_queue(&net->xfrm.km_waitq, &wait);
@@ -1864,47 +1896,33 @@ no_transform:
 		goto error;
 	} else if (num_xfrms > 0) {
 		/* Flow transformed */
-		*dst_p = dst;
 		dst_release(dst_orig);
 	} else {
 		/* Flow passes untransformed */
 		dst_release(dst);
+		dst = dst_orig;
 	}
 ok:
 	xfrm_pols_put(pols, drop_pols);
-	return 0;
+	return dst;
 
 nopol:
-	if (!(flags & XFRM_LOOKUP_ICMP))
+	if (!(flags & XFRM_LOOKUP_ICMP)) {
+		dst = dst_orig;
 		goto ok;
+	}
 	err = -ENOENT;
 error:
 	dst_release(dst);
 dropdst:
 	dst_release(dst_orig);
-	*dst_p = NULL;
 	xfrm_pols_put(pols, drop_pols);
-	return err;
-}
-EXPORT_SYMBOL(__xfrm_lookup);
-
-int xfrm_lookup(struct net *net, struct dst_entry **dst_p, struct flowi *fl,
-		struct sock *sk, int flags)
-{
-	int err = __xfrm_lookup(net, dst_p, fl, sk, flags);
-
-	if (err == -EREMOTE) {
-		dst_release(*dst_p);
-		*dst_p = NULL;
-		err = -EAGAIN;
-	}
-
-	return err;
+	return ERR_PTR(err);
 }
 EXPORT_SYMBOL(xfrm_lookup);
 
 static inline int
-xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
+xfrm_secpath_reject(int idx, struct sk_buff *skb, const struct flowi *fl)
 {
 	struct xfrm_state *x;
 
@@ -1923,7 +1941,7 @@ xfrm_secpath_reject(int idx, struct sk_buff *skb, struct flowi *fl)
  */
 
 static inline int
-xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
+xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
 	      unsigned short family)
 {
 	if (xfrm_state_kern(x))
@@ -1946,7 +1964,7 @@ xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
  * Otherwise "-2 - errored_index" is returned.
  */
 static inline int
-xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
+xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
 	       unsigned short family)
 {
 	int idx = start;
@@ -1978,13 +1996,13 @@ int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
 		return -EAFNOSUPPORT;
 
 	afinfo->decode_session(skb, fl, reverse);
-	err = security_xfrm_decode_session(skb, &fl->secid);
+	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
 	xfrm_policy_put_afinfo(afinfo);
 	return err;
 }
 EXPORT_SYMBOL(__xfrm_decode_session);
 
-static inline int secpath_has_nontransport(struct sec_path *sp, int k, int *idxp)
+static inline int secpath_has_nontransport(const struct sec_path *sp, int k, int *idxp)
 {
 	for (; k < sp->len; k++) {
 		if (sp->xvec[k]->props.mode != XFRM_MODE_TRANSPORT) {
@@ -2159,7 +2177,7 @@ int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 	struct net *net = dev_net(skb->dev);
 	struct flowi fl;
 	struct dst_entry *dst;
-	int res;
+	int res = 1;
 
 	if (xfrm_decode_session(skb, &fl, family) < 0) {
 		XFRM_INC_STATS(net, LINUX_MIB_XFRMFWDHDRERROR);
@@ -2167,9 +2185,12 @@ int __xfrm_route_forward(struct sk_buff *skb, unsigned short family)
 	}
 
 	skb_dst_force(skb);
-	dst = skb_dst(skb);
 
-	res = xfrm_lookup(net, &dst, &fl, NULL, 0) == 0;
+	dst = xfrm_lookup(net, skb_dst(skb), &fl, NULL, 0);
+	if (IS_ERR(dst)) {
+		res = 0;
+		dst = NULL;
+	}
 	skb_dst_set(skb, dst);
 	return res;
 }
@@ -2207,7 +2228,7 @@ static struct dst_entry *xfrm_dst_check(struct dst_entry *dst, u32 cookie)
 
 static int stale_bundle(struct dst_entry *dst)
 {
-	return !xfrm_bundle_ok(NULL, (struct xfrm_dst *)dst, NULL, AF_UNSPEC, 0);
+	return !xfrm_bundle_ok((struct xfrm_dst *)dst, AF_UNSPEC);
 }
 
 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev)
@@ -2279,8 +2300,7 @@ static void xfrm_init_pmtu(struct dst_entry *dst)
  * still valid.
  */
 
-static int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
-		struct flowi *fl, int family, int strict)
+static int xfrm_bundle_ok(struct xfrm_dst *first, int family)
 {
 	struct dst_entry *dst = &first->u.dst;
 	struct xfrm_dst *last;
@@ -2289,26 +2309,12 @@ static int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
 	if (!dst_check(dst->path, ((struct xfrm_dst *)dst)->path_cookie) ||
 	    (dst->dev && !netif_running(dst->dev)))
 		return 0;
-#ifdef CONFIG_XFRM_SUB_POLICY
-	if (fl) {
-		if (first->origin && !flow_cache_uli_match(first->origin, fl))
-			return 0;
-		if (first->partner &&
-		    !xfrm_selector_match(first->partner, fl, family))
-			return 0;
-	}
-#endif
 
 	last = NULL;
 
 	do {
 		struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
 
-		if (fl && !xfrm_selector_match(&dst->xfrm->sel, fl, family))
-			return 0;
-		if (fl && pol &&
-		    !security_xfrm_state_pol_flow_match(dst->xfrm, pol, fl))
-			return 0;
 		if (dst->xfrm->km.state != XFRM_STATE_VALID)
 			return 0;
 		if (xdst->xfrm_genid != dst->xfrm->genid)
@@ -2317,11 +2323,6 @@ static int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
 		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
 			return 0;
 
-		if (strict && fl &&
-		    !(dst->xfrm->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) &&
-		    !xfrm_state_addr_flow_check(dst->xfrm, fl, family))
-			return 0;
-
 		mtu = dst_mtu(dst->child);
 		if (xdst->child_mtu_cached != mtu) {
 			last = xdst;
@@ -2732,8 +2733,8 @@ EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
 #endif
 
 #ifdef CONFIG_XFRM_MIGRATE
-static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
-				       struct xfrm_selector *sel_tgt)
+static int xfrm_migrate_selector_match(const struct xfrm_selector *sel_cmp,
+				       const struct xfrm_selector *sel_tgt)
 {
 	if (sel_cmp->proto == IPSEC_ULPROTO_ANY) {
 		if (sel_tgt->family == sel_cmp->family &&
@@ -2753,7 +2754,7 @@ static int xfrm_migrate_selector_match(struct xfrm_selector *sel_cmp,
 	return 0;
 }
 
-static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
+static struct xfrm_policy * xfrm_migrate_policy_find(const struct xfrm_selector *sel,
 						     u8 dir, u8 type)
 {
 	struct xfrm_policy *pol, *ret = NULL;
@@ -2789,7 +2790,7 @@ static struct xfrm_policy * xfrm_migrate_policy_find(struct xfrm_selector *sel,
 	return ret;
 }
 
-static int migrate_tmpl_match(struct xfrm_migrate *m, struct xfrm_tmpl *t)
+static int migrate_tmpl_match(const struct xfrm_migrate *m, const struct xfrm_tmpl *t)
 {
 	int match = 0;
 
@@ -2859,7 +2860,7 @@ static int xfrm_policy_migrate(struct xfrm_policy *pol,
 	return 0;
 }
 
-static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
+static int xfrm_migrate_check(const struct xfrm_migrate *m, int num_migrate)
 {
 	int i, j;
 
@@ -2893,7 +2894,7 @@ static int xfrm_migrate_check(struct xfrm_migrate *m, int num_migrate)
 	return 0;
 }
 
-int xfrm_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
+int xfrm_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
 		 struct xfrm_migrate *m, int num_migrate,
 		 struct xfrm_kmaddress *k)
 {