From 960fdfdeb9e85a67bed136bc945c541ba61c2bdd Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 14:52:30 +0100
Subject: [PATCH 01/13] xfrm: input: constify xfrm_input_afinfo

Nothing writes to these structures (the module owner was not used).

While at it, size xfrm_input_afinfo[] by the highest existing xfrm family
(INET6), not AF_MAX.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h        |  5 ++---
 net/ipv4/xfrm4_protocol.c |  3 +--
 net/ipv6/xfrm6_protocol.c |  3 +--
 net/xfrm/xfrm_input.c     | 31 +++++++++++--------------------
 4 files changed, 15 insertions(+), 27 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index d9a81dcef53e..da0e4dd653e2 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -349,13 +349,12 @@ struct xfrm_state_afinfo *xfrm_state_afinfo_get_rcu(unsigned int family);
 
 struct xfrm_input_afinfo {
 	unsigned int		family;
-	struct module		*owner;
 	int			(*callback)(struct sk_buff *skb, u8 protocol,
 					    int err);
 };
 
-int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo);
-int xfrm_input_unregister_afinfo(struct xfrm_input_afinfo *afinfo);
+int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo);
+int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo);
 
 void xfrm_state_delete_tunnel(struct xfrm_state *x);
 
diff --git a/net/ipv4/xfrm4_protocol.c b/net/ipv4/xfrm4_protocol.c
index dccefa9d84cf..8dd0e6ab8606 100644
--- a/net/ipv4/xfrm4_protocol.c
+++ b/net/ipv4/xfrm4_protocol.c
@@ -188,9 +188,8 @@ static const struct net_protocol ipcomp4_protocol = {
 	.netns_ok	=	1,
 };
 
-static struct xfrm_input_afinfo xfrm4_input_afinfo = {
+static const struct xfrm_input_afinfo xfrm4_input_afinfo = {
 	.family		=	AF_INET,
-	.owner		=	THIS_MODULE,
 	.callback	=	xfrm4_rcv_cb,
 };
 
diff --git a/net/ipv6/xfrm6_protocol.c b/net/ipv6/xfrm6_protocol.c
index 54d13f8dbbae..b2dc8ce49378 100644
--- a/net/ipv6/xfrm6_protocol.c
+++ b/net/ipv6/xfrm6_protocol.c
@@ -162,9 +162,8 @@ static const struct inet6_protocol ipcomp6_protocol = {
 	.flags		=	INET6_PROTO_NOPOLICY,
 };
 
-static struct xfrm_input_afinfo xfrm6_input_afinfo = {
+static const struct xfrm_input_afinfo xfrm6_input_afinfo = {
 	.family		=	AF_INET6,
-	.owner		=	THIS_MODULE,
 	.callback	=	xfrm6_rcv_cb,
 };
 
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 3213fe8027be..8722294c6e59 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -19,19 +19,18 @@
 static struct kmem_cache *secpath_cachep __read_mostly;
 
 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
-static struct xfrm_input_afinfo __rcu *xfrm_input_afinfo[NPROTO];
+static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[AF_INET6 + 1];
 
 static struct gro_cells gro_cells;
 static struct net_device xfrm_napi_dev;
 
-int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo)
+int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
 {
 	int err = 0;
 
-	if (unlikely(afinfo == NULL))
-		return -EINVAL;
-	if (unlikely(afinfo->family >= NPROTO))
+	if (WARN_ON(afinfo->family >= ARRAY_SIZE(xfrm_input_afinfo)))
 		return -EAFNOSUPPORT;
+
 	spin_lock_bh(&xfrm_input_afinfo_lock);
 	if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL))
 		err = -EEXIST;
@@ -42,14 +41,10 @@ int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_input_register_afinfo);
 
-int xfrm_input_unregister_afinfo(struct xfrm_input_afinfo *afinfo)
+int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
 {
 	int err = 0;
 
-	if (unlikely(afinfo == NULL))
-		return -EINVAL;
-	if (unlikely(afinfo->family >= NPROTO))
-		return -EAFNOSUPPORT;
 	spin_lock_bh(&xfrm_input_afinfo_lock);
 	if (likely(xfrm_input_afinfo[afinfo->family] != NULL)) {
 		if (unlikely(xfrm_input_afinfo[afinfo->family] != afinfo))
@@ -63,12 +58,13 @@ int xfrm_input_unregister_afinfo(struct xfrm_input_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
 
-static struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
+static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
 {
-	struct xfrm_input_afinfo *afinfo;
+	const struct xfrm_input_afinfo *afinfo;
 
-	if (unlikely(family >= NPROTO))
+	if (WARN_ON_ONCE(family >= ARRAY_SIZE(xfrm_input_afinfo)))
 		return NULL;
+
 	rcu_read_lock();
 	afinfo = rcu_dereference(xfrm_input_afinfo[family]);
 	if (unlikely(!afinfo))
@@ -76,22 +72,17 @@ static struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
 	return afinfo;
 }
 
-static void xfrm_input_put_afinfo(struct xfrm_input_afinfo *afinfo)
-{
-	rcu_read_unlock();
-}
-
 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
 		       int err)
 {
 	int ret;
-	struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family);
+	const struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family);
 
 	if (!afinfo)
 		return -EAFNOSUPPORT;
 
 	ret = afinfo->callback(skb, protocol, err);
-	xfrm_input_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return ret;
 }

From f5e2bb4f5b2252e8f170f59bece2cf9a2efc8e6a Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:14 +0100
Subject: [PATCH 02/13] xfrm: policy: xfrm_get_tos cannot fail

The comment makes it look like get_tos() is used to validate something,
but it turns out the comment was about xfrm_find_bundle() which got removed
years ago.

xfrm_get_tos will return either the tos (ipv4) or 0 (ipv6).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_policy.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 99ad1af2927f..6fffa2fac607 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1538,19 +1538,13 @@ xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
 
 }
 
-/* Check that the bundle accepts the flow and its components are
- * still valid.
- */
-
-static inline int xfrm_get_tos(const struct flowi *fl, int family)
+static int xfrm_get_tos(const struct flowi *fl, int family)
 {
-	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
-	int tos;
+	struct xfrm_policy_afinfo *afinfo;
+	int tos = 0;
 
-	if (!afinfo)
-		return -EINVAL;
-
-	tos = afinfo->get_tos(fl);
+	afinfo = xfrm_policy_get_afinfo(family);
+	tos = afinfo ? afinfo->get_tos(fl) : 0;
 
 	xfrm_policy_put_afinfo(afinfo);
 
@@ -1705,9 +1699,6 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
 	xfrm_flowi_addr_get(fl, &saddr, &daddr, family);
 
 	tos = xfrm_get_tos(fl, family);
-	err = tos;
-	if (tos < 0)
-		goto put_states;
 
 	dst_hold(dst);
 

From 2b61997aa0c68ae033d066ac2d9905ada81b761a Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:15 +0100
Subject: [PATCH 03/13] xfrm: policy: xfrm_policy_unregister_afinfo can return
 void

Nothing checks the return value. Also, the errors returned on unregister
are impossible (we only support INET and INET6, so no way
xfrm_policy_afinfo[afinfo->family] can be anything other than 'afinfo'
itself).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h     |  2 +-
 net/xfrm/xfrm_policy.c | 35 +++++++++++++----------------------
 2 files changed, 14 insertions(+), 23 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index da0e4dd653e2..39037b1cce7a 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -304,7 +304,7 @@ struct xfrm_policy_afinfo {
 };
 
 int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
-int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
+void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
 void km_policy_notify(struct xfrm_policy *xp, int dir,
 		      const struct km_event *c);
 void km_state_notify(struct xfrm_state *x, const struct km_event *c);
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 6fffa2fac607..794148f76ae2 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2883,34 +2883,25 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
 
-int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
+void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 {
-	int err = 0;
-	if (unlikely(afinfo == NULL))
-		return -EINVAL;
+	struct dst_ops *dst_ops = afinfo->dst_ops;
+
 	if (unlikely(afinfo->family >= NPROTO))
-		return -EAFNOSUPPORT;
-	spin_lock(&xfrm_policy_afinfo_lock);
-	if (likely(xfrm_policy_afinfo[afinfo->family] != NULL)) {
-		if (unlikely(xfrm_policy_afinfo[afinfo->family] != afinfo))
-			err = -EINVAL;
-		else
-			RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
+		return;
+
+	if (likely(xfrm_policy_afinfo[afinfo->family] != afinfo)) {
+		RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
 					 NULL);
 	}
-	spin_unlock(&xfrm_policy_afinfo_lock);
-	if (!err) {
-		struct dst_ops *dst_ops = afinfo->dst_ops;
 
-		synchronize_rcu();
+	synchronize_rcu();
 
-		dst_ops->kmem_cachep = NULL;
-		dst_ops->check = NULL;
-		dst_ops->negative_advice = NULL;
-		dst_ops->link_failure = NULL;
-		afinfo->garbage_collect = NULL;
-	}
-	return err;
+	dst_ops->kmem_cachep = NULL;
+	dst_ops->check = NULL;
+	dst_ops->negative_advice = NULL;
+	dst_ops->link_failure = NULL;
+	afinfo->garbage_collect = NULL;
 }
 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
 

From 3d7d25a68ea5153d9d0d01c8c83acf644eab9704 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:16 +0100
Subject: [PATCH 04/13] xfrm: policy: remove garbage_collect callback

Just call xfrm_garbage_collect_deferred() directly.
This gets rid of a write to afinfo in register/unregister and allows to
constify afinfo later on.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h      | 2 +-
 net/ipv4/xfrm4_policy.c | 2 +-
 net/ipv6/xfrm6_policy.c | 2 +-
 net/xfrm/xfrm_policy.c  | 6 ++----
 4 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 39037b1cce7a..a22368edd105 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -282,7 +282,6 @@ struct xfrm_dst;
 struct xfrm_policy_afinfo {
 	unsigned short		family;
 	struct dst_ops		*dst_ops;
-	void			(*garbage_collect)(struct net *net);
 	struct dst_entry	*(*dst_lookup)(struct net *net,
 					       int tos, int oif,
 					       const xfrm_address_t *saddr,
@@ -1169,6 +1168,7 @@ static inline void xfrm_sk_free_policy(struct sock *sk)
 }
 
 void xfrm_garbage_collect(struct net *net);
+void xfrm_garbage_collect_deferred(struct net *net);
 
 #else
 
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 6a7ff6957535..77ca91d7b79c 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -219,7 +219,7 @@ static inline int xfrm4_garbage_collect(struct dst_ops *ops)
 {
 	struct net *net = container_of(ops, struct net, xfrm.xfrm4_dst_ops);
 
-	xfrm4_policy_afinfo.garbage_collect(net);
+	xfrm_garbage_collect_deferred(net);
 	return (dst_entries_get_slow(ops) > ops->gc_thresh * 2);
 }
 
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index e0f71c01d728..c273f22b12af 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -220,7 +220,7 @@ static inline int xfrm6_garbage_collect(struct dst_ops *ops)
 {
 	struct net *net = container_of(ops, struct net, xfrm.xfrm6_dst_ops);
 
-	xfrm6_policy_afinfo.garbage_collect(net);
+	xfrm_garbage_collect_deferred(net);
 	return dst_entries_get_fast(ops) > ops->gc_thresh * 2;
 }
 
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 794148f76ae2..80695a157b6e 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2733,10 +2733,11 @@ void xfrm_garbage_collect(struct net *net)
 }
 EXPORT_SYMBOL(xfrm_garbage_collect);
 
-static void xfrm_garbage_collect_deferred(struct net *net)
+void xfrm_garbage_collect_deferred(struct net *net)
 {
 	flow_cache_flush_deferred(net);
 }
+EXPORT_SYMBOL(xfrm_garbage_collect_deferred);
 
 static void xfrm_init_pmtu(struct dst_entry *dst)
 {
@@ -2873,8 +2874,6 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 			dst_ops->link_failure = xfrm_link_failure;
 		if (likely(dst_ops->neigh_lookup == NULL))
 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
-		if (likely(afinfo->garbage_collect == NULL))
-			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
 		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
 	}
 	spin_unlock(&xfrm_policy_afinfo_lock);
@@ -2901,7 +2900,6 @@ void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 	dst_ops->check = NULL;
 	dst_ops->negative_advice = NULL;
 	dst_ops->link_failure = NULL;
-	afinfo->garbage_collect = NULL;
 }
 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);
 

From a2817d8b279bc8fe62da76e6019eb9ff9d4e319c Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:17 +0100
Subject: [PATCH 05/13] xfrm: policy: remove family field

Only needed it to register the policy backend at init time.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h      |  5 ++---
 net/ipv4/xfrm4_policy.c |  5 +----
 net/ipv6/xfrm6_policy.c |  5 +----
 net/xfrm/xfrm_policy.c  | 34 +++++++++++++++++-----------------
 4 files changed, 21 insertions(+), 28 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index a22368edd105..6e061309adca 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -280,7 +280,6 @@ struct net_device;
 struct xfrm_type;
 struct xfrm_dst;
 struct xfrm_policy_afinfo {
-	unsigned short		family;
 	struct dst_ops		*dst_ops;
 	struct dst_entry	*(*dst_lookup)(struct net *net,
 					       int tos, int oif,
@@ -302,8 +301,8 @@ struct xfrm_policy_afinfo {
 	struct dst_entry	*(*blackhole_route)(struct net *net, struct dst_entry *orig);
 };
 
-int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo);
-void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo);
+int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family);
+void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo);
 void km_policy_notify(struct xfrm_policy *xp, int dir,
 		      const struct km_event *c);
 void km_state_notify(struct xfrm_state *x, const struct km_event *c);
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 77ca91d7b79c..25613539766f 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -17,8 +17,6 @@
 #include <net/ip.h>
 #include <net/l3mdev.h>
 
-static struct xfrm_policy_afinfo xfrm4_policy_afinfo;
-
 static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4,
 					    int tos, int oif,
 					    const xfrm_address_t *saddr,
@@ -272,7 +270,6 @@ static struct dst_ops xfrm4_dst_ops_template = {
 };
 
 static struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
-	.family = 		AF_INET,
 	.dst_ops =		&xfrm4_dst_ops_template,
 	.dst_lookup =		xfrm4_dst_lookup,
 	.get_saddr =		xfrm4_get_saddr,
@@ -376,7 +373,7 @@ static struct pernet_operations __net_initdata xfrm4_net_ops = {
 
 static void __init xfrm4_policy_init(void)
 {
-	xfrm_policy_register_afinfo(&xfrm4_policy_afinfo);
+	xfrm_policy_register_afinfo(&xfrm4_policy_afinfo, AF_INET);
 }
 
 void __init xfrm4_init(void)
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index c273f22b12af..3217e85334e3 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -25,8 +25,6 @@
 #include <net/mip6.h>
 #endif
 
-static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
-
 static struct dst_entry *xfrm6_dst_lookup(struct net *net, int tos, int oif,
 					  const xfrm_address_t *saddr,
 					  const xfrm_address_t *daddr)
@@ -292,7 +290,6 @@ static struct dst_ops xfrm6_dst_ops_template = {
 };
 
 static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
-	.family =		AF_INET6,
 	.dst_ops =		&xfrm6_dst_ops_template,
 	.dst_lookup =		xfrm6_dst_lookup,
 	.get_saddr =		xfrm6_get_saddr,
@@ -305,7 +302,7 @@ static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
 
 static int __init xfrm6_policy_init(void)
 {
-	return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
+	return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo, AF_INET6);
 }
 
 static void xfrm6_policy_fini(void)
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 80695a157b6e..7698785876d7 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -45,7 +45,7 @@ struct xfrm_flo {
 };
 
 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
-static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
+static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 						__read_mostly;
 
 static struct kmem_cache *xfrm_dst_cache __read_mostly;
@@ -103,11 +103,11 @@ bool xfrm_selector_match(const struct xfrm_selector *sel, const struct flowi *fl
 	return false;
 }
 
-static struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
+static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short family)
 {
-	struct xfrm_policy_afinfo *afinfo;
+	const struct xfrm_policy_afinfo *afinfo;
 
-	if (unlikely(family >= NPROTO))
+	if (unlikely(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 		return NULL;
 	rcu_read_lock();
 	afinfo = rcu_dereference(xfrm_policy_afinfo[family]);
@@ -2848,15 +2848,15 @@ static struct neighbour *xfrm_neigh_lookup(const struct dst_entry *dst,
 	return dst->path->ops->neigh_lookup(dst, skb, daddr);
 }
 
-int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
+int xfrm_policy_register_afinfo(const struct xfrm_policy_afinfo *afinfo, int family)
 {
 	int err = 0;
-	if (unlikely(afinfo == NULL))
-		return -EINVAL;
-	if (unlikely(afinfo->family >= NPROTO))
+
+	if (WARN_ON(family >= ARRAY_SIZE(xfrm_policy_afinfo)))
 		return -EAFNOSUPPORT;
+
 	spin_lock(&xfrm_policy_afinfo_lock);
-	if (unlikely(xfrm_policy_afinfo[afinfo->family] != NULL))
+	if (unlikely(xfrm_policy_afinfo[family] != NULL))
 		err = -EEXIST;
 	else {
 		struct dst_ops *dst_ops = afinfo->dst_ops;
@@ -2874,7 +2874,7 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 			dst_ops->link_failure = xfrm_link_failure;
 		if (likely(dst_ops->neigh_lookup == NULL))
 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
-		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
+		rcu_assign_pointer(xfrm_policy_afinfo[family], afinfo);
 	}
 	spin_unlock(&xfrm_policy_afinfo_lock);
 
@@ -2882,16 +2882,16 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_policy_register_afinfo);
 
-void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
+void xfrm_policy_unregister_afinfo(const struct xfrm_policy_afinfo *afinfo)
 {
 	struct dst_ops *dst_ops = afinfo->dst_ops;
+	int i;
 
-	if (unlikely(afinfo->family >= NPROTO))
-		return;
-
-	if (likely(xfrm_policy_afinfo[afinfo->family] != afinfo)) {
-		RCU_INIT_POINTER(xfrm_policy_afinfo[afinfo->family],
-					 NULL);
+	for (i = 0; i < ARRAY_SIZE(xfrm_policy_afinfo); i++) {
+		if (xfrm_policy_afinfo[i] != afinfo)
+			continue;
+		RCU_INIT_POINTER(xfrm_policy_afinfo[i], NULL);
+		break;
 	}
 
 	synchronize_rcu();

From bdba9fe01e1bcb942c95a1a332b27ef829c87df4 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:18 +0100
Subject: [PATCH 06/13] xfrm: policy: remove xfrm_policy_put_afinfo

Alternative is to keep it an make the (unused) afinfo arg const to avoid
the compiler warnings once the afinfo structs get constified.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/xfrm/xfrm_policy.c | 21 ++++++++-------------
 1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 7698785876d7..80ef0dcf0e29 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -116,11 +116,6 @@ static const struct xfrm_policy_afinfo *xfrm_policy_get_afinfo(unsigned short fa
 	return afinfo;
 }
 
-static void xfrm_policy_put_afinfo(struct xfrm_policy_afinfo *afinfo)
-{
-	rcu_read_unlock();
-}
-
 static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
 						  int tos, int oif,
 						  const xfrm_address_t *saddr,
@@ -136,7 +131,7 @@ static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
 
 	dst = afinfo->dst_lookup(net, tos, oif, saddr, daddr);
 
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return dst;
 }
@@ -1436,7 +1431,7 @@ xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
 	if (unlikely(afinfo == NULL))
 		return -EINVAL;
 	err = afinfo->get_saddr(net, oif, local, remote);
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 	return err;
 }
 
@@ -1546,7 +1541,7 @@ static int xfrm_get_tos(const struct flowi *fl, int family)
 	afinfo = xfrm_policy_get_afinfo(family);
 	tos = afinfo ? afinfo->get_tos(fl) : 0;
 
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return tos;
 }
@@ -1632,7 +1627,7 @@ static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
 	} else
 		xdst = ERR_PTR(-ENOBUFS);
 
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return xdst;
 }
@@ -1649,7 +1644,7 @@ static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
 
 	err = afinfo->init_path(path, dst, nfheader_len);
 
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return err;
 }
@@ -1666,7 +1661,7 @@ static inline int xfrm_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
 
 	err = afinfo->fill_dst(xdst, dev, fl);
 
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return err;
 }
@@ -2215,7 +2210,7 @@ static struct dst_entry *make_blackhole(struct net *net, u16 family,
 	} else {
 		ret = afinfo->blackhole_route(net, dst_orig);
 	}
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 
 	return ret;
 }
@@ -2465,7 +2460,7 @@ int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
 
 	afinfo->decode_session(skb, fl, reverse);
 	err = security_xfrm_decode_session(skb, &fl->flowi_secid);
-	xfrm_policy_put_afinfo(afinfo);
+	rcu_read_unlock();
 	return err;
 }
 EXPORT_SYMBOL(__xfrm_decode_session);

From 37b103830ec3e52a761bb647eb78da22a1fe4e09 Mon Sep 17 00:00:00 2001
From: Florian Westphal <fw@strlen.de>
Date: Tue, 7 Feb 2017 15:00:19 +0100
Subject: [PATCH 07/13] xfrm: policy: make policy backend const

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 net/ipv4/xfrm4_policy.c |  2 +-
 net/ipv6/xfrm6_policy.c |  2 +-
 net/xfrm/xfrm_policy.c  | 18 +++++++++---------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 25613539766f..71b4ecc195c7 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -269,7 +269,7 @@ static struct dst_ops xfrm4_dst_ops_template = {
 	.gc_thresh =		INT_MAX,
 };
 
-static struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
+static const struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
 	.dst_ops =		&xfrm4_dst_ops_template,
 	.dst_lookup =		xfrm4_dst_lookup,
 	.get_saddr =		xfrm4_get_saddr,
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 3217e85334e3..79651bc71bf0 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -289,7 +289,7 @@ static struct dst_ops xfrm6_dst_ops_template = {
 	.gc_thresh =		INT_MAX,
 };
 
-static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
+static const struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
 	.dst_ops =		&xfrm6_dst_ops_template,
 	.dst_lookup =		xfrm6_dst_lookup,
 	.get_saddr =		xfrm6_get_saddr,
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 80ef0dcf0e29..04ed1a1ae019 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -45,7 +45,7 @@ struct xfrm_flo {
 };
 
 static DEFINE_SPINLOCK(xfrm_policy_afinfo_lock);
-static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
+static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
 						__read_mostly;
 
 static struct kmem_cache *xfrm_dst_cache __read_mostly;
@@ -122,7 +122,7 @@ static inline struct dst_entry *__xfrm_dst_lookup(struct net *net,
 						  const xfrm_address_t *daddr,
 						  int family)
 {
-	struct xfrm_policy_afinfo *afinfo;
+	const struct xfrm_policy_afinfo *afinfo;
 	struct dst_entry *dst;
 
 	afinfo = xfrm_policy_get_afinfo(family);
@@ -1426,7 +1426,7 @@ xfrm_get_saddr(struct net *net, int oif, xfrm_address_t *local,
 	       xfrm_address_t *remote, unsigned short family)
 {
 	int err;
-	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 
 	if (unlikely(afinfo == NULL))
 		return -EINVAL;
@@ -1535,7 +1535,7 @@ xfrm_tmpl_resolve(struct xfrm_policy **pols, int npols, const struct flowi *fl,
 
 static int xfrm_get_tos(const struct flowi *fl, int family)
 {
-	struct xfrm_policy_afinfo *afinfo;
+	const struct xfrm_policy_afinfo *afinfo;
 	int tos = 0;
 
 	afinfo = xfrm_policy_get_afinfo(family);
@@ -1598,7 +1598,7 @@ static const struct flow_cache_ops xfrm_bundle_fc_ops = {
 
 static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
 {
-	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 	struct dst_ops *dst_ops;
 	struct xfrm_dst *xdst;
 
@@ -1635,7 +1635,7 @@ static inline struct xfrm_dst *xfrm_alloc_dst(struct net *net, int family)
 static inline int xfrm_init_path(struct xfrm_dst *path, struct dst_entry *dst,
 				 int nfheader_len)
 {
-	struct xfrm_policy_afinfo *afinfo =
+	const struct xfrm_policy_afinfo *afinfo =
 		xfrm_policy_get_afinfo(dst->ops->family);
 	int err;
 
@@ -1652,7 +1652,7 @@ 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,
 				const struct flowi *fl)
 {
-	struct xfrm_policy_afinfo *afinfo =
+	const struct xfrm_policy_afinfo *afinfo =
 		xfrm_policy_get_afinfo(xdst->u.dst.ops->family);
 	int err;
 
@@ -2201,7 +2201,7 @@ error:
 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);
+	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 	struct dst_entry *ret;
 
 	if (!afinfo) {
@@ -2452,7 +2452,7 @@ xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int star
 int __xfrm_decode_session(struct sk_buff *skb, struct flowi *fl,
 			  unsigned int family, int reverse)
 {
-	struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
+	const struct xfrm_policy_afinfo *afinfo = xfrm_policy_get_afinfo(family);
 	int err;
 
 	if (unlikely(afinfo == NULL))

From b0fcee825c0ad05057a97d1f4685e1b9e9d00c53 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:39:24 +0100
Subject: [PATCH 08/13] xfrm: Add a secpath_set helper.

Add a new helper to set the secpath to the skb.
This avoids code duplication, as this is used
in multiple places.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h     |  1 +
 net/ipv6/xfrm6_input.c | 15 +++------------
 net/xfrm/xfrm_input.c  | 34 ++++++++++++++++++++++------------
 3 files changed, 26 insertions(+), 24 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 6e061309adca..287635df4eef 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1006,6 +1006,7 @@ secpath_put(struct sec_path *sp)
 }
 
 struct sec_path *secpath_dup(struct sec_path *src);
+int secpath_set(struct sk_buff *skb);
 
 static inline void
 secpath_reset(struct sk_buff *skb)
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index b5789562aded..662fb2c3e765 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -69,18 +69,9 @@ int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
 	struct xfrm_state *x = NULL;
 	int i = 0;
 
-	/* Allocate new secpath or COW existing one. */
-	if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
-		struct sec_path *sp;
-
-		sp = secpath_dup(skb->sp);
-		if (!sp) {
-			XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
-			goto drop;
-		}
-		if (skb->sp)
-			secpath_put(skb->sp);
-		skb->sp = sp;
+	if (secpath_set(skb)) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+		goto drop;
 	}
 
 	if (1 + skb->sp->len == XFRM_MAX_DEPTH) {
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 8722294c6e59..d8f913bb6919 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -117,6 +117,24 @@ struct sec_path *secpath_dup(struct sec_path *src)
 }
 EXPORT_SYMBOL(secpath_dup);
 
+int secpath_set(struct sk_buff *skb)
+{
+	struct sec_path *sp;
+
+	/* Allocate new secpath or COW existing one. */
+	if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
+		sp = secpath_dup(skb->sp);
+		if (!sp)
+			return -ENOMEM;
+
+		if (skb->sp)
+			secpath_put(skb->sp);
+		skb->sp = sp;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(secpath_set);
+
 /* Fetch spi and seq from ipsec header */
 
 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
@@ -212,18 +230,10 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 		break;
 	}
 
-	/* Allocate new secpath or COW existing one. */
-	if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
-		struct sec_path *sp;
-
-		sp = secpath_dup(skb->sp);
-		if (!sp) {
-			XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
-			goto drop;
-		}
-		if (skb->sp)
-			secpath_put(skb->sp);
-		skb->sp = sp;
+	err = secpath_set(skb);
+	if (err) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+		goto drop;
 	}
 
 	seq = 0;

From 5f114163f2f5eb2edbb49c4d3e0b405c7a8a7e2a Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:39:39 +0100
Subject: [PATCH 09/13] net: Add a skb_gro_flush_final helper.

Add a skb_gro_flush_final helper to prepare for  consuming
skbs in call_gro_receive. We will extend this helper to not
touch the skb if the skb is consumed by a gro callback with
a followup patch. We need this to handle the upcomming IPsec
ESP callbacks as they reinject the skb to the napi_gro_receive
asynchronous. The handler is used in all gro_receive functions
that can call the ESP gro handlers.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/linux/netdevice.h | 5 +++++
 net/ethernet/eth.c        | 2 +-
 net/ipv4/af_inet.c        | 2 +-
 net/ipv6/ip6_offload.c    | 2 +-
 4 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 58afbd1cc659..f9da3acfee9a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2661,6 +2661,11 @@ static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
 	remcsum_unadjust((__sum16 *)ptr, grc->delta);
 }
 
+static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff **pp, int flush)
+{
+	NAPI_GRO_CB(skb)->flush |= flush;
+}
+
 static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
 				  unsigned short type,
 				  const void *daddr, const void *saddr,
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index efdaaab735fc..c666ff0dd88b 100644
--- a/net/ethernet/eth.c
+++ b/net/ethernet/eth.c
@@ -474,7 +474,7 @@ struct sk_buff **eth_gro_receive(struct sk_buff **head,
 out_unlock:
 	rcu_read_unlock();
 out:
-	NAPI_GRO_CB(skb)->flush |= flush;
+	skb_gro_flush_final(skb, pp, flush);
 
 	return pp;
 }
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 685ba53df2d1..602d40f43687 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1423,7 +1423,7 @@ out_unlock:
 	rcu_read_unlock();
 
 out:
-	NAPI_GRO_CB(skb)->flush |= flush;
+	skb_gro_flush_final(skb, pp, flush);
 
 	return pp;
 }
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index fc7b4017ba24..0838e6d01d2e 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -253,7 +253,7 @@ out_unlock:
 	rcu_read_unlock();
 
 out:
-	NAPI_GRO_CB(skb)->flush |= flush;
+	skb_gro_flush_final(skb, pp, flush);
 
 	return pp;
 }

From 25393d3fc055b76587fcc91627aee8c345400c3a Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:39:44 +0100
Subject: [PATCH 10/13] net: Prepare gro for packet consuming gro callbacks

The upcomming IPsec ESP gro callbacks will consume the skb,
so prepare for that.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/linux/netdevice.h | 9 +++++++++
 net/core/dev.c            | 7 +++++++
 net/xfrm/Kconfig          | 4 ++++
 3 files changed, 20 insertions(+)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index f9da3acfee9a..9e5d1cd9d975 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -352,6 +352,7 @@ enum gro_result {
 	GRO_HELD,
 	GRO_NORMAL,
 	GRO_DROP,
+	GRO_CONSUMED,
 };
 typedef enum gro_result gro_result_t;
 
@@ -2661,10 +2662,18 @@ static inline void skb_gro_remcsum_cleanup(struct sk_buff *skb,
 	remcsum_unadjust((__sum16 *)ptr, grc->delta);
 }
 
+#ifdef CONFIG_XFRM_OFFLOAD
+static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff **pp, int flush)
+{
+	if (PTR_ERR(pp) != -EINPROGRESS)
+		NAPI_GRO_CB(skb)->flush |= flush;
+}
+#else
 static inline void skb_gro_flush_final(struct sk_buff *skb, struct sk_buff **pp, int flush)
 {
 	NAPI_GRO_CB(skb)->flush |= flush;
 }
+#endif
 
 static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
 				  unsigned short type,
diff --git a/net/core/dev.c b/net/core/dev.c
index 3e1a60102e64..64efbb9e4436 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4505,6 +4505,11 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 	if (&ptype->list == head)
 		goto normal;
 
+	if (IS_ERR(pp) && PTR_ERR(pp) == -EINPROGRESS) {
+		ret = GRO_CONSUMED;
+		goto ok;
+	}
+
 	same_flow = NAPI_GRO_CB(skb)->same_flow;
 	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
 
@@ -4609,6 +4614,7 @@ static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
 
 	case GRO_HELD:
 	case GRO_MERGED:
+	case GRO_CONSUMED:
 		break;
 	}
 
@@ -4680,6 +4686,7 @@ static gro_result_t napi_frags_finish(struct napi_struct *napi,
 		break;
 
 	case GRO_MERGED:
+	case GRO_CONSUMED:
 		break;
 	}
 
diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig
index bda1a13628a8..a484451c72ec 100644
--- a/net/xfrm/Kconfig
+++ b/net/xfrm/Kconfig
@@ -5,6 +5,10 @@ config XFRM
        bool
        depends on NET
 
+config XFRM_OFFLOAD
+       bool
+       depends on XFRM
+
 config XFRM_ALGO
 	tristate
 	select XFRM

From 1e29537034e388c7e72eac43cfcda1d23131623b Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:39:49 +0100
Subject: [PATCH 11/13] xfrm: Export xfrm_parse_spi.

We need it in the ESP offload handlers, so export it.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h    | 1 +
 net/xfrm/xfrm_input.c | 1 +
 2 files changed, 2 insertions(+)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 287635df4eef..fe8db3d87e4f 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1520,6 +1520,7 @@ int xfrm4_rcv_encap(struct sk_buff *skb, int nexthdr, __be32 spi,
 		    int encap_type);
 int xfrm4_transport_finish(struct sk_buff *skb, int async);
 int xfrm4_rcv(struct sk_buff *skb);
+int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq);
 
 static inline int xfrm4_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi)
 {
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index d8f913bb6919..86f8a8de5252 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -170,6 +170,7 @@ int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 	*seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
 	return 0;
 }
+EXPORT_SYMBOL(xfrm_parse_spi);
 
 int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 {

From 54ef207ac8f7a17d677082157a29f4df8499dc81 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:39:54 +0100
Subject: [PATCH 12/13] xfrm: Extend the sec_path for IPsec offloading

We need to keep per packet offloading informations across
the layers. So we extend the sec_path to carry these for
the input and output offload codepath.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h    | 41 +++++++++++++++++++++++++++++++++++++++++
 net/xfrm/xfrm_input.c |  2 ++
 2 files changed, 43 insertions(+)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index fe8db3d87e4f..10086a0986f8 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -498,6 +498,7 @@ struct xfrm_tmpl {
 };
 
 #define XFRM_MAX_DEPTH		6
+#define XFRM_MAX_OFFLOAD_DEPTH	1
 
 struct xfrm_policy_walk_entry {
 	struct list_head	all;
@@ -973,10 +974,41 @@ static inline void xfrm_dst_destroy(struct xfrm_dst *xdst)
 
 void xfrm_dst_ifdown(struct dst_entry *dst, struct net_device *dev);
 
+struct xfrm_offload {
+	/* Output sequence number for replay protection on offloading. */
+	struct {
+		__u32 low;
+		__u32 hi;
+	} seq;
+
+	__u32			flags;
+#define	SA_DELETE_REQ		1
+#define	CRYPTO_DONE		2
+#define	CRYPTO_NEXT_DONE	4
+#define	CRYPTO_FALLBACK		8
+#define	XFRM_GSO_SEGMENT	16
+#define	XFRM_GRO		32
+
+	__u32			status;
+#define CRYPTO_SUCCESS				1
+#define CRYPTO_GENERIC_ERROR			2
+#define CRYPTO_TRANSPORT_AH_AUTH_FAILED		4
+#define CRYPTO_TRANSPORT_ESP_AUTH_FAILED	8
+#define CRYPTO_TUNNEL_AH_AUTH_FAILED		16
+#define CRYPTO_TUNNEL_ESP_AUTH_FAILED		32
+#define CRYPTO_INVALID_PACKET_SYNTAX		64
+#define CRYPTO_INVALID_PROTOCOL			128
+
+	__u8			proto;
+};
+
 struct sec_path {
 	atomic_t		refcnt;
 	int			len;
+	int			olen;
+
 	struct xfrm_state	*xvec[XFRM_MAX_DEPTH];
+	struct xfrm_offload	ovec[XFRM_MAX_OFFLOAD_DEPTH];
 };
 
 static inline int secpath_exists(struct sk_buff *skb)
@@ -1776,6 +1808,15 @@ static inline struct xfrm_state *xfrm_input_state(struct sk_buff *skb)
 {
 	return skb->sp->xvec[skb->sp->len - 1];
 }
+static inline struct xfrm_offload *xfrm_offload(struct sk_buff *skb)
+{
+	struct sec_path *sp = skb->sp;
+
+	if (!sp || !sp->olen || sp->len != sp->olen)
+		return NULL;
+
+	return &sp->ovec[sp->olen - 1];
+}
 #endif
 
 static inline int xfrm_mark_get(struct nlattr **attrs, struct xfrm_mark *m)
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 86f8a8de5252..d2ff71230864 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -105,6 +105,8 @@ struct sec_path *secpath_dup(struct sec_path *src)
 		return NULL;
 
 	sp->len = 0;
+	sp->olen = 0;
+
 	if (src) {
 		int i;
 

From 7785bba299a8dc8fe8390a0183dad3cafb3f1d80 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Wed, 15 Feb 2017 09:40:00 +0100
Subject: [PATCH 13/13] esp: Add a software GRO codepath

This patch adds GRO ifrastructure and callbacks for ESP on
ipv4 and ipv6.

In case the GRO layer detects an ESP packet, the
esp{4,6}_gro_receive() function does a xfrm state lookup
and calls the xfrm input layer if it finds a matching state.
The packet will be decapsulated and reinjected it into layer 2.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
---
 include/net/xfrm.h              |   1 +
 net/ipv4/Kconfig                |  13 ++++
 net/ipv4/Makefile               |   1 +
 net/ipv4/esp4_offload.c         | 106 +++++++++++++++++++++++++++++++
 net/ipv4/xfrm4_input.c          |   6 ++
 net/ipv4/xfrm4_mode_transport.c |   4 +-
 net/ipv6/Kconfig                |  13 ++++
 net/ipv6/Makefile               |   1 +
 net/ipv6/esp6_offload.c         | 108 ++++++++++++++++++++++++++++++++
 net/ipv6/xfrm6_input.c          |   7 +++
 net/ipv6/xfrm6_mode_transport.c |   4 +-
 net/xfrm/xfrm_input.c           |  31 +++++++--
 12 files changed, 288 insertions(+), 7 deletions(-)
 create mode 100644 net/ipv4/esp4_offload.c
 create mode 100644 net/ipv6/esp6_offload.c

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 10086a0986f8..14d82bf16692 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -682,6 +682,7 @@ struct xfrm_spi_skb_cb {
 
 	unsigned int daddroff;
 	unsigned int family;
+	__be32 seq;
 };
 
 #define XFRM_SPI_SKB_CB(__skb) ((struct xfrm_spi_skb_cb *)&((__skb)->cb[0]))
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 6e7baaf814c6..e0878c3f66a8 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -360,6 +360,19 @@ config INET_ESP
 
 	  If unsure, say Y.
 
+config INET_ESP_OFFLOAD
+	tristate "IP: ESP transformation offload"
+	depends on INET_ESP
+	select XFRM_OFFLOAD
+	default n
+	---help---
+	  Support for ESP transformation offload. This makes sense
+	  only if this system really does IPsec and want to do it
+	  with high throughput. A typical desktop system does not
+	  need it, even if it does IPsec.
+
+	  If unsure, say N.
+
 config INET_IPCOMP
 	tristate "IP: IPComp transformation"
 	select INET_XFRM_TUNNEL
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 48af58a5686e..c6d4238ff94a 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_NET_IPVTI) += ip_vti.o
 obj-$(CONFIG_SYN_COOKIES) += syncookies.o
 obj-$(CONFIG_INET_AH) += ah4.o
 obj-$(CONFIG_INET_ESP) += esp4.o
+obj-$(CONFIG_INET_ESP_OFFLOAD) += esp4_offload.o
 obj-$(CONFIG_INET_IPCOMP) += ipcomp.o
 obj-$(CONFIG_INET_XFRM_TUNNEL) += xfrm4_tunnel.o
 obj-$(CONFIG_INET_XFRM_MODE_BEET) += xfrm4_mode_beet.o
diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c
new file mode 100644
index 000000000000..1de442632406
--- /dev/null
+++ b/net/ipv4/esp4_offload.c
@@ -0,0 +1,106 @@
+/*
+ * IPV4 GSO/GRO offload support
+ * Linux INET implementation
+ *
+ * Copyright (C) 2016 secunet Security Networks AG
+ * Author: Steffen Klassert <steffen.klassert@secunet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * ESP GRO support
+ */
+
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <net/protocol.h>
+#include <crypto/aead.h>
+#include <crypto/authenc.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <net/ip.h>
+#include <net/xfrm.h>
+#include <net/esp.h>
+#include <linux/scatterlist.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <net/udp.h>
+
+static struct sk_buff **esp4_gro_receive(struct sk_buff **head,
+					 struct sk_buff *skb)
+{
+	int offset = skb_gro_offset(skb);
+	struct xfrm_offload *xo;
+	struct xfrm_state *x;
+	__be32 seq;
+	__be32 spi;
+	int err;
+
+	skb_pull(skb, offset);
+
+	if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
+		goto out;
+
+	err = secpath_set(skb);
+	if (err)
+		goto out;
+
+	if (skb->sp->len == XFRM_MAX_DEPTH)
+		goto out;
+
+	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
+			      (xfrm_address_t *)&ip_hdr(skb)->daddr,
+			      spi, IPPROTO_ESP, AF_INET);
+	if (!x)
+		goto out;
+
+	skb->sp->xvec[skb->sp->len++] = x;
+	skb->sp->olen++;
+
+	xo = xfrm_offload(skb);
+	if (!xo) {
+		xfrm_state_put(x);
+		goto out;
+	}
+	xo->flags |= XFRM_GRO;
+
+	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
+	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
+	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
+	XFRM_SPI_SKB_CB(skb)->seq = seq;
+
+	/* We don't need to handle errors from xfrm_input, it does all
+	 * the error handling and frees the resources on error. */
+	xfrm_input(skb, IPPROTO_ESP, spi, -2);
+
+	return ERR_PTR(-EINPROGRESS);
+out:
+	skb_push(skb, offset);
+	NAPI_GRO_CB(skb)->same_flow = 0;
+	NAPI_GRO_CB(skb)->flush = 1;
+
+	return NULL;
+}
+
+static const struct net_offload esp4_offload = {
+	.callbacks = {
+		.gro_receive = esp4_gro_receive,
+	},
+};
+
+static int __init esp4_offload_init(void)
+{
+	return inet_add_offload(&esp4_offload, IPPROTO_ESP);
+}
+
+static void __exit esp4_offload_exit(void)
+{
+	inet_del_offload(&esp4_offload, IPPROTO_ESP);
+}
+
+module_init(esp4_offload_init);
+module_exit(esp4_offload_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index 62e1e72db461..1fc684111ce6 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -40,6 +40,7 @@ drop:
 
 int xfrm4_transport_finish(struct sk_buff *skb, int async)
 {
+	struct xfrm_offload *xo = xfrm_offload(skb);
 	struct iphdr *iph = ip_hdr(skb);
 
 	iph->protocol = XFRM_MODE_SKB_CB(skb)->protocol;
@@ -53,6 +54,11 @@ int xfrm4_transport_finish(struct sk_buff *skb, int async)
 	iph->tot_len = htons(skb->len);
 	ip_send_check(iph);
 
+	if (xo && (xo->flags & XFRM_GRO)) {
+		skb_mac_header_rebuild(skb);
+		return 0;
+	}
+
 	NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING,
 		dev_net(skb->dev), NULL, skb, skb->dev, NULL,
 		xfrm4_rcv_encap_finish);
diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c
index fd840c7d75ea..4acc0508c5eb 100644
--- a/net/ipv4/xfrm4_mode_transport.c
+++ b/net/ipv4/xfrm4_mode_transport.c
@@ -43,6 +43,7 @@ static int xfrm4_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
+	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -50,7 +51,8 @@ static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 		skb->network_header = skb->transport_header;
 	}
 	ip_hdr(skb)->tot_len = htons(skb->len + ihl);
-	skb_reset_transport_header(skb);
+	if (!xo || !(xo->flags & XFRM_GRO))
+		skb_reset_transport_header(skb);
 	return 0;
 }
 
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index ec1267e2bd1f..b2a85cca91f7 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -75,6 +75,19 @@ config INET6_ESP
 
 	  If unsure, say Y.
 
+config INET6_ESP_OFFLOAD
+	tristate "IPv6: ESP transformation offload"
+	depends on INET6_ESP
+	select XFRM_OFFLOAD
+	default n
+	---help---
+	  Support for ESP transformation offload. This makes sense
+	  only if this system really does IPsec and want to do it
+	  with high throughput. A typical desktop system does not
+	  need it, even if it does IPsec.
+
+	  If unsure, say N.
+
 config INET6_IPCOMP
 	tristate "IPv6: IPComp transformation"
 	select INET6_XFRM_TUNNEL
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index a9e9fec387ce..217e9ff0e24b 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -30,6 +30,7 @@ ipv6-objs += $(ipv6-y)
 
 obj-$(CONFIG_INET6_AH) += ah6.o
 obj-$(CONFIG_INET6_ESP) += esp6.o
+obj-$(CONFIG_INET6_ESP_OFFLOAD) += esp6_offload.o
 obj-$(CONFIG_INET6_IPCOMP) += ipcomp6.o
 obj-$(CONFIG_INET6_XFRM_TUNNEL) += xfrm6_tunnel.o
 obj-$(CONFIG_INET6_TUNNEL) += tunnel6.o
diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
new file mode 100644
index 000000000000..d914eb93204a
--- /dev/null
+++ b/net/ipv6/esp6_offload.c
@@ -0,0 +1,108 @@
+/*
+ * IPV6 GSO/GRO offload support
+ * Linux INET implementation
+ *
+ * Copyright (C) 2016 secunet Security Networks AG
+ * Author: Steffen Klassert <steffen.klassert@secunet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * ESP GRO support
+ */
+
+#include <linux/skbuff.h>
+#include <linux/init.h>
+#include <net/protocol.h>
+#include <crypto/aead.h>
+#include <crypto/authenc.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <net/ip.h>
+#include <net/xfrm.h>
+#include <net/esp.h>
+#include <linux/scatterlist.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <net/ip6_route.h>
+#include <net/ipv6.h>
+#include <linux/icmpv6.h>
+
+static struct sk_buff **esp6_gro_receive(struct sk_buff **head,
+					 struct sk_buff *skb)
+{
+	int offset = skb_gro_offset(skb);
+	struct xfrm_offload *xo;
+	struct xfrm_state *x;
+	__be32 seq;
+	__be32 spi;
+	int err;
+
+	skb_pull(skb, offset);
+
+	if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
+		goto out;
+
+	err = secpath_set(skb);
+	if (err)
+		goto out;
+
+	if (skb->sp->len == XFRM_MAX_DEPTH)
+		goto out;
+
+	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
+			      (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
+			      spi, IPPROTO_ESP, AF_INET6);
+	if (!x)
+		goto out;
+
+	skb->sp->xvec[skb->sp->len++] = x;
+	skb->sp->olen++;
+
+	xo = xfrm_offload(skb);
+	if (!xo) {
+		xfrm_state_put(x);
+		goto out;
+	}
+	xo->flags |= XFRM_GRO;
+
+	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL;
+	XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
+	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
+	XFRM_SPI_SKB_CB(skb)->seq = seq;
+
+	/* We don't need to handle errors from xfrm_input, it does all
+	 * the error handling and frees the resources on error. */
+	xfrm_input(skb, IPPROTO_ESP, spi, -2);
+
+	return ERR_PTR(-EINPROGRESS);
+out:
+	skb_push(skb, offset);
+	NAPI_GRO_CB(skb)->same_flow = 0;
+	NAPI_GRO_CB(skb)->flush = 1;
+
+	return NULL;
+}
+
+static const struct net_offload esp6_offload = {
+	.callbacks = {
+		.gro_receive = esp6_gro_receive,
+	},
+};
+
+static int __init esp6_offload_init(void)
+{
+	return inet6_add_offload(&esp6_offload, IPPROTO_ESP);
+}
+
+static void __exit esp6_offload_exit(void)
+{
+	inet6_del_offload(&esp6_offload, IPPROTO_ESP);
+}
+
+module_init(esp6_offload_init);
+module_exit(esp6_offload_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 662fb2c3e765..08a807b29298 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -33,6 +33,8 @@ EXPORT_SYMBOL(xfrm6_rcv_spi);
 
 int xfrm6_transport_finish(struct sk_buff *skb, int async)
 {
+	struct xfrm_offload *xo = xfrm_offload(skb);
+
 	skb_network_header(skb)[IP6CB(skb)->nhoff] =
 		XFRM_MODE_SKB_CB(skb)->protocol;
 
@@ -44,6 +46,11 @@ int xfrm6_transport_finish(struct sk_buff *skb, int async)
 	ipv6_hdr(skb)->payload_len = htons(skb->len);
 	__skb_push(skb, skb->data - skb_network_header(skb));
 
+	if (xo && (xo->flags & XFRM_GRO)) {
+		skb_mac_header_rebuild(skb);
+		return -1;
+	}
+
 	NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
 		dev_net(skb->dev), NULL, skb, skb->dev, NULL,
 		ip6_rcv_finish);
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c
index 4e344105b3fd..4439ee44c8b0 100644
--- a/net/ipv6/xfrm6_mode_transport.c
+++ b/net/ipv6/xfrm6_mode_transport.c
@@ -47,6 +47,7 @@ static int xfrm6_transport_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int ihl = skb->data - skb_transport_header(skb);
+	struct xfrm_offload *xo = xfrm_offload(skb);
 
 	if (skb->transport_header != skb->network_header) {
 		memmove(skb_transport_header(skb),
@@ -55,7 +56,8 @@ static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 	}
 	ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 					   sizeof(struct ipv6hdr));
-	skb_reset_transport_header(skb);
+	if (!xo || !(xo->flags & XFRM_GRO))
+		skb_reset_transport_header(skb);
 	return 0;
 }
 
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index d2ff71230864..46bdb4fbed0b 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -207,14 +207,23 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 	unsigned int family;
 	int decaps = 0;
 	int async = 0;
+	struct xfrm_offload *xo;
+	bool xfrm_gro = false;
 
-	/* A negative encap_type indicates async resumption. */
 	if (encap_type < 0) {
-		async = 1;
 		x = xfrm_input_state(skb);
-		seq = XFRM_SKB_CB(skb)->seq.input.low;
 		family = x->outer_mode->afinfo->family;
-		goto resume;
+
+		/* An encap_type of -1 indicates async resumption. */
+		if (encap_type == -1) {
+			async = 1;
+			seq = XFRM_SKB_CB(skb)->seq.input.low;
+			goto resume;
+		}
+		/* encap_type < -1 indicates a GRO call. */
+		encap_type = 0;
+		seq = XFRM_SPI_SKB_CB(skb)->seq;
+		goto lock;
 	}
 
 	daddr = (xfrm_address_t *)(skb_network_header(skb) +
@@ -260,6 +269,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		skb->sp->xvec[skb->sp->len++] = x;
 
+lock:
 		spin_lock(&x->lock);
 
 		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
@@ -381,7 +391,18 @@ resume:
 		gro_cells_receive(&gro_cells, skb);
 		return 0;
 	} else {
-		return x->inner_mode->afinfo->transport_finish(skb, async);
+		xo = xfrm_offload(skb);
+		if (xo)
+			xfrm_gro = xo->flags & XFRM_GRO;
+
+		err = x->inner_mode->afinfo->transport_finish(skb, async);
+		if (xfrm_gro) {
+			skb_dst_drop(skb);
+			gro_cells_receive(&gro_cells, skb);
+			return err;
+		}
+
+		return err;
 	}
 
 drop_unlock: