Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Conflicts:
	net/netfilter/core.c
	net/netfilter/nf_tables_netdev.c

Resolve two conflicts before pull request for David's net-next tree:

1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant
   ip_hdr assignment") from the net tree and commit ddc8b6027ad0
   ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").

2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and
   Aaron Conole's patches to replace list_head with single linked list.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

40 files changed, 1779 insertions, 395 deletions

diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 50d6a9b49f6c..300b06888fdf 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -640,6 +640,21 @@ config TCP_CONG_CDG
 	  D.A. Hayes and G. Armitage. "Revisiting TCP congestion control using
 	  delay gradients." In Networking 2011. Preprint: http://goo.gl/No3vdg
 
+config TCP_CONG_BBR
+	tristate "BBR TCP"
+	default n
+	---help---
+
+	BBR (Bottleneck Bandwidth and RTT) TCP congestion control aims to
+	maximize network utilization and minimize queues. It builds an explicit
+	model of the the bottleneck delivery rate and path round-trip
+	propagation delay. It tolerates packet loss and delay unrelated to
+	congestion. It can operate over LAN, WAN, cellular, wifi, or cable
+	modem links. It can coexist with flows that use loss-based congestion
+	control, and can operate with shallow buffers, deep buffers,
+	bufferbloat, policers, or AQM schemes that do not provide a delay
+	signal. It requires the fq ("Fair Queue") pacing packet scheduler.
+
 choice
 	prompt "Default TCP congestion control"
 	default DEFAULT_CUBIC
@@ -674,6 +689,9 @@ choice
 	config DEFAULT_CDG
 		bool "CDG" if TCP_CONG_CDG=y
 
+	config DEFAULT_BBR
+		bool "BBR" if TCP_CONG_BBR=y
+
 	config DEFAULT_RENO
 		bool "Reno"
 endchoice
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 24629b6f57cc..bc6a6c8b9bcd 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -8,7 +8,7 @@ obj-y     := route.o inetpeer.o protocol.o \
 	     inet_timewait_sock.o inet_connection_sock.o \
 	     tcp.o tcp_input.o tcp_output.o tcp_timer.o tcp_ipv4.o \
 	     tcp_minisocks.o tcp_cong.o tcp_metrics.o tcp_fastopen.o \
-	     tcp_recovery.o \
+	     tcp_rate.o tcp_recovery.o \
 	     tcp_offload.o datagram.o raw.o udp.o udplite.o \
 	     udp_offload.o arp.o icmp.o devinet.o af_inet.o igmp.o \
 	     fib_frontend.o fib_semantics.o fib_trie.o \
@@ -41,6 +41,7 @@ obj-$(CONFIG_INET_DIAG) += inet_diag.o
 obj-$(CONFIG_INET_TCP_DIAG) += tcp_diag.o
 obj-$(CONFIG_INET_UDP_DIAG) += udp_diag.o
 obj-$(CONFIG_NET_TCPPROBE) += tcp_probe.o
+obj-$(CONFIG_TCP_CONG_BBR) += tcp_bbr.o
 obj-$(CONFIG_TCP_CONG_BIC) += tcp_bic.o
 obj-$(CONFIG_TCP_CONG_CDG) += tcp_cdg.o
 obj-$(CONFIG_TCP_CONG_CUBIC) += tcp_cubic.o
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index e94b47be0019..1effc986739e 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1192,7 +1192,7 @@ EXPORT_SYMBOL(inet_sk_rebuild_header);
 struct sk_buff *inet_gso_segment(struct sk_buff *skb,
 				 netdev_features_t features)
 {
-	bool udpfrag = false, fixedid = false, encap;
+	bool udpfrag = false, fixedid = false, gso_partial, encap;
 	struct sk_buff *segs = ERR_PTR(-EINVAL);
 	const struct net_offload *ops;
 	unsigned int offset = 0;
@@ -1245,6 +1245,8 @@ struct sk_buff *inet_gso_segment(struct sk_buff *skb,
 	if (IS_ERR_OR_NULL(segs))
 		goto out;
 
+	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
+
 	skb = segs;
 	do {
 		iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
@@ -1259,9 +1261,13 @@ struct sk_buff *inet_gso_segment(struct sk_buff *skb,
 				iph->id = htons(id);
 				id += skb_shinfo(skb)->gso_segs;
 			}
-			tot_len = skb_shinfo(skb)->gso_size +
-				  SKB_GSO_CB(skb)->data_offset +
-				  skb->head - (unsigned char *)iph;
+
+			if (gso_partial)
+				tot_len = skb_shinfo(skb)->gso_size +
+					  SKB_GSO_CB(skb)->data_offset +
+					  skb->head - (unsigned char *)iph;
+			else
+				tot_len = skb->len - nhoff;
 		} else {
 			if (!fixedid)
 				iph->id = htons(id++);
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 415e117967c7..062a67ca9a21 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -2232,7 +2232,7 @@ static struct devinet_sysctl_table {
 };
 
 static int __devinet_sysctl_register(struct net *net, char *dev_name,
-					struct ipv4_devconf *p)
+				     int ifindex, struct ipv4_devconf *p)
 {
 	int i;
 	struct devinet_sysctl_table *t;
@@ -2255,6 +2255,8 @@ static int __devinet_sysctl_register(struct net *net, char *dev_name,
 		goto free;
 
 	p->sysctl = t;
+
+	inet_netconf_notify_devconf(net, NETCONFA_ALL, ifindex, p);
 	return 0;
 
 free:
@@ -2286,7 +2288,7 @@ static int devinet_sysctl_register(struct in_device *idev)
 	if (err)
 		return err;
 	err = __devinet_sysctl_register(dev_net(idev->dev), idev->dev->name,
-					&idev->cnf);
+					idev->dev->ifindex, &idev->cnf);
 	if (err)
 		neigh_sysctl_unregister(idev->arp_parms);
 	return err;
@@ -2347,11 +2349,12 @@ static __net_init int devinet_init_net(struct net *net)
 	}
 
 #ifdef CONFIG_SYSCTL
-	err = __devinet_sysctl_register(net, "all", all);
+	err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all);
 	if (err < 0)
 		goto err_reg_all;
 
-	err = __devinet_sysctl_register(net, "default", dflt);
+	err = __devinet_sysctl_register(net, "default",
+					NETCONFA_IFINDEX_DEFAULT, dflt);
 	if (err < 0)
 		goto err_reg_dflt;
 
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 317c31939732..4e56a4c20a3c 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -503,6 +503,7 @@ static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt,
 		if (!dev)
 			return -ENODEV;
 		cfg->fc_oif = dev->ifindex;
+		cfg->fc_table = l3mdev_fib_table(dev);
 		if (colon) {
 			struct in_ifaddr *ifa;
 			struct in_device *in_dev = __in_dev_get_rtnl(dev);
@@ -1021,7 +1022,7 @@ no_promotions:
 			 * First of all, we scan fib_info list searching
 			 * for stray nexthop entries, then ignite fib_flush.
 			 */
-			if (fib_sync_down_addr(dev_net(dev), ifa->ifa_local))
+			if (fib_sync_down_addr(dev, ifa->ifa_local))
 				fib_flush(dev_net(dev));
 		}
 	}
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index 6e9ea69e5f75..770bebed6b28 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -56,6 +56,9 @@ int __fib_lookup(struct net *net, struct flowi4 *flp,
 	};
 	int err;
 
+	/* update flow if oif or iif point to device enslaved to l3mdev */
+	l3mdev_update_flow(net, flowi4_to_flowi(flp));
+
 	err = fib_rules_lookup(net->ipv4.rules_ops, flowi4_to_flowi(flp), 0, &arg);
 #ifdef CONFIG_IP_ROUTE_CLASSID
 	if (arg.rule)
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 8066ccc48a17..388d3e21629b 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1057,6 +1057,7 @@ struct fib_info *fib_create_info(struct fib_config *cfg)
 	fi->fib_priority = cfg->fc_priority;
 	fi->fib_prefsrc = cfg->fc_prefsrc;
 	fi->fib_type = cfg->fc_type;
+	fi->fib_tb_id = cfg->fc_table;
 
 	fi->fib_nhs = nhs;
 	change_nexthops(fi) {
@@ -1337,18 +1338,21 @@ nla_put_failure:
  *   referring to it.
  * - device went down -> we must shutdown all nexthops going via it.
  */
-int fib_sync_down_addr(struct net *net, __be32 local)
+int fib_sync_down_addr(struct net_device *dev, __be32 local)
 {
 	int ret = 0;
 	unsigned int hash = fib_laddr_hashfn(local);
 	struct hlist_head *head = &fib_info_laddrhash[hash];
+	struct net *net = dev_net(dev);
+	int tb_id = l3mdev_fib_table(dev);
 	struct fib_info *fi;
 
 	if (!fib_info_laddrhash || local == 0)
 		return 0;
 
 	hlist_for_each_entry(fi, head, fib_lhash) {
-		if (!net_eq(fi->fib_net, net))
+		if (!net_eq(fi->fib_net, net) ||
+		    fi->fib_tb_id != tb_id)
 			continue;
 		if (fi->fib_prefsrc == local) {
 			fi->fib_flags |= RTNH_F_DEAD;
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index e2ffc2a5c7db..241f27bbd7ad 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1081,7 +1081,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 	struct trie *t = (struct trie *)tb->tb_data;
 	struct fib_alias *fa, *new_fa;
 	struct key_vector *l, *tp;
-	unsigned int nlflags = 0;
+	u16 nlflags = NLM_F_EXCL;
 	struct fib_info *fi;
 	u8 plen = cfg->fc_dst_len;
 	u8 slen = KEYLENGTH - plen;
@@ -1126,6 +1126,8 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 		if (cfg->fc_nlflags & NLM_F_EXCL)
 			goto out;
 
+		nlflags &= ~NLM_F_EXCL;
+
 		/* We have 2 goals:
 		 * 1. Find exact match for type, scope, fib_info to avoid
 		 * duplicate routes
@@ -1151,6 +1153,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 			struct fib_info *fi_drop;
 			u8 state;
 
+			nlflags |= NLM_F_REPLACE;
 			fa = fa_first;
 			if (fa_match) {
 				if (fa == fa_match)
@@ -1191,7 +1194,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 			if (state & FA_S_ACCESSED)
 				rt_cache_flush(cfg->fc_nlinfo.nl_net);
 			rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen,
-				tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE);
+				tb->tb_id, &cfg->fc_nlinfo, nlflags);
 
 			goto succeeded;
 		}
@@ -1203,7 +1206,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 			goto out;
 
 		if (cfg->fc_nlflags & NLM_F_APPEND)
-			nlflags = NLM_F_APPEND;
+			nlflags |= NLM_F_APPEND;
 		else
 			fa = fa_first;
 	}
@@ -1211,6 +1214,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
 	if (!(cfg->fc_nlflags & NLM_F_CREATE))
 		goto out;
 
+	nlflags |= NLM_F_CREATE;
 	err = -ENOBUFS;
 	new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL);
 	if (!new_fa)
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index ecd1e09dbbf1..96e0efecefa6 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -24,7 +24,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
 	__be16 protocol = skb->protocol;
 	u16 mac_len = skb->mac_len;
 	int gre_offset, outer_hlen;
-	bool need_csum, ufo;
+	bool need_csum, ufo, gso_partial;
 
 	if (!skb->encapsulation)
 		goto out;
@@ -69,6 +69,8 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
 		goto out;
 	}
 
+	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
+
 	outer_hlen = skb_tnl_header_len(skb);
 	gre_offset = outer_hlen - tnl_hlen;
 	skb = segs;
@@ -96,7 +98,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
 		greh = (struct gre_base_hdr *)skb_transport_header(skb);
 		pcsum = (__sum16 *)(greh + 1);
 
-		if (skb_is_gso(skb)) {
+		if (gso_partial) {
 			unsigned int partial_adj;
 
 			/* Adjust checksum to account for the fact that
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index abfbe492ebfe..e4d16fc5bbb3 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -99,6 +99,7 @@ static size_t inet_sk_attr_size(void)
 		+ nla_total_size(1) /* INET_DIAG_SHUTDOWN */
 		+ nla_total_size(1) /* INET_DIAG_TOS */
 		+ nla_total_size(1) /* INET_DIAG_TCLASS */
+		+ nla_total_size(4) /* INET_DIAG_MARK */
 		+ nla_total_size(sizeof(struct inet_diag_meminfo))
 		+ nla_total_size(sizeof(struct inet_diag_msg))
 		+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
@@ -109,7 +110,8 @@ static size_t inet_sk_attr_size(void)
 
 int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
 			     struct inet_diag_msg *r, int ext,
-			     struct user_namespace *user_ns)
+			     struct user_namespace *user_ns,
+			     bool net_admin)
 {
 	const struct inet_sock *inet = inet_sk(sk);
 
@@ -136,6 +138,9 @@ int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
 	}
 #endif
 
+	if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, sk->sk_mark))
+		goto errout;
+
 	r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
 	r->idiag_inode = sock_i_ino(sk);
 
@@ -149,7 +154,8 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 		      struct sk_buff *skb, const struct inet_diag_req_v2 *req,
 		      struct user_namespace *user_ns,
 		      u32 portid, u32 seq, u16 nlmsg_flags,
-		      const struct nlmsghdr *unlh)
+		      const struct nlmsghdr *unlh,
+		      bool net_admin)
 {
 	const struct tcp_congestion_ops *ca_ops;
 	const struct inet_diag_handler *handler;
@@ -175,7 +181,7 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 	r->idiag_timer = 0;
 	r->idiag_retrans = 0;
 
-	if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns))
+	if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin))
 		goto errout;
 
 	if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
@@ -274,10 +280,11 @@ static int inet_csk_diag_fill(struct sock *sk,
 			      const struct inet_diag_req_v2 *req,
 			      struct user_namespace *user_ns,
 			      u32 portid, u32 seq, u16 nlmsg_flags,
-			      const struct nlmsghdr *unlh)
+			      const struct nlmsghdr *unlh,
+			      bool net_admin)
 {
-	return inet_sk_diag_fill(sk, inet_csk(sk), skb, req,
-				 user_ns, portid, seq, nlmsg_flags, unlh);
+	return inet_sk_diag_fill(sk, inet_csk(sk), skb, req, user_ns,
+				 portid, seq, nlmsg_flags, unlh, net_admin);
 }
 
 static int inet_twsk_diag_fill(struct sock *sk,
@@ -319,8 +326,9 @@ static int inet_twsk_diag_fill(struct sock *sk,
 
 static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
 			      u32 portid, u32 seq, u16 nlmsg_flags,
-			      const struct nlmsghdr *unlh)
+			      const struct nlmsghdr *unlh, bool net_admin)
 {
+	struct request_sock *reqsk = inet_reqsk(sk);
 	struct inet_diag_msg *r;
 	struct nlmsghdr *nlh;
 	long tmo;
@@ -334,7 +342,7 @@ static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
 	inet_diag_msg_common_fill(r, sk);
 	r->idiag_state = TCP_SYN_RECV;
 	r->idiag_timer = 1;
-	r->idiag_retrans = inet_reqsk(sk)->num_retrans;
+	r->idiag_retrans = reqsk->num_retrans;
 
 	BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
 		     offsetof(struct sock, sk_cookie));
@@ -346,6 +354,10 @@ static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
 	r->idiag_uid	= 0;
 	r->idiag_inode	= 0;
 
+	if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
+				     inet_rsk(reqsk)->ir_mark))
+		return -EMSGSIZE;
+
 	nlmsg_end(skb, nlh);
 	return 0;
 }
@@ -354,7 +366,7 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
 			const struct inet_diag_req_v2 *r,
 			struct user_namespace *user_ns,
 			u32 portid, u32 seq, u16 nlmsg_flags,
-			const struct nlmsghdr *unlh)
+			const struct nlmsghdr *unlh, bool net_admin)
 {
 	if (sk->sk_state == TCP_TIME_WAIT)
 		return inet_twsk_diag_fill(sk, skb, portid, seq,
@@ -362,10 +374,10 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
 
 	if (sk->sk_state == TCP_NEW_SYN_RECV)
 		return inet_req_diag_fill(sk, skb, portid, seq,
-					  nlmsg_flags, unlh);
+					  nlmsg_flags, unlh, net_admin);
 
 	return inet_csk_diag_fill(sk, skb, r, user_ns, portid, seq,
-				  nlmsg_flags, unlh);
+				  nlmsg_flags, unlh, net_admin);
 }
 
 struct sock *inet_diag_find_one_icsk(struct net *net,
@@ -435,7 +447,8 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
 	err = sk_diag_fill(sk, rep, req,
 			   sk_user_ns(NETLINK_CB(in_skb).sk),
 			   NETLINK_CB(in_skb).portid,
-			   nlh->nlmsg_seq, 0, nlh);
+			   nlh->nlmsg_seq, 0, nlh,
+			   netlink_net_capable(in_skb, CAP_NET_ADMIN));
 	if (err < 0) {
 		WARN_ON(err == -EMSGSIZE);
 		nlmsg_free(rep);
@@ -796,7 +809,8 @@ static int inet_csk_diag_dump(struct sock *sk,
 			      struct sk_buff *skb,
 			      struct netlink_callback *cb,
 			      const struct inet_diag_req_v2 *r,
-			      const struct nlattr *bc)
+			      const struct nlattr *bc,
+			      bool net_admin)
 {
 	if (!inet_diag_bc_sk(bc, sk))
 		return 0;
@@ -804,7 +818,8 @@ static int inet_csk_diag_dump(struct sock *sk,
 	return inet_csk_diag_fill(sk, skb, r,
 				  sk_user_ns(NETLINK_CB(cb->skb).sk),
 				  NETLINK_CB(cb->skb).portid,
-				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
+				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh,
+				  net_admin);
 }
 
 static void twsk_build_assert(void)
@@ -840,6 +855,7 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
 	struct net *net = sock_net(skb->sk);
 	int i, num, s_i, s_num;
 	u32 idiag_states = r->idiag_states;
+	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 
 	if (idiag_states & TCPF_SYN_RECV)
 		idiag_states |= TCPF_NEW_SYN_RECV;
@@ -880,7 +896,8 @@ void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
 				    cb->args[3] > 0)
 					goto next_listen;
 
-				if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
+				if (inet_csk_diag_dump(sk, skb, cb, r,
+						       bc, net_admin) < 0) {
 					spin_unlock_bh(&ilb->lock);
 					goto done;
 				}
@@ -948,7 +965,7 @@ skip_listen_ht:
 					   sk_user_ns(NETLINK_CB(cb->skb).sk),
 					   NETLINK_CB(cb->skb).portid,
 					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
-					   cb->nlh);
+					   cb->nlh, net_admin);
 			if (res < 0) {
 				spin_unlock_bh(lock);
 				goto done;
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 113cc43df789..576f705d8180 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -246,25 +246,6 @@ static void gre_err(struct sk_buff *skb, u32 info)
 	ipgre_err(skb, info, &tpi);
 }
 
-static __be64 key_to_tunnel_id(__be32 key)
-{
-#ifdef __BIG_ENDIAN
-	return (__force __be64)((__force u32)key);
-#else
-	return (__force __be64)((__force u64)key << 32);
-#endif
-}
-
-/* Returns the least-significant 32 bits of a __be64. */
-static __be32 tunnel_id_to_key(__be64 x)
-{
-#ifdef __BIG_ENDIAN
-	return (__force __be32)x;
-#else
-	return (__force __be32)((__force u64)x >> 32);
-#endif
-}
-
 static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 		       struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
 {
@@ -290,7 +271,7 @@ static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
 			__be64 tun_id;
 
 			flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY);
-			tun_id = key_to_tunnel_id(tpi->key);
+			tun_id = key32_to_tunnel_id(tpi->key);
 			tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0);
 			if (!tun_dst)
 				return PACKET_REJECT;
@@ -446,7 +427,7 @@ static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
 
 	flags = tun_info->key.tun_flags & (TUNNEL_CSUM | TUNNEL_KEY);
 	gre_build_header(skb, tunnel_hlen, flags, proto,
-			 tunnel_id_to_key(tun_info->key.tun_id), 0);
+			 tunnel_id_to_key32(tun_info->key.tun_id), 0);
 
 	df = key->tun_flags & TUNNEL_DONT_FRAGMENT ?  htons(IP_DF) : 0;
 
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 4b351af3e67b..d6feabb03516 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -312,6 +312,7 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
 	const struct iphdr *iph = ip_hdr(skb);
 	struct rtable *rt;
+	struct net_device *dev = skb->dev;
 
 	/* if ingress device is enslaved to an L3 master device pass the
 	 * skb to its handler for processing
@@ -341,7 +342,7 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 	 */
 	if (!skb_valid_dst(skb)) {
 		int err = ip_route_input_noref(skb, iph->daddr, iph->saddr,
-					       iph->tos, skb->dev);
+					       iph->tos, dev);
 		if (unlikely(err)) {
 			if (err == -EXDEV)
 				__NET_INC_STATS(net, LINUX_MIB_IPRPFILTER);
@@ -370,7 +371,7 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 		__IP_UPD_PO_STATS(net, IPSTATS_MIB_INBCAST, skb->len);
 	} else if (skb->pkt_type == PACKET_BROADCAST ||
 		   skb->pkt_type == PACKET_MULTICAST) {
-		struct in_device *in_dev = __in_dev_get_rcu(skb->dev);
+		struct in_device *in_dev = __in_dev_get_rcu(dev);
 
 		/* RFC 1122 3.3.6:
 		 *
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 65569274efb8..05d105832bdb 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -99,6 +99,14 @@ int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb)
 
 	iph->tot_len = htons(skb->len);
 	ip_send_check(iph);
+
+	/* if egress device is enslaved to an L3 master device pass the
+	 * skb to its handler for processing
+	 */
+	skb = l3mdev_ip_out(sk, skb);
+	if (unlikely(!skb))
+		return 0;
+
 	return nf_hook(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
 		       net, sk, skb, NULL, skb_dst(skb)->dev,
 		       dst_output);
@@ -490,7 +498,7 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from)
 	to->tc_index = from->tc_index;
 #endif
 	nf_copy(to, from);
-#if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
+#if IS_ENABLED(CONFIG_IP_VS)
 	to->ipvs_property = from->ipvs_property;
 #endif
 	skb_copy_secmark(to, from);
@@ -1574,8 +1582,7 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb,
 	}
 
 	oif = arg->bound_dev_if;
-	if (!oif && netif_index_is_l3_master(net, skb->skb_iif))
-		oif = skb->skb_iif;
+	oif = oif ? : skb->skb_iif;
 
 	flowi4_init_output(&fl4, oif,
 			   IP4_REPLY_MARK(net, skb->mark),
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 71a52f4d4cff..af4919792b6a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -284,9 +284,12 @@ int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
 			ipc->ttl = val;
 			break;
 		case IP_TOS:
-			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
+			if (cmsg->cmsg_len == CMSG_LEN(sizeof(int)))
+				val = *(int *)CMSG_DATA(cmsg);
+			else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8)))
+				val = *(u8 *)CMSG_DATA(cmsg);
+			else
 				return -EINVAL;
-			val = *(int *)CMSG_DATA(cmsg);
 			if (val < 0 || val > 255)
 				return -EINVAL;
 			ipc->tos = val;
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index 95649ebd2874..5719d6ba0824 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -55,6 +55,7 @@
 #include <net/netns/generic.h>
 #include <net/rtnetlink.h>
 #include <net/udp.h>
+#include <net/dst_metadata.h>
 
 #if IS_ENABLED(CONFIG_IPV6)
 #include <net/ipv6.h>
@@ -546,6 +547,81 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
 	return 0;
 }
 
+void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
+{
+	struct ip_tunnel *tunnel = netdev_priv(dev);
+	u32 headroom = sizeof(struct iphdr);
+	struct ip_tunnel_info *tun_info;
+	const struct ip_tunnel_key *key;
+	const struct iphdr *inner_iph;
+	struct rtable *rt;
+	struct flowi4 fl4;
+	__be16 df = 0;
+	u8 tos, ttl;
+
+	tun_info = skb_tunnel_info(skb);
+	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
+		     ip_tunnel_info_af(tun_info) != AF_INET))
+		goto tx_error;
+	key = &tun_info->key;
+	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
+	inner_iph = (const struct iphdr *)skb_inner_network_header(skb);
+	tos = key->tos;
+	if (tos == 1) {
+		if (skb->protocol == htons(ETH_P_IP))
+			tos = inner_iph->tos;
+		else if (skb->protocol == htons(ETH_P_IPV6))
+			tos = ipv6_get_dsfield((const struct ipv6hdr *)inner_iph);
+	}
+	init_tunnel_flow(&fl4, proto, key->u.ipv4.dst, key->u.ipv4.src, 0,
+			 RT_TOS(tos), tunnel->parms.link);
+	if (tunnel->encap.type != TUNNEL_ENCAP_NONE)
+		goto tx_error;
+	rt = ip_route_output_key(tunnel->net, &fl4);
+	if (IS_ERR(rt)) {
+		dev->stats.tx_carrier_errors++;
+		goto tx_error;
+	}
+	if (rt->dst.dev == dev) {
+		ip_rt_put(rt);
+		dev->stats.collisions++;
+		goto tx_error;
+	}
+	tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
+	ttl = key->ttl;
+	if (ttl == 0) {
+		if (skb->protocol == htons(ETH_P_IP))
+			ttl = inner_iph->ttl;
+		else if (skb->protocol == htons(ETH_P_IPV6))
+			ttl = ((const struct ipv6hdr *)inner_iph)->hop_limit;
+		else
+			ttl = ip4_dst_hoplimit(&rt->dst);
+	}
+	if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
+		df = htons(IP_DF);
+	else if (skb->protocol == htons(ETH_P_IP))
+		df = inner_iph->frag_off & htons(IP_DF);
+	headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
+	if (headroom > dev->needed_headroom)
+		dev->needed_headroom = headroom;
+
+	if (skb_cow_head(skb, dev->needed_headroom)) {
+		ip_rt_put(rt);
+		goto tx_dropped;
+	}
+	iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, proto, key->tos,
+		      key->ttl, df, !net_eq(tunnel->net, dev_net(dev)));
+	return;
+tx_error:
+	dev->stats.tx_errors++;
+	goto kfree;
+tx_dropped:
+	dev->stats.tx_dropped++;
+kfree:
+	kfree_skb(skb);
+}
+EXPORT_SYMBOL_GPL(ip_md_tunnel_xmit);
+
 void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
 		    const struct iphdr *tnl_params, u8 protocol)
 {
diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c
index 0f227db0e9ac..777bc1883870 100644
--- a/net/ipv4/ip_tunnel_core.c
+++ b/net/ipv4/ip_tunnel_core.c
@@ -69,7 +69,7 @@ void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb,
 
 	skb_scrub_packet(skb, xnet);
 
-	skb_clear_hash(skb);
+	skb_clear_hash_if_not_l4(skb);
 	skb_dst_set(skb, &rt->dst);
 	memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index cc701fa70b12..5d7944f394d9 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -88,6 +88,7 @@ static int vti_rcv_cb(struct sk_buff *skb, int err)
 	struct net_device *dev;
 	struct pcpu_sw_netstats *tstats;
 	struct xfrm_state *x;
+	struct xfrm_mode *inner_mode;
 	struct ip_tunnel *tunnel = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4;
 	u32 orig_mark = skb->mark;
 	int ret;
@@ -105,7 +106,19 @@ static int vti_rcv_cb(struct sk_buff *skb, int err)
 	}
 
 	x = xfrm_input_state(skb);
-	family = x->inner_mode->afinfo->family;
+
+	inner_mode = x->inner_mode;
+
+	if (x->sel.family == AF_UNSPEC) {
+		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
+		if (inner_mode == NULL) {
+			XFRM_INC_STATS(dev_net(skb->dev),
+				       LINUX_MIB_XFRMINSTATEMODEERROR);
+			return -EINVAL;
+		}
+	}
+
+	family = inner_mode->afinfo->family;
 
 	skb->mark = be32_to_cpu(tunnel->parms.i_key);
 	ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 4ae3f8e6c6cc..c9392589c415 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -115,6 +115,7 @@
 #include <net/xfrm.h>
 #include <net/net_namespace.h>
 #include <net/netns/generic.h>
+#include <net/dst_metadata.h>
 
 static bool log_ecn_error = true;
 module_param(log_ecn_error, bool, 0644);
@@ -193,6 +194,7 @@ static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
 {
 	struct net *net = dev_net(skb->dev);
 	struct ip_tunnel_net *itn = net_generic(net, ipip_net_id);
+	struct metadata_dst *tun_dst = NULL;
 	struct ip_tunnel *tunnel;
 	const struct iphdr *iph;
 
@@ -216,7 +218,12 @@ static int ipip_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
 			tpi = &ipip_tpi;
 		if (iptunnel_pull_header(skb, 0, tpi->proto, false))
 			goto drop;
-		return ip_tunnel_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
+		if (tunnel->collect_md) {
+			tun_dst = ip_tun_rx_dst(skb, 0, 0, 0);
+			if (!tun_dst)
+				return 0;
+		}
+		return ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
 	}
 
 	return -1;
@@ -270,7 +277,10 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb,
 
 	skb_set_inner_ipproto(skb, ipproto);
 
-	ip_tunnel_xmit(skb, dev, tiph, ipproto);
+	if (tunnel->collect_md)
+		ip_md_tunnel_xmit(skb, dev, ipproto);
+	else
+		ip_tunnel_xmit(skb, dev, tiph, ipproto);
 	return NETDEV_TX_OK;
 
 tx_error:
@@ -380,13 +390,14 @@ static int ipip_tunnel_validate(struct nlattr *tb[], struct nlattr *data[])
 }
 
 static void ipip_netlink_parms(struct nlattr *data[],
-			       struct ip_tunnel_parm *parms)
+			       struct ip_tunnel_parm *parms, bool *collect_md)
 {
 	memset(parms, 0, sizeof(*parms));
 
 	parms->iph.version = 4;
 	parms->iph.protocol = IPPROTO_IPIP;
 	parms->iph.ihl = 5;
+	*collect_md = false;
 
 	if (!data)
 		return;
@@ -414,6 +425,9 @@ static void ipip_netlink_parms(struct nlattr *data[],
 
 	if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
 		parms->iph.frag_off = htons(IP_DF);
+
+	if (data[IFLA_IPTUN_COLLECT_METADATA])
+		*collect_md = true;
 }
 
 /* This function returns true when ENCAP attributes are present in the nl msg */
@@ -453,18 +467,18 @@ static bool ipip_netlink_encap_parms(struct nlattr *data[],
 static int ipip_newlink(struct net *src_net, struct net_device *dev,
 			struct nlattr *tb[], struct nlattr *data[])
 {
+	struct ip_tunnel *t = netdev_priv(dev);
 	struct ip_tunnel_parm p;
 	struct ip_tunnel_encap ipencap;
 
 	if (ipip_netlink_encap_parms(data, &ipencap)) {
-		struct ip_tunnel *t = netdev_priv(dev);
 		int err = ip_tunnel_encap_setup(t, &ipencap);
 
 		if (err < 0)
 			return err;
 	}
 
-	ipip_netlink_parms(data, &p);
+	ipip_netlink_parms(data, &p, &t->collect_md);
 	return ip_tunnel_newlink(dev, tb, &p);
 }
 
@@ -473,6 +487,7 @@ static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
 {
 	struct ip_tunnel_parm p;
 	struct ip_tunnel_encap ipencap;
+	bool collect_md;
 
 	if (ipip_netlink_encap_parms(data, &ipencap)) {
 		struct ip_tunnel *t = netdev_priv(dev);
@@ -482,7 +497,9 @@ static int ipip_changelink(struct net_device *dev, struct nlattr *tb[],
 			return err;
 	}
 
-	ipip_netlink_parms(data, &p);
+	ipip_netlink_parms(data, &p, &collect_md);
+	if (collect_md)
+		return -EINVAL;
 
 	if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
 	    (!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
@@ -516,6 +533,8 @@ static size_t ipip_get_size(const struct net_device *dev)
 		nla_total_size(2) +
 		/* IFLA_IPTUN_ENCAP_DPORT */
 		nla_total_size(2) +
+		/* IFLA_IPTUN_COLLECT_METADATA */
+		nla_total_size(0) +
 		0;
 }
 
@@ -544,6 +563,9 @@ static int ipip_fill_info(struct sk_buff *skb, const struct net_device *dev)
 			tunnel->encap.flags))
 		goto nla_put_failure;
 
+	if (tunnel->collect_md)
+		if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
+			goto nla_put_failure;
 	return 0;
 
 nla_put_failure:
@@ -562,6 +584,7 @@ static const struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
 	[IFLA_IPTUN_ENCAP_FLAGS]	= { .type = NLA_U16 },
 	[IFLA_IPTUN_ENCAP_SPORT]	= { .type = NLA_U16 },
 	[IFLA_IPTUN_ENCAP_DPORT]	= { .type = NLA_U16 },
+	[IFLA_IPTUN_COLLECT_METADATA]	= { .type = NLA_FLAG },
 };
 
 static struct rtnl_link_ops ipip_link_ops __read_mostly = {
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 26253328d227..a87bcd2d4a94 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -2076,6 +2076,7 @@ static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 	struct rta_mfc_stats mfcs;
 	struct nlattr *mp_attr;
 	struct rtnexthop *nhp;
+	unsigned long lastuse;
 	int ct;
 
 	/* If cache is unresolved, don't try to parse IIF and OIF */
@@ -2105,12 +2106,14 @@ static int __ipmr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
 
 	nla_nest_end(skb, mp_attr);
 
+	lastuse = READ_ONCE(c->mfc_un.res.lastuse);
+	lastuse = time_after_eq(jiffies, lastuse) ? jiffies - lastuse : 0;
+
 	mfcs.mfcs_packets = c->mfc_un.res.pkt;
 	mfcs.mfcs_bytes = c->mfc_un.res.bytes;
 	mfcs.mfcs_wrong_if = c->mfc_un.res.wrong_if;
 	if (nla_put_64bit(skb, RTA_MFC_STATS, sizeof(mfcs), &mfcs, RTA_PAD) ||
-	    nla_put_u64_64bit(skb, RTA_EXPIRES,
-			      jiffies_to_clock_t(c->mfc_un.res.lastuse),
+	    nla_put_u64_64bit(skb, RTA_EXPIRES, jiffies_to_clock_t(lastuse),
 			      RTA_PAD))
 		return -EMSGSIZE;
 
diff --git a/net/ipv4/netfilter/nft_chain_route_ipv4.c b/net/ipv4/netfilter/nft_chain_route_ipv4.c
index 2375b0a8be46..30493beb611a 100644
--- a/net/ipv4/netfilter/nft_chain_route_ipv4.c
+++ b/net/ipv4/netfilter/nft_chain_route_ipv4.c
@@ -31,6 +31,7 @@ static unsigned int nf_route_table_hook(void *priv,
 	__be32 saddr, daddr;
 	u_int8_t tos;
 	const struct iphdr *iph;
+	int err;
 
 	/* root is playing with raw sockets. */
 	if (skb->len < sizeof(struct iphdr) ||
@@ -46,15 +47,17 @@ static unsigned int nf_route_table_hook(void *priv,
 	tos = iph->tos;
 
 	ret = nft_do_chain(&pkt, priv);
-	if (ret != NF_DROP && ret != NF_QUEUE) {
+	if (ret != NF_DROP && ret != NF_STOLEN) {
 		iph = ip_hdr(skb);
 
 		if (iph->saddr != saddr ||
 		    iph->daddr != daddr ||
 		    skb->mark != mark ||
-		    iph->tos != tos)
-			if (ip_route_me_harder(state->net, skb, RTN_UNSPEC))
-				ret = NF_DROP;
+		    iph->tos != tos) {
+			err = ip_route_me_harder(state->net, skb, RTN_UNSPEC);
+			if (err < 0)
+				ret = NF_DROP_ERR(err);
+		}
 	}
 	return ret;
 }
diff --git a/net/ipv4/netfilter/nft_reject_ipv4.c b/net/ipv4/netfilter/nft_reject_ipv4.c
index c24f41c816b3..2c2553b9026c 100644
--- a/net/ipv4/netfilter/nft_reject_ipv4.c
+++ b/net/ipv4/netfilter/nft_reject_ipv4.c
@@ -46,6 +46,7 @@ static const struct nft_expr_ops nft_reject_ipv4_ops = {
 	.eval		= nft_reject_ipv4_eval,
 	.init		= nft_reject_init,
 	.dump		= nft_reject_dump,
+	.validate	= nft_reject_validate,
 };
 
 static struct nft_expr_type nft_reject_ipv4_type __read_mostly = {
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 438f50c1a676..90a85c955872 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -606,12 +606,6 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 			    (inet->hdrincl ? FLOWI_FLAG_KNOWN_NH : 0),
 			   daddr, saddr, 0, 0);
 
-	if (!saddr && ipc.oif) {
-		err = l3mdev_get_saddr(net, ipc.oif, &fl4);
-		if (err < 0)
-			goto done;
-	}
-
 	if (!inet->hdrincl) {
 		rfv.msg = msg;
 		rfv.hlen = 0;
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 3e992783c1d0..654a9af20136 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -476,12 +476,18 @@ u32 ip_idents_reserve(u32 hash, int segs)
 	atomic_t *p_id = ip_idents + hash % IP_IDENTS_SZ;
 	u32 old = ACCESS_ONCE(*p_tstamp);
 	u32 now = (u32)jiffies;
-	u32 delta = 0;
+	u32 new, delta = 0;
 
 	if (old != now && cmpxchg(p_tstamp, old, now) == old)
 		delta = prandom_u32_max(now - old);
 
-	return atomic_add_return(segs + delta, p_id) - segs;
+	/* Do not use atomic_add_return() as it makes UBSAN unhappy */
+	do {
+		old = (u32)atomic_read(p_id);
+		new = old + delta + segs;
+	} while (atomic_cmpxchg(p_id, old, new) != old);
+
+	return new - segs;
 }
 EXPORT_SYMBOL(ip_idents_reserve);
 
@@ -1831,7 +1837,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	 *	Now we are ready to route packet.
 	 */
 	fl4.flowi4_oif = 0;
-	fl4.flowi4_iif = l3mdev_fib_oif_rcu(dev);
+	fl4.flowi4_iif = dev->ifindex;
 	fl4.flowi4_mark = skb->mark;
 	fl4.flowi4_tos = tos;
 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
@@ -2018,7 +2024,9 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 		return ERR_PTR(-EINVAL);
 
 	if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
-		if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
+		if (ipv4_is_loopback(fl4->saddr) &&
+		    !(dev_out->flags & IFF_LOOPBACK) &&
+		    !netif_is_l3_master(dev_out))
 			return ERR_PTR(-EINVAL);
 
 	if (ipv4_is_lbcast(fl4->daddr))
@@ -2148,7 +2156,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 	unsigned int flags = 0;
 	struct fib_result res;
 	struct rtable *rth;
-	int master_idx;
 	int orig_oif;
 	int err = -ENETUNREACH;
 
@@ -2158,9 +2165,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 
 	orig_oif = fl4->flowi4_oif;
 
-	master_idx = l3mdev_master_ifindex_by_index(net, fl4->flowi4_oif);
-	if (master_idx)
-		fl4->flowi4_oif = master_idx;
 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
 	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
@@ -2244,10 +2248,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 				fl4->saddr = inet_select_addr(dev_out, 0,
 							      RT_SCOPE_HOST);
 		}
-
-		rth = l3mdev_get_rtable(dev_out, fl4);
-		if (rth)
-			goto out;
 	}
 
 	if (!fl4->daddr) {
@@ -2265,8 +2265,7 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 	if (err) {
 		res.fi = NULL;
 		res.table = NULL;
-		if (fl4->flowi4_oif &&
-		    !netif_index_is_l3_master(net, fl4->flowi4_oif)) {
+		if (fl4->flowi4_oif) {
 			/* Apparently, routing tables are wrong. Assume,
 			   that the destination is on link.
 
@@ -2302,7 +2301,9 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 			else
 				fl4->saddr = fl4->daddr;
 		}
-		dev_out = net->loopback_dev;
+
+		/* L3 master device is the loopback for that domain */
+		dev_out = l3mdev_master_dev_rcu(dev_out) ? : net->loopback_dev;
 		fl4->flowi4_oif = dev_out->ifindex;
 		flags |= RTCF_LOCAL;
 		goto make_route;
@@ -2577,9 +2578,6 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 	fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
 	fl4.flowi4_mark = mark;
 
-	if (netif_index_is_l3_master(net, fl4.flowi4_oif))
-		fl4.flowi4_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF;
-
 	if (iif) {
 		struct net_device *dev;
 
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 77311a92275c..f253e5019d22 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -380,14 +380,14 @@ void tcp_init_sock(struct sock *sk)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 
-	__skb_queue_head_init(&tp->out_of_order_queue);
+	tp->out_of_order_queue = RB_ROOT;
 	tcp_init_xmit_timers(sk);
 	tcp_prequeue_init(tp);
 	INIT_LIST_HEAD(&tp->tsq_node);
 
 	icsk->icsk_rto = TCP_TIMEOUT_INIT;
 	tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT);
-	tp->rtt_min[0].rtt = ~0U;
+	minmax_reset(&tp->rtt_min, tcp_time_stamp, ~0U);
 
 	/* So many TCP implementations out there (incorrectly) count the
 	 * initial SYN frame in their delayed-ACK and congestion control
@@ -396,6 +396,9 @@ void tcp_init_sock(struct sock *sk)
 	 */
 	tp->snd_cwnd = TCP_INIT_CWND;
 
+	/* There's a bubble in the pipe until at least the first ACK. */
+	tp->app_limited = ~0U;
+
 	/* See draft-stevens-tcpca-spec-01 for discussion of the
 	 * initialization of these values.
 	 */
@@ -1014,23 +1017,40 @@ int tcp_sendpage(struct sock *sk, struct page *page, int offset,
 					flags);
 
 	lock_sock(sk);
+
+	tcp_rate_check_app_limited(sk);  /* is sending application-limited? */
+
 	res = do_tcp_sendpages(sk, page, offset, size, flags);
 	release_sock(sk);
 	return res;
 }
 EXPORT_SYMBOL(tcp_sendpage);
 
-static inline int select_size(const struct sock *sk, bool sg)
+/* Do not bother using a page frag for very small frames.
+ * But use this heuristic only for the first skb in write queue.
+ *
+ * Having no payload in skb->head allows better SACK shifting
+ * in tcp_shift_skb_data(), reducing sack/rack overhead, because
+ * write queue has less skbs.
+ * Each skb can hold up to MAX_SKB_FRAGS * 32Kbytes, or ~0.5 MB.
+ * This also speeds up tso_fragment(), since it wont fallback
+ * to tcp_fragment().
+ */
+static int linear_payload_sz(bool first_skb)
+{
+	if (first_skb)
+		return SKB_WITH_OVERHEAD(2048 - MAX_TCP_HEADER);
+	return 0;
+}
+
+static int select_size(const struct sock *sk, bool sg, bool first_skb)
 {
 	const struct tcp_sock *tp = tcp_sk(sk);
 	int tmp = tp->mss_cache;
 
 	if (sg) {
 		if (sk_can_gso(sk)) {
-			/* Small frames wont use a full page:
-			 * Payload will immediately follow tcp header.
-			 */
-			tmp = SKB_WITH_OVERHEAD(2048 - MAX_TCP_HEADER);
+			tmp = linear_payload_sz(first_skb);
 		} else {
 			int pgbreak = SKB_MAX_HEAD(MAX_TCP_HEADER);
 
@@ -1101,6 +1121,8 @@ int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 
 	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 
+	tcp_rate_check_app_limited(sk);  /* is sending application-limited? */
+
 	/* Wait for a connection to finish. One exception is TCP Fast Open
 	 * (passive side) where data is allowed to be sent before a connection
 	 * is fully established.
@@ -1161,6 +1183,8 @@ restart:
 		}
 
 		if (copy <= 0 || !tcp_skb_can_collapse_to(skb)) {
+			bool first_skb;
+
 new_segment:
 			/* Allocate new segment. If the interface is SG,
 			 * allocate skb fitting to single page.
@@ -1172,10 +1196,11 @@ new_segment:
 				process_backlog = false;
 				goto restart;
 			}
+			first_skb = skb_queue_empty(&sk->sk_write_queue);
 			skb = sk_stream_alloc_skb(sk,
-						  select_size(sk, sg),
+						  select_size(sk, sg, first_skb),
 						  sk->sk_allocation,
-						  skb_queue_empty(&sk->sk_write_queue));
+						  first_skb);
 			if (!skb)
 				goto wait_for_memory;
 
@@ -2243,7 +2268,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 	tcp_clear_xmit_timers(sk);
 	__skb_queue_purge(&sk->sk_receive_queue);
 	tcp_write_queue_purge(sk);
-	__skb_queue_purge(&tp->out_of_order_queue);
+	skb_rbtree_purge(&tp->out_of_order_queue);
 
 	inet->inet_dport = 0;
 
@@ -2687,7 +2712,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 {
 	const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */
 	const struct inet_connection_sock *icsk = inet_csk(sk);
-	u32 now = tcp_time_stamp;
+	u32 now = tcp_time_stamp, intv;
 	unsigned int start;
 	int notsent_bytes;
 	u64 rate64;
@@ -2777,6 +2802,15 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	info->tcpi_min_rtt = tcp_min_rtt(tp);
 	info->tcpi_data_segs_in = tp->data_segs_in;
 	info->tcpi_data_segs_out = tp->data_segs_out;
+
+	info->tcpi_delivery_rate_app_limited = tp->rate_app_limited ? 1 : 0;
+	rate = READ_ONCE(tp->rate_delivered);
+	intv = READ_ONCE(tp->rate_interval_us);
+	if (rate && intv) {
+		rate64 = (u64)rate * tp->mss_cache * USEC_PER_SEC;
+		do_div(rate64, intv);
+		put_unaligned(rate64, &info->tcpi_delivery_rate);
+	}
 }
 EXPORT_SYMBOL_GPL(tcp_get_info);
 
@@ -3244,11 +3278,12 @@ static void __init tcp_init_mem(void)
 
 void __init tcp_init(void)
 {
-	unsigned long limit;
 	int max_rshare, max_wshare, cnt;
+	unsigned long limit;
 	unsigned int i;
 
-	sock_skb_cb_check_size(sizeof(struct tcp_skb_cb));
+	BUILD_BUG_ON(sizeof(struct tcp_skb_cb) >
+		     FIELD_SIZEOF(struct sk_buff, cb));
 
 	percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
 	percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
new file mode 100644
index 000000000000..0ea66c2c9344
--- /dev/null
+++ b/net/ipv4/tcp_bbr.c
@@ -0,0 +1,896 @@
+/* Bottleneck Bandwidth and RTT (BBR) congestion control
+ *
+ * BBR congestion control computes the sending rate based on the delivery
+ * rate (throughput) estimated from ACKs. In a nutshell:
+ *
+ *   On each ACK, update our model of the network path:
+ *      bottleneck_bandwidth = windowed_max(delivered / elapsed, 10 round trips)
+ *      min_rtt = windowed_min(rtt, 10 seconds)
+ *   pacing_rate = pacing_gain * bottleneck_bandwidth
+ *   cwnd = max(cwnd_gain * bottleneck_bandwidth * min_rtt, 4)
+ *
+ * The core algorithm does not react directly to packet losses or delays,
+ * although BBR may adjust the size of next send per ACK when loss is
+ * observed, or adjust the sending rate if it estimates there is a
+ * traffic policer, in order to keep the drop rate reasonable.
+ *
+ * BBR is described in detail in:
+ *   "BBR: Congestion-Based Congestion Control",
+ *   Neal Cardwell, Yuchung Cheng, C. Stephen Gunn, Soheil Hassas Yeganeh,
+ *   Van Jacobson. ACM Queue, Vol. 14 No. 5, September-October 2016.
+ *
+ * There is a public e-mail list for discussing BBR development and testing:
+ *   https://groups.google.com/forum/#!forum/bbr-dev
+ *
+ * NOTE: BBR *must* be used with the fq qdisc ("man tc-fq") with pacing enabled,
+ * since pacing is integral to the BBR design and implementation.
+ * BBR without pacing would not function properly, and may incur unnecessary
+ * high packet loss rates.
+ */
+#include <linux/module.h>
+#include <net/tcp.h>
+#include <linux/inet_diag.h>
+#include <linux/inet.h>
+#include <linux/random.h>
+#include <linux/win_minmax.h>
+
+/* Scale factor for rate in pkt/uSec unit to avoid truncation in bandwidth
+ * estimation. The rate unit ~= (1500 bytes / 1 usec / 2^24) ~= 715 bps.
+ * This handles bandwidths from 0.06pps (715bps) to 256Mpps (3Tbps) in a u32.
+ * Since the minimum window is >=4 packets, the lower bound isn't
+ * an issue. The upper bound isn't an issue with existing technologies.
+ */
+#define BW_SCALE 24
+#define BW_UNIT (1 << BW_SCALE)
+
+#define BBR_SCALE 8	/* scaling factor for fractions in BBR (e.g. gains) */
+#define BBR_UNIT (1 << BBR_SCALE)
+
+/* BBR has the following modes for deciding how fast to send: */
+enum bbr_mode {
+	BBR_STARTUP,	/* ramp up sending rate rapidly to fill pipe */
+	BBR_DRAIN,	/* drain any queue created during startup */
+	BBR_PROBE_BW,	/* discover, share bw: pace around estimated bw */
+	BBR_PROBE_RTT,	/* cut cwnd to min to probe min_rtt */
+};
+
+/* BBR congestion control block */
+struct bbr {
+	u32	min_rtt_us;	        /* min RTT in min_rtt_win_sec window */
+	u32	min_rtt_stamp;	        /* timestamp of min_rtt_us */
+	u32	probe_rtt_done_stamp;   /* end time for BBR_PROBE_RTT mode */
+	struct minmax bw;	/* Max recent delivery rate in pkts/uS << 24 */
+	u32	rtt_cnt;	    /* count of packet-timed rounds elapsed */
+	u32     next_rtt_delivered; /* scb->tx.delivered at end of round */
+	struct skb_mstamp cycle_mstamp;  /* time of this cycle phase start */
+	u32     mode:3,		     /* current bbr_mode in state machine */
+		prev_ca_state:3,     /* CA state on previous ACK */
+		packet_conservation:1,  /* use packet conservation? */
+		restore_cwnd:1,	     /* decided to revert cwnd to old value */
+		round_start:1,	     /* start of packet-timed tx->ack round? */
+		tso_segs_goal:7,     /* segments we want in each skb we send */
+		idle_restart:1,	     /* restarting after idle? */
+		probe_rtt_round_done:1,  /* a BBR_PROBE_RTT round at 4 pkts? */
+		unused:5,
+		lt_is_sampling:1,    /* taking long-term ("LT") samples now? */
+		lt_rtt_cnt:7,	     /* round trips in long-term interval */
+		lt_use_bw:1;	     /* use lt_bw as our bw estimate? */
+	u32	lt_bw;		     /* LT est delivery rate in pkts/uS << 24 */
+	u32	lt_last_delivered;   /* LT intvl start: tp->delivered */
+	u32	lt_last_stamp;	     /* LT intvl start: tp->delivered_mstamp */
+	u32	lt_last_lost;	     /* LT intvl start: tp->lost */
+	u32	pacing_gain:10,	/* current gain for setting pacing rate */
+		cwnd_gain:10,	/* current gain for setting cwnd */
+		full_bw_cnt:3,	/* number of rounds without large bw gains */
+		cycle_idx:3,	/* current index in pacing_gain cycle array */
+		unused_b:6;
+	u32	prior_cwnd;	/* prior cwnd upon entering loss recovery */
+	u32	full_bw;	/* recent bw, to estimate if pipe is full */
+};
+
+#define CYCLE_LEN	8	/* number of phases in a pacing gain cycle */
+
+/* Window length of bw filter (in rounds): */
+static const int bbr_bw_rtts = CYCLE_LEN + 2;
+/* Window length of min_rtt filter (in sec): */
+static const u32 bbr_min_rtt_win_sec = 10;
+/* Minimum time (in ms) spent at bbr_cwnd_min_target in BBR_PROBE_RTT mode: */
+static const u32 bbr_probe_rtt_mode_ms = 200;
+/* Skip TSO below the following bandwidth (bits/sec): */
+static const int bbr_min_tso_rate = 1200000;
+
+/* We use a high_gain value of 2/ln(2) because it's the smallest pacing gain
+ * that will allow a smoothly increasing pacing rate that will double each RTT
+ * and send the same number of packets per RTT that an un-paced, slow-starting
+ * Reno or CUBIC flow would:
+ */
+static const int bbr_high_gain  = BBR_UNIT * 2885 / 1000 + 1;
+/* The pacing gain of 1/high_gain in BBR_DRAIN is calculated to typically drain
+ * the queue created in BBR_STARTUP in a single round:
+ */
+static const int bbr_drain_gain = BBR_UNIT * 1000 / 2885;
+/* The gain for deriving steady-state cwnd tolerates delayed/stretched ACKs: */
+static const int bbr_cwnd_gain  = BBR_UNIT * 2;
+/* The pacing_gain values for the PROBE_BW gain cycle, to discover/share bw: */
+static const int bbr_pacing_gain[] = {
+	BBR_UNIT * 5 / 4,	/* probe for more available bw */
+	BBR_UNIT * 3 / 4,	/* drain queue and/or yield bw to other flows */
+	BBR_UNIT, BBR_UNIT, BBR_UNIT,	/* cruise at 1.0*bw to utilize pipe, */
+	BBR_UNIT, BBR_UNIT, BBR_UNIT	/* without creating excess queue... */
+};
+/* Randomize the starting gain cycling phase over N phases: */
+static const u32 bbr_cycle_rand = 7;
+
+/* Try to keep at least this many packets in flight, if things go smoothly. For
+ * smooth functioning, a sliding window protocol ACKing every other packet
+ * needs at least 4 packets in flight:
+ */
+static const u32 bbr_cwnd_min_target = 4;
+
+/* To estimate if BBR_STARTUP mode (i.e. high_gain) has filled pipe... */
+/* If bw has increased significantly (1.25x), there may be more bw available: */
+static const u32 bbr_full_bw_thresh = BBR_UNIT * 5 / 4;
+/* But after 3 rounds w/o significant bw growth, estimate pipe is full: */
+static const u32 bbr_full_bw_cnt = 3;
+
+/* "long-term" ("LT") bandwidth estimator parameters... */
+/* The minimum number of rounds in an LT bw sampling interval: */
+static const u32 bbr_lt_intvl_min_rtts = 4;
+/* If lost/delivered ratio > 20%, interval is "lossy" and we may be policed: */
+static const u32 bbr_lt_loss_thresh = 50;
+/* If 2 intervals have a bw ratio <= 1/8, their bw is "consistent": */
+static const u32 bbr_lt_bw_ratio = BBR_UNIT / 8;
+/* If 2 intervals have a bw diff <= 4 Kbit/sec their bw is "consistent": */
+static const u32 bbr_lt_bw_diff = 4000 / 8;
+/* If we estimate we're policed, use lt_bw for this many round trips: */
+static const u32 bbr_lt_bw_max_rtts = 48;
+
+/* Do we estimate that STARTUP filled the pipe? */
+static bool bbr_full_bw_reached(const struct sock *sk)
+{
+	const struct bbr *bbr = inet_csk_ca(sk);
+
+	return bbr->full_bw_cnt >= bbr_full_bw_cnt;
+}
+
+/* Return the windowed max recent bandwidth sample, in pkts/uS << BW_SCALE. */
+static u32 bbr_max_bw(const struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	return minmax_get(&bbr->bw);
+}
+
+/* Return the estimated bandwidth of the path, in pkts/uS << BW_SCALE. */
+static u32 bbr_bw(const struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	return bbr->lt_use_bw ? bbr->lt_bw : bbr_max_bw(sk);
+}
+
+/* Return rate in bytes per second, optionally with a gain.
+ * The order here is chosen carefully to avoid overflow of u64. This should
+ * work for input rates of up to 2.9Tbit/sec and gain of 2.89x.
+ */
+static u64 bbr_rate_bytes_per_sec(struct sock *sk, u64 rate, int gain)
+{
+	rate *= tcp_mss_to_mtu(sk, tcp_sk(sk)->mss_cache);
+	rate *= gain;
+	rate >>= BBR_SCALE;
+	rate *= USEC_PER_SEC;
+	return rate >> BW_SCALE;
+}
+
+/* Pace using current bw estimate and a gain factor. In order to help drive the
+ * network toward lower queues while maintaining high utilization and low
+ * latency, the average pacing rate aims to be slightly (~1%) lower than the
+ * estimated bandwidth. This is an important aspect of the design. In this
+ * implementation this slightly lower pacing rate is achieved implicitly by not
+ * including link-layer headers in the packet size used for the pacing rate.
+ */
+static void bbr_set_pacing_rate(struct sock *sk, u32 bw, int gain)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+	u64 rate = bw;
+
+	rate = bbr_rate_bytes_per_sec(sk, rate, gain);
+	rate = min_t(u64, rate, sk->sk_max_pacing_rate);
+	if (bbr->mode != BBR_STARTUP || rate > sk->sk_pacing_rate)
+		sk->sk_pacing_rate = rate;
+}
+
+/* Return count of segments we want in the skbs we send, or 0 for default. */
+static u32 bbr_tso_segs_goal(struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	return bbr->tso_segs_goal;
+}
+
+static void bbr_set_tso_segs_goal(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 min_segs;
+
+	min_segs = sk->sk_pacing_rate < (bbr_min_tso_rate >> 3) ? 1 : 2;
+	bbr->tso_segs_goal = min(tcp_tso_autosize(sk, tp->mss_cache, min_segs),
+				 0x7FU);
+}
+
+/* Save "last known good" cwnd so we can restore it after losses or PROBE_RTT */
+static void bbr_save_cwnd(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	if (bbr->prev_ca_state < TCP_CA_Recovery && bbr->mode != BBR_PROBE_RTT)
+		bbr->prior_cwnd = tp->snd_cwnd;  /* this cwnd is good enough */
+	else  /* loss recovery or BBR_PROBE_RTT have temporarily cut cwnd */
+		bbr->prior_cwnd = max(bbr->prior_cwnd, tp->snd_cwnd);
+}
+
+static void bbr_cwnd_event(struct sock *sk, enum tcp_ca_event event)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	if (event == CA_EVENT_TX_START && tp->app_limited) {
+		bbr->idle_restart = 1;
+		/* Avoid pointless buffer overflows: pace at est. bw if we don't
+		 * need more speed (we're restarting from idle and app-limited).
+		 */
+		if (bbr->mode == BBR_PROBE_BW)
+			bbr_set_pacing_rate(sk, bbr_bw(sk), BBR_UNIT);
+	}
+}
+
+/* Find target cwnd. Right-size the cwnd based on min RTT and the
+ * estimated bottleneck bandwidth:
+ *
+ * cwnd = bw * min_rtt * gain = BDP * gain
+ *
+ * The key factor, gain, controls the amount of queue. While a small gain
+ * builds a smaller queue, it becomes more vulnerable to noise in RTT
+ * measurements (e.g., delayed ACKs or other ACK compression effects). This
+ * noise may cause BBR to under-estimate the rate.
+ *
+ * To achieve full performance in high-speed paths, we budget enough cwnd to
+ * fit full-sized skbs in-flight on both end hosts to fully utilize the path:
+ *   - one skb in sending host Qdisc,
+ *   - one skb in sending host TSO/GSO engine
+ *   - one skb being received by receiver host LRO/GRO/delayed-ACK engine
+ * Don't worry, at low rates (bbr_min_tso_rate) this won't bloat cwnd because
+ * in such cases tso_segs_goal is 1. The minimum cwnd is 4 packets,
+ * which allows 2 outstanding 2-packet sequences, to try to keep pipe
+ * full even with ACK-every-other-packet delayed ACKs.
+ */
+static u32 bbr_target_cwnd(struct sock *sk, u32 bw, int gain)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 cwnd;
+	u64 w;
+
+	/* If we've never had a valid RTT sample, cap cwnd at the initial
+	 * default. This should only happen when the connection is not using TCP
+	 * timestamps and has retransmitted all of the SYN/SYNACK/data packets
+	 * ACKed so far. In this case, an RTO can cut cwnd to 1, in which
+	 * case we need to slow-start up toward something safe: TCP_INIT_CWND.
+	 */
+	if (unlikely(bbr->min_rtt_us == ~0U))	 /* no valid RTT samples yet? */
+		return TCP_INIT_CWND;  /* be safe: cap at default initial cwnd*/
+
+	w = (u64)bw * bbr->min_rtt_us;
+
+	/* Apply a gain to the given value, then remove the BW_SCALE shift. */
+	cwnd = (((w * gain) >> BBR_SCALE) + BW_UNIT - 1) / BW_UNIT;
+
+	/* Allow enough full-sized skbs in flight to utilize end systems. */
+	cwnd += 3 * bbr->tso_segs_goal;
+
+	/* Reduce delayed ACKs by rounding up cwnd to the next even number. */
+	cwnd = (cwnd + 1) & ~1U;
+
+	return cwnd;
+}
+
+/* An optimization in BBR to reduce losses: On the first round of recovery, we
+ * follow the packet conservation principle: send P packets per P packets acked.
+ * After that, we slow-start and send at most 2*P packets per P packets acked.
+ * After recovery finishes, or upon undo, we restore the cwnd we had when
+ * recovery started (capped by the target cwnd based on estimated BDP).
+ *
+ * TODO(ycheng/ncardwell): implement a rate-based approach.
+ */
+static bool bbr_set_cwnd_to_recover_or_restore(
+	struct sock *sk, const struct rate_sample *rs, u32 acked, u32 *new_cwnd)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u8 prev_state = bbr->prev_ca_state, state = inet_csk(sk)->icsk_ca_state;
+	u32 cwnd = tp->snd_cwnd;
+
+	/* An ACK for P pkts should release at most 2*P packets. We do this
+	 * in two steps. First, here we deduct the number of lost packets.
+	 * Then, in bbr_set_cwnd() we slow start up toward the target cwnd.
+	 */
+	if (rs->losses > 0)
+		cwnd = max_t(s32, cwnd - rs->losses, 1);
+
+	if (state == TCP_CA_Recovery && prev_state != TCP_CA_Recovery) {
+		/* Starting 1st round of Recovery, so do packet conservation. */
+		bbr->packet_conservation = 1;
+		bbr->next_rtt_delivered = tp->delivered;  /* start round now */
+		/* Cut unused cwnd from app behavior, TSQ, or TSO deferral: */
+		cwnd = tcp_packets_in_flight(tp) + acked;
+	} else if (prev_state >= TCP_CA_Recovery && state < TCP_CA_Recovery) {
+		/* Exiting loss recovery; restore cwnd saved before recovery. */
+		bbr->restore_cwnd = 1;
+		bbr->packet_conservation = 0;
+	}
+	bbr->prev_ca_state = state;
+
+	if (bbr->restore_cwnd) {
+		/* Restore cwnd after exiting loss recovery or PROBE_RTT. */
+		cwnd = max(cwnd, bbr->prior_cwnd);
+		bbr->restore_cwnd = 0;
+	}
+
+	if (bbr->packet_conservation) {
+		*new_cwnd = max(cwnd, tcp_packets_in_flight(tp) + acked);
+		return true;	/* yes, using packet conservation */
+	}
+	*new_cwnd = cwnd;
+	return false;
+}
+
+/* Slow-start up toward target cwnd (if bw estimate is growing, or packet loss
+ * has drawn us down below target), or snap down to target if we're above it.
+ */
+static void bbr_set_cwnd(struct sock *sk, const struct rate_sample *rs,
+			 u32 acked, u32 bw, int gain)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 cwnd = 0, target_cwnd = 0;
+
+	if (!acked)
+		return;
+
+	if (bbr_set_cwnd_to_recover_or_restore(sk, rs, acked, &cwnd))
+		goto done;
+
+	/* If we're below target cwnd, slow start cwnd toward target cwnd. */
+	target_cwnd = bbr_target_cwnd(sk, bw, gain);
+	if (bbr_full_bw_reached(sk))  /* only cut cwnd if we filled the pipe */
+		cwnd = min(cwnd + acked, target_cwnd);
+	else if (cwnd < target_cwnd || tp->delivered < TCP_INIT_CWND)
+		cwnd = cwnd + acked;
+	cwnd = max(cwnd, bbr_cwnd_min_target);
+
+done:
+	tp->snd_cwnd = min(cwnd, tp->snd_cwnd_clamp);	/* apply global cap */
+	if (bbr->mode == BBR_PROBE_RTT)  /* drain queue, refresh min_rtt */
+		tp->snd_cwnd = min(tp->snd_cwnd, bbr_cwnd_min_target);
+}
+
+/* End cycle phase if it's time and/or we hit the phase's in-flight target. */
+static bool bbr_is_next_cycle_phase(struct sock *sk,
+				    const struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	bool is_full_length =
+		skb_mstamp_us_delta(&tp->delivered_mstamp, &bbr->cycle_mstamp) >
+		bbr->min_rtt_us;
+	u32 inflight, bw;
+
+	/* The pacing_gain of 1.0 paces at the estimated bw to try to fully
+	 * use the pipe without increasing the queue.
+	 */
+	if (bbr->pacing_gain == BBR_UNIT)
+		return is_full_length;		/* just use wall clock time */
+
+	inflight = rs->prior_in_flight;  /* what was in-flight before ACK? */
+	bw = bbr_max_bw(sk);
+
+	/* A pacing_gain > 1.0 probes for bw by trying to raise inflight to at
+	 * least pacing_gain*BDP; this may take more than min_rtt if min_rtt is
+	 * small (e.g. on a LAN). We do not persist if packets are lost, since
+	 * a path with small buffers may not hold that much.
+	 */
+	if (bbr->pacing_gain > BBR_UNIT)
+		return is_full_length &&
+			(rs->losses ||  /* perhaps pacing_gain*BDP won't fit */
+			 inflight >= bbr_target_cwnd(sk, bw, bbr->pacing_gain));
+
+	/* A pacing_gain < 1.0 tries to drain extra queue we added if bw
+	 * probing didn't find more bw. If inflight falls to match BDP then we
+	 * estimate queue is drained; persisting would underutilize the pipe.
+	 */
+	return is_full_length ||
+		inflight <= bbr_target_cwnd(sk, bw, BBR_UNIT);
+}
+
+static void bbr_advance_cycle_phase(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	bbr->cycle_idx = (bbr->cycle_idx + 1) & (CYCLE_LEN - 1);
+	bbr->cycle_mstamp = tp->delivered_mstamp;
+	bbr->pacing_gain = bbr_pacing_gain[bbr->cycle_idx];
+}
+
+/* Gain cycling: cycle pacing gain to converge to fair share of available bw. */
+static void bbr_update_cycle_phase(struct sock *sk,
+				   const struct rate_sample *rs)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	if ((bbr->mode == BBR_PROBE_BW) && !bbr->lt_use_bw &&
+	    bbr_is_next_cycle_phase(sk, rs))
+		bbr_advance_cycle_phase(sk);
+}
+
+static void bbr_reset_startup_mode(struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	bbr->mode = BBR_STARTUP;
+	bbr->pacing_gain = bbr_high_gain;
+	bbr->cwnd_gain	 = bbr_high_gain;
+}
+
+static void bbr_reset_probe_bw_mode(struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	bbr->mode = BBR_PROBE_BW;
+	bbr->pacing_gain = BBR_UNIT;
+	bbr->cwnd_gain = bbr_cwnd_gain;
+	bbr->cycle_idx = CYCLE_LEN - 1 - prandom_u32_max(bbr_cycle_rand);
+	bbr_advance_cycle_phase(sk);	/* flip to next phase of gain cycle */
+}
+
+static void bbr_reset_mode(struct sock *sk)
+{
+	if (!bbr_full_bw_reached(sk))
+		bbr_reset_startup_mode(sk);
+	else
+		bbr_reset_probe_bw_mode(sk);
+}
+
+/* Start a new long-term sampling interval. */
+static void bbr_reset_lt_bw_sampling_interval(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	bbr->lt_last_stamp = tp->delivered_mstamp.stamp_jiffies;
+	bbr->lt_last_delivered = tp->delivered;
+	bbr->lt_last_lost = tp->lost;
+	bbr->lt_rtt_cnt = 0;
+}
+
+/* Completely reset long-term bandwidth sampling. */
+static void bbr_reset_lt_bw_sampling(struct sock *sk)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	bbr->lt_bw = 0;
+	bbr->lt_use_bw = 0;
+	bbr->lt_is_sampling = false;
+	bbr_reset_lt_bw_sampling_interval(sk);
+}
+
+/* Long-term bw sampling interval is done. Estimate whether we're policed. */
+static void bbr_lt_bw_interval_done(struct sock *sk, u32 bw)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 diff;
+
+	if (bbr->lt_bw) {  /* do we have bw from a previous interval? */
+		/* Is new bw close to the lt_bw from the previous interval? */
+		diff = abs(bw - bbr->lt_bw);
+		if ((diff * BBR_UNIT <= bbr_lt_bw_ratio * bbr->lt_bw) ||
+		    (bbr_rate_bytes_per_sec(sk, diff, BBR_UNIT) <=
+		     bbr_lt_bw_diff)) {
+			/* All criteria are met; estimate we're policed. */
+			bbr->lt_bw = (bw + bbr->lt_bw) >> 1;  /* avg 2 intvls */
+			bbr->lt_use_bw = 1;
+			bbr->pacing_gain = BBR_UNIT;  /* try to avoid drops */
+			bbr->lt_rtt_cnt = 0;
+			return;
+		}
+	}
+	bbr->lt_bw = bw;
+	bbr_reset_lt_bw_sampling_interval(sk);
+}
+
+/* Token-bucket traffic policers are common (see "An Internet-Wide Analysis of
+ * Traffic Policing", SIGCOMM 2016). BBR detects token-bucket policers and
+ * explicitly models their policed rate, to reduce unnecessary losses. We
+ * estimate that we're policed if we see 2 consecutive sampling intervals with
+ * consistent throughput and high packet loss. If we think we're being policed,
+ * set lt_bw to the "long-term" average delivery rate from those 2 intervals.
+ */
+static void bbr_lt_bw_sampling(struct sock *sk, const struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 lost, delivered;
+	u64 bw;
+	s32 t;
+
+	if (bbr->lt_use_bw) {	/* already using long-term rate, lt_bw? */
+		if (bbr->mode == BBR_PROBE_BW && bbr->round_start &&
+		    ++bbr->lt_rtt_cnt >= bbr_lt_bw_max_rtts) {
+			bbr_reset_lt_bw_sampling(sk);    /* stop using lt_bw */
+			bbr_reset_probe_bw_mode(sk);  /* restart gain cycling */
+		}
+		return;
+	}
+
+	/* Wait for the first loss before sampling, to let the policer exhaust
+	 * its tokens and estimate the steady-state rate allowed by the policer.
+	 * Starting samples earlier includes bursts that over-estimate the bw.
+	 */
+	if (!bbr->lt_is_sampling) {
+		if (!rs->losses)
+			return;
+		bbr_reset_lt_bw_sampling_interval(sk);
+		bbr->lt_is_sampling = true;
+	}
+
+	/* To avoid underestimates, reset sampling if we run out of data. */
+	if (rs->is_app_limited) {
+		bbr_reset_lt_bw_sampling(sk);
+		return;
+	}
+
+	if (bbr->round_start)
+		bbr->lt_rtt_cnt++;	/* count round trips in this interval */
+	if (bbr->lt_rtt_cnt < bbr_lt_intvl_min_rtts)
+		return;		/* sampling interval needs to be longer */
+	if (bbr->lt_rtt_cnt > 4 * bbr_lt_intvl_min_rtts) {
+		bbr_reset_lt_bw_sampling(sk);  /* interval is too long */
+		return;
+	}
+
+	/* End sampling interval when a packet is lost, so we estimate the
+	 * policer tokens were exhausted. Stopping the sampling before the
+	 * tokens are exhausted under-estimates the policed rate.
+	 */
+	if (!rs->losses)
+		return;
+
+	/* Calculate packets lost and delivered in sampling interval. */
+	lost = tp->lost - bbr->lt_last_lost;
+	delivered = tp->delivered - bbr->lt_last_delivered;
+	/* Is loss rate (lost/delivered) >= lt_loss_thresh? If not, wait. */
+	if (!delivered || (lost << BBR_SCALE) < bbr_lt_loss_thresh * delivered)
+		return;
+
+	/* Find average delivery rate in this sampling interval. */
+	t = (s32)(tp->delivered_mstamp.stamp_jiffies - bbr->lt_last_stamp);
+	if (t < 1)
+		return;		/* interval is less than one jiffy, so wait */
+	t = jiffies_to_usecs(t);
+	/* Interval long enough for jiffies_to_usecs() to return a bogus 0? */
+	if (t < 1) {
+		bbr_reset_lt_bw_sampling(sk);  /* interval too long; reset */
+		return;
+	}
+	bw = (u64)delivered * BW_UNIT;
+	do_div(bw, t);
+	bbr_lt_bw_interval_done(sk, bw);
+}
+
+/* Estimate the bandwidth based on how fast packets are delivered */
+static void bbr_update_bw(struct sock *sk, const struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u64 bw;
+
+	bbr->round_start = 0;
+	if (rs->delivered < 0 || rs->interval_us <= 0)
+		return; /* Not a valid observation */
+
+	/* See if we've reached the next RTT */
+	if (!before(rs->prior_delivered, bbr->next_rtt_delivered)) {
+		bbr->next_rtt_delivered = tp->delivered;
+		bbr->rtt_cnt++;
+		bbr->round_start = 1;
+		bbr->packet_conservation = 0;
+	}
+
+	bbr_lt_bw_sampling(sk, rs);
+
+	/* Divide delivered by the interval to find a (lower bound) bottleneck
+	 * bandwidth sample. Delivered is in packets and interval_us in uS and
+	 * ratio will be <<1 for most connections. So delivered is first scaled.
+	 */
+	bw = (u64)rs->delivered * BW_UNIT;
+	do_div(bw, rs->interval_us);
+
+	/* If this sample is application-limited, it is likely to have a very
+	 * low delivered count that represents application behavior rather than
+	 * the available network rate. Such a sample could drag down estimated
+	 * bw, causing needless slow-down. Thus, to continue to send at the
+	 * last measured network rate, we filter out app-limited samples unless
+	 * they describe the path bw at least as well as our bw model.
+	 *
+	 * So the goal during app-limited phase is to proceed with the best
+	 * network rate no matter how long. We automatically leave this
+	 * phase when app writes faster than the network can deliver :)
+	 */
+	if (!rs->is_app_limited || bw >= bbr_max_bw(sk)) {
+		/* Incorporate new sample into our max bw filter. */
+		minmax_running_max(&bbr->bw, bbr_bw_rtts, bbr->rtt_cnt, bw);
+	}
+}
+
+/* Estimate when the pipe is full, using the change in delivery rate: BBR
+ * estimates that STARTUP filled the pipe if the estimated bw hasn't changed by
+ * at least bbr_full_bw_thresh (25%) after bbr_full_bw_cnt (3) non-app-limited
+ * rounds. Why 3 rounds: 1: rwin autotuning grows the rwin, 2: we fill the
+ * higher rwin, 3: we get higher delivery rate samples. Or transient
+ * cross-traffic or radio noise can go away. CUBIC Hystart shares a similar
+ * design goal, but uses delay and inter-ACK spacing instead of bandwidth.
+ */
+static void bbr_check_full_bw_reached(struct sock *sk,
+				      const struct rate_sample *rs)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 bw_thresh;
+
+	if (bbr_full_bw_reached(sk) || !bbr->round_start || rs->is_app_limited)
+		return;
+
+	bw_thresh = (u64)bbr->full_bw * bbr_full_bw_thresh >> BBR_SCALE;
+	if (bbr_max_bw(sk) >= bw_thresh) {
+		bbr->full_bw = bbr_max_bw(sk);
+		bbr->full_bw_cnt = 0;
+		return;
+	}
+	++bbr->full_bw_cnt;
+}
+
+/* If pipe is probably full, drain the queue and then enter steady-state. */
+static void bbr_check_drain(struct sock *sk, const struct rate_sample *rs)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	if (bbr->mode == BBR_STARTUP && bbr_full_bw_reached(sk)) {
+		bbr->mode = BBR_DRAIN;	/* drain queue we created */
+		bbr->pacing_gain = bbr_drain_gain;	/* pace slow to drain */
+		bbr->cwnd_gain = bbr_high_gain;	/* maintain cwnd */
+	}	/* fall through to check if in-flight is already small: */
+	if (bbr->mode == BBR_DRAIN &&
+	    tcp_packets_in_flight(tcp_sk(sk)) <=
+	    bbr_target_cwnd(sk, bbr_max_bw(sk), BBR_UNIT))
+		bbr_reset_probe_bw_mode(sk);  /* we estimate queue is drained */
+}
+
+/* The goal of PROBE_RTT mode is to have BBR flows cooperatively and
+ * periodically drain the bottleneck queue, to converge to measure the true
+ * min_rtt (unloaded propagation delay). This allows the flows to keep queues
+ * small (reducing queuing delay and packet loss) and achieve fairness among
+ * BBR flows.
+ *
+ * The min_rtt filter window is 10 seconds. When the min_rtt estimate expires,
+ * we enter PROBE_RTT mode and cap the cwnd at bbr_cwnd_min_target=4 packets.
+ * After at least bbr_probe_rtt_mode_ms=200ms and at least one packet-timed
+ * round trip elapsed with that flight size <= 4, we leave PROBE_RTT mode and
+ * re-enter the previous mode. BBR uses 200ms to approximately bound the
+ * performance penalty of PROBE_RTT's cwnd capping to roughly 2% (200ms/10s).
+ *
+ * Note that flows need only pay 2% if they are busy sending over the last 10
+ * seconds. Interactive applications (e.g., Web, RPCs, video chunks) often have
+ * natural silences or low-rate periods within 10 seconds where the rate is low
+ * enough for long enough to drain its queue in the bottleneck. We pick up
+ * these min RTT measurements opportunistically with our min_rtt filter. :-)
+ */
+static void bbr_update_min_rtt(struct sock *sk, const struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	bool filter_expired;
+
+	/* Track min RTT seen in the min_rtt_win_sec filter window: */
+	filter_expired = after(tcp_time_stamp,
+			       bbr->min_rtt_stamp + bbr_min_rtt_win_sec * HZ);
+	if (rs->rtt_us >= 0 &&
+	    (rs->rtt_us <= bbr->min_rtt_us || filter_expired)) {
+		bbr->min_rtt_us = rs->rtt_us;
+		bbr->min_rtt_stamp = tcp_time_stamp;
+	}
+
+	if (bbr_probe_rtt_mode_ms > 0 && filter_expired &&
+	    !bbr->idle_restart && bbr->mode != BBR_PROBE_RTT) {
+		bbr->mode = BBR_PROBE_RTT;  /* dip, drain queue */
+		bbr->pacing_gain = BBR_UNIT;
+		bbr->cwnd_gain = BBR_UNIT;
+		bbr_save_cwnd(sk);  /* note cwnd so we can restore it */
+		bbr->probe_rtt_done_stamp = 0;
+	}
+
+	if (bbr->mode == BBR_PROBE_RTT) {
+		/* Ignore low rate samples during this mode. */
+		tp->app_limited =
+			(tp->delivered + tcp_packets_in_flight(tp)) ? : 1;
+		/* Maintain min packets in flight for max(200 ms, 1 round). */
+		if (!bbr->probe_rtt_done_stamp &&
+		    tcp_packets_in_flight(tp) <= bbr_cwnd_min_target) {
+			bbr->probe_rtt_done_stamp = tcp_time_stamp +
+				msecs_to_jiffies(bbr_probe_rtt_mode_ms);
+			bbr->probe_rtt_round_done = 0;
+			bbr->next_rtt_delivered = tp->delivered;
+		} else if (bbr->probe_rtt_done_stamp) {
+			if (bbr->round_start)
+				bbr->probe_rtt_round_done = 1;
+			if (bbr->probe_rtt_round_done &&
+			    after(tcp_time_stamp, bbr->probe_rtt_done_stamp)) {
+				bbr->min_rtt_stamp = tcp_time_stamp;
+				bbr->restore_cwnd = 1;  /* snap to prior_cwnd */
+				bbr_reset_mode(sk);
+			}
+		}
+	}
+	bbr->idle_restart = 0;
+}
+
+static void bbr_update_model(struct sock *sk, const struct rate_sample *rs)
+{
+	bbr_update_bw(sk, rs);
+	bbr_update_cycle_phase(sk, rs);
+	bbr_check_full_bw_reached(sk, rs);
+	bbr_check_drain(sk, rs);
+	bbr_update_min_rtt(sk, rs);
+}
+
+static void bbr_main(struct sock *sk, const struct rate_sample *rs)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+	u32 bw;
+
+	bbr_update_model(sk, rs);
+
+	bw = bbr_bw(sk);
+	bbr_set_pacing_rate(sk, bw, bbr->pacing_gain);
+	bbr_set_tso_segs_goal(sk);
+	bbr_set_cwnd(sk, rs, rs->acked_sacked, bw, bbr->cwnd_gain);
+}
+
+static void bbr_init(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct bbr *bbr = inet_csk_ca(sk);
+	u64 bw;
+
+	bbr->prior_cwnd = 0;
+	bbr->tso_segs_goal = 0;	 /* default segs per skb until first ACK */
+	bbr->rtt_cnt = 0;
+	bbr->next_rtt_delivered = 0;
+	bbr->prev_ca_state = TCP_CA_Open;
+	bbr->packet_conservation = 0;
+
+	bbr->probe_rtt_done_stamp = 0;
+	bbr->probe_rtt_round_done = 0;
+	bbr->min_rtt_us = tcp_min_rtt(tp);
+	bbr->min_rtt_stamp = tcp_time_stamp;
+
+	minmax_reset(&bbr->bw, bbr->rtt_cnt, 0);  /* init max bw to 0 */
+
+	/* Initialize pacing rate to: high_gain * init_cwnd / RTT. */
+	bw = (u64)tp->snd_cwnd * BW_UNIT;
+	do_div(bw, (tp->srtt_us >> 3) ? : USEC_PER_MSEC);
+	sk->sk_pacing_rate = 0;		/* force an update of sk_pacing_rate */
+	bbr_set_pacing_rate(sk, bw, bbr_high_gain);
+
+	bbr->restore_cwnd = 0;
+	bbr->round_start = 0;
+	bbr->idle_restart = 0;
+	bbr->full_bw = 0;
+	bbr->full_bw_cnt = 0;
+	bbr->cycle_mstamp.v64 = 0;
+	bbr->cycle_idx = 0;
+	bbr_reset_lt_bw_sampling(sk);
+	bbr_reset_startup_mode(sk);
+}
+
+static u32 bbr_sndbuf_expand(struct sock *sk)
+{
+	/* Provision 3 * cwnd since BBR may slow-start even during recovery. */
+	return 3;
+}
+
+/* In theory BBR does not need to undo the cwnd since it does not
+ * always reduce cwnd on losses (see bbr_main()). Keep it for now.
+ */
+static u32 bbr_undo_cwnd(struct sock *sk)
+{
+	return tcp_sk(sk)->snd_cwnd;
+}
+
+/* Entering loss recovery, so save cwnd for when we exit or undo recovery. */
+static u32 bbr_ssthresh(struct sock *sk)
+{
+	bbr_save_cwnd(sk);
+	return TCP_INFINITE_SSTHRESH;	 /* BBR does not use ssthresh */
+}
+
+static size_t bbr_get_info(struct sock *sk, u32 ext, int *attr,
+			   union tcp_cc_info *info)
+{
+	if (ext & (1 << (INET_DIAG_BBRINFO - 1)) ||
+	    ext & (1 << (INET_DIAG_VEGASINFO - 1))) {
+		struct tcp_sock *tp = tcp_sk(sk);
+		struct bbr *bbr = inet_csk_ca(sk);
+		u64 bw = bbr_bw(sk);
+
+		bw = bw * tp->mss_cache * USEC_PER_SEC >> BW_SCALE;
+		memset(&info->bbr, 0, sizeof(info->bbr));
+		info->bbr.bbr_bw_lo		= (u32)bw;
+		info->bbr.bbr_bw_hi		= (u32)(bw >> 32);
+		info->bbr.bbr_min_rtt		= bbr->min_rtt_us;
+		info->bbr.bbr_pacing_gain	= bbr->pacing_gain;
+		info->bbr.bbr_cwnd_gain		= bbr->cwnd_gain;
+		*attr = INET_DIAG_BBRINFO;
+		return sizeof(info->bbr);
+	}
+	return 0;
+}
+
+static void bbr_set_state(struct sock *sk, u8 new_state)
+{
+	struct bbr *bbr = inet_csk_ca(sk);
+
+	if (new_state == TCP_CA_Loss) {
+		struct rate_sample rs = { .losses = 1 };
+
+		bbr->prev_ca_state = TCP_CA_Loss;
+		bbr->full_bw = 0;
+		bbr->round_start = 1;	/* treat RTO like end of a round */
+		bbr_lt_bw_sampling(sk, &rs);
+	}
+}
+
+static struct tcp_congestion_ops tcp_bbr_cong_ops __read_mostly = {
+	.flags		= TCP_CONG_NON_RESTRICTED,
+	.name		= "bbr",
+	.owner		= THIS_MODULE,
+	.init		= bbr_init,
+	.cong_control	= bbr_main,
+	.sndbuf_expand	= bbr_sndbuf_expand,
+	.undo_cwnd	= bbr_undo_cwnd,
+	.cwnd_event	= bbr_cwnd_event,
+	.ssthresh	= bbr_ssthresh,
+	.tso_segs_goal	= bbr_tso_segs_goal,
+	.get_info	= bbr_get_info,
+	.set_state	= bbr_set_state,
+};
+
+static int __init bbr_register(void)
+{
+	BUILD_BUG_ON(sizeof(struct bbr) > ICSK_CA_PRIV_SIZE);
+	return tcp_register_congestion_control(&tcp_bbr_cong_ops);
+}
+
+static void __exit bbr_unregister(void)
+{
+	tcp_unregister_congestion_control(&tcp_bbr_cong_ops);
+}
+
+module_init(bbr_register);
+module_exit(bbr_unregister);
+
+MODULE_AUTHOR("Van Jacobson <vanj@google.com>");
+MODULE_AUTHOR("Neal Cardwell <ncardwell@google.com>");
+MODULE_AUTHOR("Yuchung Cheng <ycheng@google.com>");
+MODULE_AUTHOR("Soheil Hassas Yeganeh <soheil@google.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("TCP BBR (Bottleneck Bandwidth and RTT)");
diff --git a/net/ipv4/tcp_cdg.c b/net/ipv4/tcp_cdg.c
index 03725b294286..35b280361cb2 100644
--- a/net/ipv4/tcp_cdg.c
+++ b/net/ipv4/tcp_cdg.c
@@ -56,7 +56,7 @@ MODULE_PARM_DESC(use_shadow, "use shadow window heuristic");
 module_param(use_tolerance, bool, 0644);
 MODULE_PARM_DESC(use_tolerance, "use loss tolerance heuristic");
 
-struct minmax {
+struct cdg_minmax {
 	union {
 		struct {
 			s32 min;
@@ -74,10 +74,10 @@ enum cdg_state {
 };
 
 struct cdg {
-	struct minmax rtt;
-	struct minmax rtt_prev;
-	struct minmax *gradients;
-	struct minmax gsum;
+	struct cdg_minmax rtt;
+	struct cdg_minmax rtt_prev;
+	struct cdg_minmax *gradients;
+	struct cdg_minmax gsum;
 	bool gfilled;
 	u8  tail;
 	u8  state;
@@ -353,7 +353,7 @@ static void tcp_cdg_cwnd_event(struct sock *sk, const enum tcp_ca_event ev)
 {
 	struct cdg *ca = inet_csk_ca(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct minmax *gradients;
+	struct cdg_minmax *gradients;
 
 	switch (ev) {
 	case CA_EVENT_CWND_RESTART:
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 882caa4e72bc..1294af4e0127 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -69,7 +69,7 @@ int tcp_register_congestion_control(struct tcp_congestion_ops *ca)
 	int ret = 0;
 
 	/* all algorithms must implement ssthresh and cong_avoid ops */
-	if (!ca->ssthresh || !ca->cong_avoid) {
+	if (!ca->ssthresh || !(ca->cong_avoid || ca->cong_control)) {
 		pr_err("%s does not implement required ops\n", ca->name);
 		return -EINVAL;
 	}
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 54d9f9b0120f..4e777a3243f9 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -150,6 +150,7 @@ void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb)
 	tp->segs_in = 0;
 	tcp_segs_in(tp, skb);
 	__skb_pull(skb, tcp_hdrlen(skb));
+	sk_forced_mem_schedule(sk, skb->truesize);
 	skb_set_owner_r(skb, sk);
 
 	TCP_SKB_CB(skb)->seq++;
@@ -226,6 +227,7 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk,
 	tcp_fastopen_add_skb(child, skb);
 
 	tcp_rsk(req)->rcv_nxt = tp->rcv_nxt;
+	tp->rcv_wup = tp->rcv_nxt;
 	/* tcp_conn_request() is sending the SYNACK,
 	 * and queues the child into listener accept queue.
 	 */
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index f3a9f3c2c8d8..8c6ad2d319d6 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -289,6 +289,7 @@ static bool tcp_ecn_rcv_ecn_echo(const struct tcp_sock *tp, const struct tcphdr
 static void tcp_sndbuf_expand(struct sock *sk)
 {
 	const struct tcp_sock *tp = tcp_sk(sk);
+	const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops;
 	int sndmem, per_mss;
 	u32 nr_segs;
 
@@ -309,7 +310,8 @@ static void tcp_sndbuf_expand(struct sock *sk)
 	 * Cubic needs 1.7 factor, rounded to 2 to include
 	 * extra cushion (application might react slowly to POLLOUT)
 	 */
-	sndmem = 2 * nr_segs * per_mss;
+	sndmem = ca_ops->sndbuf_expand ? ca_ops->sndbuf_expand(sk) : 2;
+	sndmem *= nr_segs * per_mss;
 
 	if (sk->sk_sndbuf < sndmem)
 		sk->sk_sndbuf = min(sndmem, sysctl_tcp_wmem[2]);
@@ -899,12 +901,29 @@ static void tcp_verify_retransmit_hint(struct tcp_sock *tp, struct sk_buff *skb)
 		tp->retransmit_high = TCP_SKB_CB(skb)->end_seq;
 }
 
+/* Sum the number of packets on the wire we have marked as lost.
+ * There are two cases we care about here:
+ * a) Packet hasn't been marked lost (nor retransmitted),
+ *    and this is the first loss.
+ * b) Packet has been marked both lost and retransmitted,
+ *    and this means we think it was lost again.
+ */
+static void tcp_sum_lost(struct tcp_sock *tp, struct sk_buff *skb)
+{
+	__u8 sacked = TCP_SKB_CB(skb)->sacked;
+
+	if (!(sacked & TCPCB_LOST) ||
+	    ((sacked & TCPCB_LOST) && (sacked & TCPCB_SACKED_RETRANS)))
+		tp->lost += tcp_skb_pcount(skb);
+}
+
 static void tcp_skb_mark_lost(struct tcp_sock *tp, struct sk_buff *skb)
 {
 	if (!(TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_ACKED))) {
 		tcp_verify_retransmit_hint(tp, skb);
 
 		tp->lost_out += tcp_skb_pcount(skb);
+		tcp_sum_lost(tp, skb);
 		TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
 	}
 }
@@ -913,6 +932,7 @@ void tcp_skb_mark_lost_uncond_verify(struct tcp_sock *tp, struct sk_buff *skb)
 {
 	tcp_verify_retransmit_hint(tp, skb);
 
+	tcp_sum_lost(tp, skb);
 	if (!(TCP_SKB_CB(skb)->sacked & (TCPCB_LOST|TCPCB_SACKED_ACKED))) {
 		tp->lost_out += tcp_skb_pcount(skb);
 		TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
@@ -1094,6 +1114,7 @@ struct tcp_sacktag_state {
 	 */
 	struct skb_mstamp first_sackt;
 	struct skb_mstamp last_sackt;
+	struct rate_sample *rate;
 	int	flag;
 };
 
@@ -1261,6 +1282,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
 	tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked,
 			start_seq, end_seq, dup_sack, pcount,
 			&skb->skb_mstamp);
+	tcp_rate_skb_delivered(sk, skb, state->rate);
 
 	if (skb == tp->lost_skb_hint)
 		tp->lost_cnt_hint += pcount;
@@ -1311,6 +1333,9 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb,
 		tcp_advance_highest_sack(sk, skb);
 
 	tcp_skb_collapse_tstamp(prev, skb);
+	if (unlikely(TCP_SKB_CB(prev)->tx.delivered_mstamp.v64))
+		TCP_SKB_CB(prev)->tx.delivered_mstamp.v64 = 0;
+
 	tcp_unlink_write_queue(skb, sk);
 	sk_wmem_free_skb(sk, skb);
 
@@ -1540,6 +1565,7 @@ static struct sk_buff *tcp_sacktag_walk(struct sk_buff *skb, struct sock *sk,
 						dup_sack,
 						tcp_skb_pcount(skb),
 						&skb->skb_mstamp);
+			tcp_rate_skb_delivered(sk, skb, state->rate);
 
 			if (!before(TCP_SKB_CB(skb)->seq,
 				    tcp_highest_sack_seq(tp)))
@@ -1622,8 +1648,10 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb,
 
 	found_dup_sack = tcp_check_dsack(sk, ack_skb, sp_wire,
 					 num_sacks, prior_snd_una);
-	if (found_dup_sack)
+	if (found_dup_sack) {
 		state->flag |= FLAG_DSACKING_ACK;
+		tp->delivered++; /* A spurious retransmission is delivered */
+	}
 
 	/* Eliminate too old ACKs, but take into
 	 * account more or less fresh ones, they can
@@ -1890,6 +1918,7 @@ void tcp_enter_loss(struct sock *sk)
 	struct sk_buff *skb;
 	bool new_recovery = icsk->icsk_ca_state < TCP_CA_Recovery;
 	bool is_reneg;			/* is receiver reneging on SACKs? */
+	bool mark_lost;
 
 	/* Reduce ssthresh if it has not yet been made inside this window. */
 	if (icsk->icsk_ca_state <= TCP_CA_Disorder ||
@@ -1923,8 +1952,12 @@ void tcp_enter_loss(struct sock *sk)
 		if (skb == tcp_send_head(sk))
 			break;
 
+		mark_lost = (!(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) ||
+			     is_reneg);
+		if (mark_lost)
+			tcp_sum_lost(tp, skb);
 		TCP_SKB_CB(skb)->sacked &= (~TCPCB_TAGBITS)|TCPCB_SACKED_ACKED;
-		if (!(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_ACKED) || is_reneg) {
+		if (mark_lost) {
 			TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_ACKED;
 			TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
 			tp->lost_out += tcp_skb_pcount(skb);
@@ -2503,6 +2536,9 @@ static inline void tcp_end_cwnd_reduction(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 
+	if (inet_csk(sk)->icsk_ca_ops->cong_control)
+		return;
+
 	/* Reset cwnd to ssthresh in CWR or Recovery (unless it's undone) */
 	if (inet_csk(sk)->icsk_ca_state == TCP_CA_CWR ||
 	    (tp->undo_marker && tp->snd_ssthresh < TCP_INFINITE_SSTHRESH)) {
@@ -2879,67 +2915,13 @@ static void tcp_fastretrans_alert(struct sock *sk, const int acked,
 	*rexmit = REXMIT_LOST;
 }
 
-/* Kathleen Nichols' algorithm for tracking the minimum value of
- * a data stream over some fixed time interval. (E.g., the minimum
- * RTT over the past five minutes.) It uses constant space and constant
- * time per update yet almost always delivers the same minimum as an
- * implementation that has to keep all the data in the window.
- *
- * The algorithm keeps track of the best, 2nd best & 3rd best min
- * values, maintaining an invariant that the measurement time of the
- * n'th best >= n-1'th best. It also makes sure that the three values
- * are widely separated in the time window since that bounds the worse
- * case error when that data is monotonically increasing over the window.
- *
- * Upon getting a new min, we can forget everything earlier because it
- * has no value - the new min is <= everything else in the window by
- * definition and it's the most recent. So we restart fresh on every new min
- * and overwrites 2nd & 3rd choices. The same property holds for 2nd & 3rd
- * best.
- */
 static void tcp_update_rtt_min(struct sock *sk, u32 rtt_us)
 {
-	const u32 now = tcp_time_stamp, wlen = sysctl_tcp_min_rtt_wlen * HZ;
-	struct rtt_meas *m = tcp_sk(sk)->rtt_min;
-	struct rtt_meas rttm = {
-		.rtt = likely(rtt_us) ? rtt_us : jiffies_to_usecs(1),
-		.ts = now,
-	};
-	u32 elapsed;
-
-	/* Check if the new measurement updates the 1st, 2nd, or 3rd choices */
-	if (unlikely(rttm.rtt <= m[0].rtt))
-		m[0] = m[1] = m[2] = rttm;
-	else if (rttm.rtt <= m[1].rtt)
-		m[1] = m[2] = rttm;
-	else if (rttm.rtt <= m[2].rtt)
-		m[2] = rttm;
-
-	elapsed = now - m[0].ts;
-	if (unlikely(elapsed > wlen)) {
-		/* Passed entire window without a new min so make 2nd choice
-		 * the new min & 3rd choice the new 2nd. So forth and so on.
-		 */
-		m[0] = m[1];
-		m[1] = m[2];
-		m[2] = rttm;
-		if (now - m[0].ts > wlen) {
-			m[0] = m[1];
-			m[1] = rttm;
-			if (now - m[0].ts > wlen)
-				m[0] = rttm;
-		}
-	} else if (m[1].ts == m[0].ts && elapsed > wlen / 4) {
-		/* Passed a quarter of the window without a new min so
-		 * take 2nd choice from the 2nd quarter of the window.
-		 */
-		m[2] = m[1] = rttm;
-	} else if (m[2].ts == m[1].ts && elapsed > wlen / 2) {
-		/* Passed half the window without a new min so take the 3rd
-		 * choice from the last half of the window.
-		 */
-		m[2] = rttm;
-	}
+	struct tcp_sock *tp = tcp_sk(sk);
+	u32 wlen = sysctl_tcp_min_rtt_wlen * HZ;
+
+	minmax_running_min(&tp->rtt_min, wlen, tcp_time_stamp,
+			   rtt_us ? : jiffies_to_usecs(1));
 }
 
 static inline bool tcp_ack_update_rtt(struct sock *sk, const int flag,
@@ -3102,10 +3084,11 @@ static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb,
  */
 static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
 			       u32 prior_snd_una, int *acked,
-			       struct tcp_sacktag_state *sack)
+			       struct tcp_sacktag_state *sack,
+			       struct skb_mstamp *now)
 {
 	const struct inet_connection_sock *icsk = inet_csk(sk);
-	struct skb_mstamp first_ackt, last_ackt, now;
+	struct skb_mstamp first_ackt, last_ackt;
 	struct tcp_sock *tp = tcp_sk(sk);
 	u32 prior_sacked = tp->sacked_out;
 	u32 reord = tp->packets_out;
@@ -3137,7 +3120,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
 			acked_pcount = tcp_tso_acked(sk, skb);
 			if (!acked_pcount)
 				break;
-
 			fully_acked = false;
 		} else {
 			/* Speedup tcp_unlink_write_queue() and next loop */
@@ -3173,6 +3155,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
 
 		tp->packets_out -= acked_pcount;
 		pkts_acked += acked_pcount;
+		tcp_rate_skb_delivered(sk, skb, sack->rate);
 
 		/* Initial outgoing SYN's get put onto the write_queue
 		 * just like anything else we transmit.  It is not
@@ -3205,16 +3188,15 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
 	if (skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED))
 		flag |= FLAG_SACK_RENEGING;
 
-	skb_mstamp_get(&now);
 	if (likely(first_ackt.v64) && !(flag & FLAG_RETRANS_DATA_ACKED)) {
-		seq_rtt_us = skb_mstamp_us_delta(&now, &first_ackt);
-		ca_rtt_us = skb_mstamp_us_delta(&now, &last_ackt);
+		seq_rtt_us = skb_mstamp_us_delta(now, &first_ackt);
+		ca_rtt_us = skb_mstamp_us_delta(now, &last_ackt);
 	}
 	if (sack->first_sackt.v64) {
-		sack_rtt_us = skb_mstamp_us_delta(&now, &sack->first_sackt);
-		ca_rtt_us = skb_mstamp_us_delta(&now, &sack->last_sackt);
+		sack_rtt_us = skb_mstamp_us_delta(now, &sack->first_sackt);
+		ca_rtt_us = skb_mstamp_us_delta(now, &sack->last_sackt);
 	}
-
+	sack->rate->rtt_us = ca_rtt_us; /* RTT of last (S)ACKed packet, or -1 */
 	rtt_update = tcp_ack_update_rtt(sk, flag, seq_rtt_us, sack_rtt_us,
 					ca_rtt_us);
 
@@ -3242,7 +3224,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets,
 		tp->fackets_out -= min(pkts_acked, tp->fackets_out);
 
 	} else if (skb && rtt_update && sack_rtt_us >= 0 &&
-		   sack_rtt_us > skb_mstamp_us_delta(&now, &skb->skb_mstamp)) {
+		   sack_rtt_us > skb_mstamp_us_delta(now, &skb->skb_mstamp)) {
 		/* Do not re-arm RTO if the sack RTT is measured from data sent
 		 * after when the head was last (re)transmitted. Otherwise the
 		 * timeout may continue to extend in loss recovery.
@@ -3333,8 +3315,15 @@ static inline bool tcp_may_raise_cwnd(const struct sock *sk, const int flag)
  * information. All transmission or retransmission are delayed afterwards.
  */
 static void tcp_cong_control(struct sock *sk, u32 ack, u32 acked_sacked,
-			     int flag)
+			     int flag, const struct rate_sample *rs)
 {
+	const struct inet_connection_sock *icsk = inet_csk(sk);
+
+	if (icsk->icsk_ca_ops->cong_control) {
+		icsk->icsk_ca_ops->cong_control(sk, rs);
+		return;
+	}
+
 	if (tcp_in_cwnd_reduction(sk)) {
 		/* Reduce cwnd if state mandates */
 		tcp_cwnd_reduction(sk, acked_sacked, flag);
@@ -3579,17 +3568,21 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 	struct tcp_sock *tp = tcp_sk(sk);
 	struct tcp_sacktag_state sack_state;
+	struct rate_sample rs = { .prior_delivered = 0 };
 	u32 prior_snd_una = tp->snd_una;
 	u32 ack_seq = TCP_SKB_CB(skb)->seq;
 	u32 ack = TCP_SKB_CB(skb)->ack_seq;
 	bool is_dupack = false;
 	u32 prior_fackets;
 	int prior_packets = tp->packets_out;
-	u32 prior_delivered = tp->delivered;
+	u32 delivered = tp->delivered;
+	u32 lost = tp->lost;
 	int acked = 0; /* Number of packets newly acked */
 	int rexmit = REXMIT_NONE; /* Flag to (re)transmit to recover losses */
+	struct skb_mstamp now;
 
 	sack_state.first_sackt.v64 = 0;
+	sack_state.rate = &rs;
 
 	/* We very likely will need to access write queue head. */
 	prefetchw(sk->sk_write_queue.next);
@@ -3612,6 +3605,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	if (after(ack, tp->snd_nxt))
 		goto invalid_ack;
 
+	skb_mstamp_get(&now);
+
 	if (icsk->icsk_pending == ICSK_TIME_EARLY_RETRANS ||
 	    icsk->icsk_pending == ICSK_TIME_LOSS_PROBE)
 		tcp_rearm_rto(sk);
@@ -3622,6 +3617,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 	}
 
 	prior_fackets = tp->fackets_out;
+	rs.prior_in_flight = tcp_packets_in_flight(tp);
 
 	/* ts_recent update must be made after we are sure that the packet
 	 * is in window.
@@ -3677,7 +3673,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 
 	/* See if we can take anything off of the retransmit queue. */
 	flag |= tcp_clean_rtx_queue(sk, prior_fackets, prior_snd_una, &acked,
-				    &sack_state);
+				    &sack_state, &now);
 
 	if (tcp_ack_is_dubious(sk, flag)) {
 		is_dupack = !(flag & (FLAG_SND_UNA_ADVANCED | FLAG_NOT_DUP));
@@ -3694,7 +3690,10 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
 
 	if (icsk->icsk_pending == ICSK_TIME_RETRANS)
 		tcp_schedule_loss_probe(sk);
-	tcp_cong_control(sk, ack, tp->delivered - prior_delivered, flag);
+	delivered = tp->delivered - delivered;	/* freshly ACKed or SACKed */
+	lost = tp->lost - lost;			/* freshly marked lost */
+	tcp_rate_gen(sk, delivered, lost, &now, &rs);
+	tcp_cong_control(sk, ack, delivered, flag, &rs);
 	tcp_xmit_recovery(sk, rexmit);
 	return 1;
 
@@ -4108,7 +4107,7 @@ void tcp_fin(struct sock *sk)
 	/* It _is_ possible, that we have something out-of-order _after_ FIN.
 	 * Probably, we should reset in this case. For now drop them.
 	 */
-	__skb_queue_purge(&tp->out_of_order_queue);
+	skb_rbtree_purge(&tp->out_of_order_queue);
 	if (tcp_is_sack(tp))
 		tcp_sack_reset(&tp->rx_opt);
 	sk_mem_reclaim(sk);
@@ -4268,7 +4267,7 @@ static void tcp_sack_remove(struct tcp_sock *tp)
 	int this_sack;
 
 	/* Empty ofo queue, hence, all the SACKs are eaten. Clear. */
-	if (skb_queue_empty(&tp->out_of_order_queue)) {
+	if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) {
 		tp->rx_opt.num_sacks = 0;
 		return;
 	}
@@ -4344,10 +4343,13 @@ static void tcp_ofo_queue(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
 	__u32 dsack_high = tp->rcv_nxt;
+	bool fin, fragstolen, eaten;
 	struct sk_buff *skb, *tail;
-	bool fragstolen, eaten;
+	struct rb_node *p;
 
-	while ((skb = skb_peek(&tp->out_of_order_queue)) != NULL) {
+	p = rb_first(&tp->out_of_order_queue);
+	while (p) {
+		skb = rb_entry(p, struct sk_buff, rbnode);
 		if (after(TCP_SKB_CB(skb)->seq, tp->rcv_nxt))
 			break;
 
@@ -4357,9 +4359,10 @@ static void tcp_ofo_queue(struct sock *sk)
 				dsack_high = TCP_SKB_CB(skb)->end_seq;
 			tcp_dsack_extend(sk, TCP_SKB_CB(skb)->seq, dsack);
 		}
+		p = rb_next(p);
+		rb_erase(&skb->rbnode, &tp->out_of_order_queue);
 
-		__skb_unlink(skb, &tp->out_of_order_queue);
-		if (!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt)) {
+		if (unlikely(!after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt))) {
 			SOCK_DEBUG(sk, "ofo packet was already received\n");
 			tcp_drop(sk, skb);
 			continue;
@@ -4371,12 +4374,19 @@ static void tcp_ofo_queue(struct sock *sk)
 		tail = skb_peek_tail(&sk->sk_receive_queue);
 		eaten = tail && tcp_try_coalesce(sk, tail, skb, &fragstolen);
 		tcp_rcv_nxt_update(tp, TCP_SKB_CB(skb)->end_seq);
+		fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN;
 		if (!eaten)
 			__skb_queue_tail(&sk->sk_receive_queue, skb);
-		if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
-			tcp_fin(sk);
-		if (eaten)
+		else
 			kfree_skb_partial(skb, fragstolen);
+
+		if (unlikely(fin)) {
+			tcp_fin(sk);
+			/* tcp_fin() purges tp->out_of_order_queue,
+			 * so we must end this loop right now.
+			 */
+			break;
+		}
 	}
 }
 
@@ -4403,8 +4413,10 @@ static int tcp_try_rmem_schedule(struct sock *sk, struct sk_buff *skb,
 static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
+	struct rb_node **p, *q, *parent;
 	struct sk_buff *skb1;
 	u32 seq, end_seq;
+	bool fragstolen;
 
 	tcp_ecn_check_ce(tp, skb);
 
@@ -4419,88 +4431,92 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 	inet_csk_schedule_ack(sk);
 
 	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOQUEUE);
+	seq = TCP_SKB_CB(skb)->seq;
+	end_seq = TCP_SKB_CB(skb)->end_seq;
 	SOCK_DEBUG(sk, "out of order segment: rcv_next %X seq %X - %X\n",
-		   tp->rcv_nxt, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq);
+		   tp->rcv_nxt, seq, end_seq);
 
-	skb1 = skb_peek_tail(&tp->out_of_order_queue);
-	if (!skb1) {
+	p = &tp->out_of_order_queue.rb_node;
+	if (RB_EMPTY_ROOT(&tp->out_of_order_queue)) {
 		/* Initial out of order segment, build 1 SACK. */
 		if (tcp_is_sack(tp)) {
 			tp->rx_opt.num_sacks = 1;
-			tp->selective_acks[0].start_seq = TCP_SKB_CB(skb)->seq;
-			tp->selective_acks[0].end_seq =
-						TCP_SKB_CB(skb)->end_seq;
+			tp->selective_acks[0].start_seq = seq;
+			tp->selective_acks[0].end_seq = end_seq;
 		}
-		__skb_queue_head(&tp->out_of_order_queue, skb);
+		rb_link_node(&skb->rbnode, NULL, p);
+		rb_insert_color(&skb->rbnode, &tp->out_of_order_queue);
+		tp->ooo_last_skb = skb;
 		goto end;
 	}
 
-	seq = TCP_SKB_CB(skb)->seq;
-	end_seq = TCP_SKB_CB(skb)->end_seq;
-
-	if (seq == TCP_SKB_CB(skb1)->end_seq) {
-		bool fragstolen;
-
-		if (!tcp_try_coalesce(sk, skb1, skb, &fragstolen)) {
-			__skb_queue_after(&tp->out_of_order_queue, skb1, skb);
-		} else {
-			tcp_grow_window(sk, skb);
-			kfree_skb_partial(skb, fragstolen);
-			skb = NULL;
-		}
-
-		if (!tp->rx_opt.num_sacks ||
-		    tp->selective_acks[0].end_seq != seq)
-			goto add_sack;
-
-		/* Common case: data arrive in order after hole. */
-		tp->selective_acks[0].end_seq = end_seq;
-		goto end;
-	}
-
-	/* Find place to insert this segment. */
-	while (1) {
-		if (!after(TCP_SKB_CB(skb1)->seq, seq))
-			break;
-		if (skb_queue_is_first(&tp->out_of_order_queue, skb1)) {
-			skb1 = NULL;
-			break;
-		}
-		skb1 = skb_queue_prev(&tp->out_of_order_queue, skb1);
-	}
-
-	/* Do skb overlap to previous one? */
-	if (skb1 && before(seq, TCP_SKB_CB(skb1)->end_seq)) {
-		if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) {
-			/* All the bits are present. Drop. */
-			NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
-			tcp_drop(sk, skb);
-			skb = NULL;
-			tcp_dsack_set(sk, seq, end_seq);
-			goto add_sack;
+	/* In the typical case, we are adding an skb to the end of the list.
+	 * Use of ooo_last_skb avoids the O(Log(N)) rbtree lookup.
+	 */
+	if (tcp_try_coalesce(sk, tp->ooo_last_skb, skb, &fragstolen)) {
+coalesce_done:
+		tcp_grow_window(sk, skb);
+		kfree_skb_partial(skb, fragstolen);
+		skb = NULL;
+		goto add_sack;
+	}
+	/* Can avoid an rbtree lookup if we are adding skb after ooo_last_skb */
+	if (!before(seq, TCP_SKB_CB(tp->ooo_last_skb)->end_seq)) {
+		parent = &tp->ooo_last_skb->rbnode;
+		p = &parent->rb_right;
+		goto insert;
+	}
+
+	/* Find place to insert this segment. Handle overlaps on the way. */
+	parent = NULL;
+	while (*p) {
+		parent = *p;
+		skb1 = rb_entry(parent, struct sk_buff, rbnode);
+		if (before(seq, TCP_SKB_CB(skb1)->seq)) {
+			p = &parent->rb_left;
+			continue;
 		}
-		if (after(seq, TCP_SKB_CB(skb1)->seq)) {
-			/* Partial overlap. */
-			tcp_dsack_set(sk, seq,
-				      TCP_SKB_CB(skb1)->end_seq);
-		} else {
-			if (skb_queue_is_first(&tp->out_of_order_queue,
-					       skb1))
-				skb1 = NULL;
-			else
-				skb1 = skb_queue_prev(
-					&tp->out_of_order_queue,
-					skb1);
+		if (before(seq, TCP_SKB_CB(skb1)->end_seq)) {
+			if (!after(end_seq, TCP_SKB_CB(skb1)->end_seq)) {
+				/* All the bits are present. Drop. */
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPOFOMERGE);
+				__kfree_skb(skb);
+				skb = NULL;
+				tcp_dsack_set(sk, seq, end_seq);
+				goto add_sack;
+			}
+			if (after(seq, TCP_SKB_CB(skb1)->seq)) {
+				/* Partial overlap. */
+				tcp_dsack_set(sk, seq, TCP_SKB_CB(skb1)->end_seq);
+			} else {
+				/* skb's seq == skb1's seq and skb covers skb1.
+				 * Replace skb1 with skb.
+				 */
+				rb_replace_node(&skb1->rbnode, &skb->rbnode,
+						&tp->out_of_order_queue);
+				tcp_dsack_extend(sk,
+						 TCP_SKB_CB(skb1)->seq,
+						 TCP_SKB_CB(skb1)->end_seq);
+				NET_INC_STATS(sock_net(sk),
+					      LINUX_MIB_TCPOFOMERGE);
+				__kfree_skb(skb1);
+				goto merge_right;
+			}
+		} else if (tcp_try_coalesce(sk, skb1, skb, &fragstolen)) {
+			goto coalesce_done;
 		}
+		p = &parent->rb_right;
 	}
-	if (!skb1)
-		__skb_queue_head(&tp->out_of_order_queue, skb);
-	else
-		__skb_queue_after(&tp->out_of_order_queue, skb1, skb);
+insert:
+	/* Insert segment into RB tree. */
+	rb_link_node(&skb->rbnode, parent, p);
+	rb_insert_color(&skb->rbnode, &tp->out_of_order_queue);
 
-	/* And clean segments covered by new one as whole. */
-	while (!skb_queue_is_last(&tp->out_of_order_queue, skb)) {
-		skb1 = skb_queue_next(&tp->out_of_order_queue, skb);
+merge_right:
+	/* Remove other segments covered by skb. */
+	while ((q = rb_next(&skb->rbnode)) != NULL) {
+		skb1 = rb_entry(q, struct sk_buff, rbnode);
 
 		if (!after(end_seq, TCP_SKB_CB(skb1)->seq))
 			break;
@@ -4509,12 +4525,15 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb)
 					 end_seq);
 			break;
 		}
-		__skb_unlink(skb1, &tp->out_of_order_queue);
+		rb_erase(&skb1->rbnode, &tp->out_of_order_queue);
 		tcp_dsack_extend(sk, TCP_SKB_CB(skb1)->seq,
 				 TCP_SKB_CB(skb1)->end_seq);
 		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPOFOMERGE);
 		tcp_drop(sk, skb1);
 	}
+	/* If there is no skb after us, we are the last_skb ! */
+	if (!q)
+		tp->ooo_last_skb = skb;
 
 add_sack:
 	if (tcp_is_sack(tp))
@@ -4651,13 +4670,13 @@ queue_and_out:
 		if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
 			tcp_fin(sk);
 
-		if (!skb_queue_empty(&tp->out_of_order_queue)) {
+		if (!RB_EMPTY_ROOT(&tp->out_of_order_queue)) {
 			tcp_ofo_queue(sk);
 
 			/* RFC2581. 4.2. SHOULD send immediate ACK, when
 			 * gap in queue is filled.
 			 */
-			if (skb_queue_empty(&tp->out_of_order_queue))
+			if (RB_EMPTY_ROOT(&tp->out_of_order_queue))
 				inet_csk(sk)->icsk_ack.pingpong = 0;
 		}
 
@@ -4711,48 +4730,76 @@ drop:
 	tcp_data_queue_ofo(sk, skb);
 }
 
+static struct sk_buff *tcp_skb_next(struct sk_buff *skb, struct sk_buff_head *list)
+{
+	if (list)
+		return !skb_queue_is_last(list, skb) ? skb->next : NULL;
+
+	return rb_entry_safe(rb_next(&skb->rbnode), struct sk_buff, rbnode);
+}
+
 static struct sk_buff *tcp_collapse_one(struct sock *sk, struct sk_buff *skb,
-					struct sk_buff_head *list)
+					struct sk_buff_head *list,
+					struct rb_root *root)
 {
-	struct sk_buff *next = NULL;
+	struct sk_buff *next = tcp_skb_next(skb, list);
 
-	if (!skb_queue_is_last(list, skb))
-		next = skb_queue_next(list, skb);
+	if (list)
+		__skb_unlink(skb, list);
+	else
+		rb_erase(&skb->rbnode, root);
 
-	__skb_unlink(skb, list);
 	__kfree_skb(skb);
 	NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRCVCOLLAPSED);
 
 	return next;
 }
 
+/* Insert skb into rb tree, ordered by TCP_SKB_CB(skb)->seq */
+static void tcp_rbtree_insert(struct rb_root *root, struct sk_buff *skb)
+{
+	struct rb_node **p = &root->rb_node;
+	struct rb_node *parent = NULL;
+	struct sk_buff *skb1;
+
+	while (*p) {
+		parent = *p;
+		skb1 = rb_entry(parent, struct sk_buff, rbnode);
+		if (before(TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb1)->seq))
+			p = &parent->rb_left;
+		else
+			p = &parent->rb_right;
+	}
+	rb_link_node(&skb->rbnode, parent, p);
+	rb_insert_color(&skb->rbnode, root);
+}
+
 /* Collapse contiguous sequence of skbs head..tail with
  * sequence numbers start..end.
  *
- * If tail is NULL, this means until the end of the list.
+ * If tail is NULL, this means until the end of the queue.
  *
  * Segments with FIN/SYN are not collapsed (only because this
  * simplifies code)
  */
 static void
-tcp_collapse(struct sock *sk, struct sk_buff_head *list,
-	     struct sk_buff *head, struct sk_buff *tail,
-	     u32 start, u32 end)
+tcp_collapse(struct sock *sk, struct sk_buff_head *list, struct rb_root *root,
+	     struct sk_buff *head, struct sk_buff *tail, u32 start, u32 end)
 {
-	struct sk_buff *skb, *n;
+	struct sk_buff *skb = head, *n;
+	struct sk_buff_head tmp;
 	bool end_of_skbs;
 
 	/* First, check that queue is collapsible and find
-	 * the point where collapsing can be useful. */
-	skb = head;
+	 * the point where collapsing can be useful.
+	 */
 restart:
-	end_of_skbs = true;
-	skb_queue_walk_from_safe(list, skb, n) {
-		if (skb == tail)
-			break;
+	for (end_of_skbs = true; skb != NULL && skb != tail; skb = n) {
+		n = tcp_skb_next(skb, list);
+
 		/* No new bits? It is possible on ofo queue. */
 		if (!before(start, TCP_SKB_CB(skb)->end_seq)) {
-			skb = tcp_collapse_one(sk, skb, list);
+			skb = tcp_collapse_one(sk, skb, list, root);
 			if (!skb)
 				break;
 			goto restart;
@@ -4770,13 +4817,10 @@ restart:
 			break;
 		}
 
-		if (!skb_queue_is_last(list, skb)) {
-			struct sk_buff *next = skb_queue_next(list, skb);
-			if (next != tail &&
-			    TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(next)->seq) {
-				end_of_skbs = false;
-				break;
-			}
+		if (n && n != tail &&
+		    TCP_SKB_CB(skb)->end_seq != TCP_SKB_CB(n)->seq) {
+			end_of_skbs = false;
+			break;
 		}
 
 		/* Decided to skip this, advance start seq. */
@@ -4786,17 +4830,22 @@ restart:
 	    (TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN)))
 		return;
 
+	__skb_queue_head_init(&tmp);
+
 	while (before(start, end)) {
 		int copy = min_t(int, SKB_MAX_ORDER(0, 0), end - start);
 		struct sk_buff *nskb;
 
 		nskb = alloc_skb(copy, GFP_ATOMIC);
 		if (!nskb)
-			return;
+			break;
 
 		memcpy(nskb->cb, skb->cb, sizeof(skb->cb));
 		TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start;
-		__skb_queue_before(list, skb, nskb);
+		if (list)
+			__skb_queue_before(list, skb, nskb);
+		else
+			__skb_queue_tail(&tmp, nskb); /* defer rbtree insertion */
 		skb_set_owner_r(nskb, sk);
 
 		/* Copy data, releasing collapsed skbs. */
@@ -4814,14 +4863,17 @@ restart:
 				start += size;
 			}
 			if (!before(start, TCP_SKB_CB(skb)->end_seq)) {
-				skb = tcp_collapse_one(sk, skb, list);
+				skb = tcp_collapse_one(sk, skb, list, root);
 				if (!skb ||
 				    skb == tail ||
 				    (TCP_SKB_CB(skb)->tcp_flags & (TCPHDR_SYN | TCPHDR_FIN)))
-					return;
+					goto end;
 			}
 		}
 	}
+end:
+	skb_queue_walk_safe(&tmp, skb, n)
+		tcp_rbtree_insert(root, skb);
 }
 
 /* Collapse ofo queue. Algorithm: select contiguous sequence of skbs
@@ -4830,43 +4882,43 @@ restart:
 static void tcp_collapse_ofo_queue(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct sk_buff *skb = skb_peek(&tp->out_of_order_queue);
-	struct sk_buff *head;
+	struct sk_buff *skb, *head;
+	struct rb_node *p;
 	u32 start, end;
 
-	if (!skb)
+	p = rb_first(&tp->out_of_order_queue);
+	skb = rb_entry_safe(p, struct sk_buff, rbnode);
+new_range:
+	if (!skb) {
+		p = rb_last(&tp->out_of_order_queue);
+		/* Note: This is possible p is NULL here. We do not
+		 * use rb_entry_safe(), as ooo_last_skb is valid only
+		 * if rbtree is not empty.
+		 */
+		tp->ooo_last_skb = rb_entry(p, struct sk_buff, rbnode);
 		return;
-
+	}
 	start = TCP_SKB_CB(skb)->seq;
 	end = TCP_SKB_CB(skb)->end_seq;
-	head = skb;
-
-	for (;;) {
-		struct sk_buff *next = NULL;
 
-		if (!skb_queue_is_last(&tp->out_of_order_queue, skb))
-			next = skb_queue_next(&tp->out_of_order_queue, skb);
-		skb = next;
+	for (head = skb;;) {
+		skb = tcp_skb_next(skb, NULL);
 
-		/* Segment is terminated when we see gap or when
-		 * we are at the end of all the queue. */
+		/* Range is terminated when we see a gap or when
+		 * we are at the queue end.
+		 */
 		if (!skb ||
 		    after(TCP_SKB_CB(skb)->seq, end) ||
 		    before(TCP_SKB_CB(skb)->end_seq, start)) {
-			tcp_collapse(sk, &tp->out_of_order_queue,
+			tcp_collapse(sk, NULL, &tp->out_of_order_queue,
 				     head, skb, start, end);
-			head = skb;
-			if (!skb)
-				break;
-			/* Start new segment */
+			goto new_range;
+		}
+
+		if (unlikely(before(TCP_SKB_CB(skb)->seq, start)))
 			start = TCP_SKB_CB(skb)->seq;
+		if (after(TCP_SKB_CB(skb)->end_seq, end))
 			end = TCP_SKB_CB(skb)->end_seq;
-		} else {
-			if (before(TCP_SKB_CB(skb)->seq, start))
-				start = TCP_SKB_CB(skb)->seq;
-			if (after(TCP_SKB_CB(skb)->end_seq, end))
-				end = TCP_SKB_CB(skb)->end_seq;
-		}
 	}
 }
 
@@ -4883,20 +4935,24 @@ static void tcp_collapse_ofo_queue(struct sock *sk)
 static bool tcp_prune_ofo_queue(struct sock *sk)
 {
 	struct tcp_sock *tp = tcp_sk(sk);
-	struct sk_buff *skb;
+	struct rb_node *node, *prev;
 
-	if (skb_queue_empty(&tp->out_of_order_queue))
+	if (RB_EMPTY_ROOT(&tp->out_of_order_queue))
 		return false;
 
 	NET_INC_STATS(sock_net(sk), LINUX_MIB_OFOPRUNED);
-
-	while ((skb = __skb_dequeue_tail(&tp->out_of_order_queue)) != NULL) {
-		tcp_drop(sk, skb);
+	node = &tp->ooo_last_skb->rbnode;
+	do {
+		prev = rb_prev(node);
+		rb_erase(node, &tp->out_of_order_queue);
+		tcp_drop(sk, rb_entry(node, struct sk_buff, rbnode));
 		sk_mem_reclaim(sk);
 		if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
 		    !tcp_under_memory_pressure(sk))
 			break;
-	}
+		node = prev;
+	} while (node);
+	tp->ooo_last_skb = rb_entry(prev, struct sk_buff, rbnode);
 
 	/* Reset SACK state.  A conforming SACK implementation will
 	 * do the same at a timeout based retransmit.  When a connection
@@ -4930,7 +4986,7 @@ static int tcp_prune_queue(struct sock *sk)
 
 	tcp_collapse_ofo_queue(sk);
 	if (!skb_queue_empty(&sk->sk_receive_queue))
-		tcp_collapse(sk, &sk->sk_receive_queue,
+		tcp_collapse(sk, &sk->sk_receive_queue, NULL,
 			     skb_peek(&sk->sk_receive_queue),
 			     NULL,
 			     tp->copied_seq, tp->rcv_nxt);
@@ -5035,7 +5091,7 @@ static void __tcp_ack_snd_check(struct sock *sk, int ofo_possible)
 	    /* We ACK each frame or... */
 	    tcp_in_quickack_mode(sk) ||
 	    /* We have out of order data. */
-	    (ofo_possible && skb_peek(&tp->out_of_order_queue))) {
+	    (ofo_possible && !RB_EMPTY_ROOT(&tp->out_of_order_queue))) {
 		/* Then ack it now */
 		tcp_send_ack(sk);
 	} else {
@@ -5894,7 +5950,7 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		 * so release it.
 		 */
 		if (req) {
-			tp->total_retrans = req->num_retrans;
+			inet_csk(sk)->icsk_retransmits = 0;
 			reqsk_fastopen_remove(sk, req, false);
 		} else {
 			/* Make sure socket is routed, for correct metrics. */
@@ -5936,7 +5992,8 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb)
 		} else
 			tcp_init_metrics(sk);
 
-		tcp_update_pacing_rate(sk);
+		if (!inet_csk(sk)->icsk_ca_ops->cong_control)
+			tcp_update_pacing_rate(sk);
 
 		/* Prevent spurious tcp_cwnd_restart() on first data packet */
 		tp->lsndtime = tcp_time_stamp;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 13b05adf9d3e..7ac37c314312 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1844,7 +1844,7 @@ void tcp_v4_destroy_sock(struct sock *sk)
 	tcp_write_queue_purge(sk);
 
 	/* Cleans up our, hopefully empty, out_of_order_queue. */
-	__skb_queue_purge(&tp->out_of_order_queue);
+	skb_rbtree_purge(&tp->out_of_order_queue);
 
 #ifdef CONFIG_TCP_MD5SIG
 	/* Clean up the MD5 key list, if any */
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 4b95ec4ed2c8..6234ebaa7db1 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -464,7 +464,7 @@ struct sock *tcp_create_openreq_child(const struct sock *sk,
 
 		newtp->srtt_us = 0;
 		newtp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT);
-		newtp->rtt_min[0].rtt = ~0U;
+		minmax_reset(&newtp->rtt_min, tcp_time_stamp, ~0U);
 		newicsk->icsk_rto = TCP_TIMEOUT_INIT;
 
 		newtp->packets_out = 0;
@@ -487,8 +487,10 @@ struct sock *tcp_create_openreq_child(const struct sock *sk,
 		newtp->snd_cwnd = TCP_INIT_CWND;
 		newtp->snd_cwnd_cnt = 0;
 
+		/* There's a bubble in the pipe until at least the first ACK. */
+		newtp->app_limited = ~0U;
+
 		tcp_init_xmit_timers(newsk);
-		__skb_queue_head_init(&newtp->out_of_order_queue);
 		newtp->write_seq = newtp->pushed_seq = treq->snt_isn + 1;
 
 		newtp->rx_opt.saw_tstamp = 0;
diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c
index 5c5964962d0c..bc68da38ea86 100644
--- a/net/ipv4/tcp_offload.c
+++ b/net/ipv4/tcp_offload.c
@@ -90,12 +90,6 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb,
 		goto out;
 	}
 
-	/* GSO partial only requires splitting the frame into an MSS
-	 * multiple and possibly a remainder.  So update the mss now.
-	 */
-	if (features & NETIF_F_GSO_PARTIAL)
-		mss = skb->len - (skb->len % mss);
-
 	copy_destructor = gso_skb->destructor == tcp_wfree;
 	ooo_okay = gso_skb->ooo_okay;
 	/* All segments but the first should have ooo_okay cleared */
@@ -108,6 +102,13 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb,
 	/* Only first segment might have ooo_okay set */
 	segs->ooo_okay = ooo_okay;
 
+	/* GSO partial and frag_list segmentation only requires splitting
+	 * the frame into an MSS multiple and possibly a remainder, both
+	 * cases return a GSO skb. So update the mss now.
+	 */
+	if (skb_is_gso(segs))
+		mss *= skb_shinfo(segs)->gso_segs;
+
 	delta = htonl(oldlen + (thlen + mss));
 
 	skb = segs;
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 8b45794eb6b2..7c777089a4d6 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -734,9 +734,16 @@ static void tcp_tsq_handler(struct sock *sk)
 {
 	if ((1 << sk->sk_state) &
 	    (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_CLOSING |
-	     TCPF_CLOSE_WAIT  | TCPF_LAST_ACK))
-		tcp_write_xmit(sk, tcp_current_mss(sk), tcp_sk(sk)->nonagle,
+	     TCPF_CLOSE_WAIT  | TCPF_LAST_ACK)) {
+		struct tcp_sock *tp = tcp_sk(sk);
+
+		if (tp->lost_out > tp->retrans_out &&
+		    tp->snd_cwnd > tcp_packets_in_flight(tp))
+			tcp_xmit_retransmit_queue(sk);
+
+		tcp_write_xmit(sk, tcp_current_mss(sk), tp->nonagle,
 			       0, GFP_ATOMIC);
+	}
 }
 /*
  * One tasklet per cpu tries to send more skbs.
@@ -918,6 +925,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
 		skb_mstamp_get(&skb->skb_mstamp);
 		TCP_SKB_CB(skb)->tx.in_flight = TCP_SKB_CB(skb)->end_seq
 			- tp->snd_una;
+		tcp_rate_skb_sent(sk, skb);
 
 		if (unlikely(skb_cloned(skb)))
 			skb = pskb_copy(skb, gfp_mask);
@@ -1213,6 +1221,9 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len,
 	tcp_set_skb_tso_segs(skb, mss_now);
 	tcp_set_skb_tso_segs(buff, mss_now);
 
+	/* Update delivered info for the new segment */
+	TCP_SKB_CB(buff)->tx = TCP_SKB_CB(skb)->tx;
+
 	/* If this packet has been sent out already, we must
 	 * adjust the various packet counters.
 	 */
@@ -1358,6 +1369,7 @@ int tcp_mss_to_mtu(struct sock *sk, int mss)
 	}
 	return mtu;
 }
+EXPORT_SYMBOL(tcp_mss_to_mtu);
 
 /* MTU probing init per socket */
 void tcp_mtup_init(struct sock *sk)
@@ -1545,7 +1557,8 @@ static bool tcp_nagle_check(bool partial, const struct tcp_sock *tp,
 /* Return how many segs we'd like on a TSO packet,
  * to send one TSO packet per ms
  */
-static u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now)
+u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now,
+		     int min_tso_segs)
 {
 	u32 bytes, segs;
 
@@ -1557,10 +1570,23 @@ static u32 tcp_tso_autosize(const struct sock *sk, unsigned int mss_now)
 	 * This preserves ACK clocking and is consistent
 	 * with tcp_tso_should_defer() heuristic.
 	 */
-	segs = max_t(u32, bytes / mss_now, sysctl_tcp_min_tso_segs);
+	segs = max_t(u32, bytes / mss_now, min_tso_segs);
 
 	return min_t(u32, segs, sk->sk_gso_max_segs);
 }
+EXPORT_SYMBOL(tcp_tso_autosize);
+
+/* Return the number of segments we want in the skb we are transmitting.
+ * See if congestion control module wants to decide; otherwise, autosize.
+ */
+static u32 tcp_tso_segs(struct sock *sk, unsigned int mss_now)
+{
+	const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops;
+	u32 tso_segs = ca_ops->tso_segs_goal ? ca_ops->tso_segs_goal(sk) : 0;
+
+	return tso_segs ? :
+		tcp_tso_autosize(sk, mss_now, sysctl_tcp_min_tso_segs);
+}
 
 /* Returns the portion of skb which can be sent right away */
 static unsigned int tcp_mss_split_point(const struct sock *sk,
@@ -2020,6 +2046,39 @@ static int tcp_mtu_probe(struct sock *sk)
 	return -1;
 }
 
+/* TCP Small Queues :
+ * Control number of packets in qdisc/devices to two packets / or ~1 ms.
+ * (These limits are doubled for retransmits)
+ * This allows for :
+ *  - better RTT estimation and ACK scheduling
+ *  - faster recovery
+ *  - high rates
+ * Alas, some drivers / subsystems require a fair amount
+ * of queued bytes to ensure line rate.
+ * One example is wifi aggregation (802.11 AMPDU)
+ */
+static bool tcp_small_queue_check(struct sock *sk, const struct sk_buff *skb,
+				  unsigned int factor)
+{
+	unsigned int limit;
+
+	limit = max(2 * skb->truesize, sk->sk_pacing_rate >> 10);
+	limit = min_t(u32, limit, sysctl_tcp_limit_output_bytes);
+	limit <<= factor;
+
+	if (atomic_read(&sk->sk_wmem_alloc) > limit) {
+		set_bit(TSQ_THROTTLED, &tcp_sk(sk)->tsq_flags);
+		/* It is possible TX completion already happened
+		 * before we set TSQ_THROTTLED, so we must
+		 * test again the condition.
+		 */
+		smp_mb__after_atomic();
+		if (atomic_read(&sk->sk_wmem_alloc) > limit)
+			return true;
+	}
+	return false;
+}
+
 /* This routine writes packets to the network.  It advances the
  * send_head.  This happens as incoming acks open up the remote
  * window for us.
@@ -2057,7 +2116,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
 		}
 	}
 
-	max_segs = tcp_tso_autosize(sk, mss_now);
+	max_segs = tcp_tso_segs(sk, mss_now);
 	while ((skb = tcp_send_head(sk))) {
 		unsigned int limit;
 
@@ -2106,29 +2165,8 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
 		    unlikely(tso_fragment(sk, skb, limit, mss_now, gfp)))
 			break;
 
-		/* TCP Small Queues :
-		 * Control number of packets in qdisc/devices to two packets / or ~1 ms.
-		 * This allows for :
-		 *  - better RTT estimation and ACK scheduling
-		 *  - faster recovery
-		 *  - high rates
-		 * Alas, some drivers / subsystems require a fair amount
-		 * of queued bytes to ensure line rate.
-		 * One example is wifi aggregation (802.11 AMPDU)
-		 */
-		limit = max(2 * skb->truesize, sk->sk_pacing_rate >> 10);
-		limit = min_t(u32, limit, sysctl_tcp_limit_output_bytes);
-
-		if (atomic_read(&sk->sk_wmem_alloc) > limit) {
-			set_bit(TSQ_THROTTLED, &tp->tsq_flags);
-			/* It is possible TX completion already happened
-			 * before we set TSQ_THROTTLED, so we must
-			 * test again the condition.
-			 */
-			smp_mb__after_atomic();
-			if (atomic_read(&sk->sk_wmem_alloc) > limit)
-				break;
-		}
+		if (tcp_small_queue_check(sk, skb, 0))
+			break;
 
 		if (unlikely(tcp_transmit_skb(sk, skb, 1, gfp)))
 			break;
@@ -2605,7 +2643,8 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 	 * copying overhead: fragmentation, tunneling, mangling etc.
 	 */
 	if (atomic_read(&sk->sk_wmem_alloc) >
-	    min(sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2), sk->sk_sndbuf))
+	    min_t(u32, sk->sk_wmem_queued + (sk->sk_wmem_queued >> 2),
+		  sk->sk_sndbuf))
 		return -EAGAIN;
 
 	if (skb_still_in_host_queue(sk, skb))
@@ -2774,7 +2813,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
 		last_lost = tp->snd_una;
 	}
 
-	max_segs = tcp_tso_autosize(sk, tcp_current_mss(sk));
+	max_segs = tcp_tso_segs(sk, tcp_current_mss(sk));
 	tcp_for_write_queue_from(skb, sk) {
 		__u8 sacked;
 		int segs;
@@ -2828,10 +2867,13 @@ begin_fwd:
 		if (sacked & (TCPCB_SACKED_ACKED|TCPCB_SACKED_RETRANS))
 			continue;
 
+		if (tcp_small_queue_check(sk, skb, 1))
+			return;
+
 		if (tcp_retransmit_skb(sk, skb, segs))
 			return;
 
-		NET_INC_STATS(sock_net(sk), mib_idx);
+		NET_ADD_STATS(sock_net(sk), mib_idx, tcp_skb_pcount(skb));
 
 		if (tcp_in_cwnd_reduction(sk))
 			tp->prr_out += tcp_skb_pcount(skb);
@@ -3568,6 +3610,8 @@ int tcp_rtx_synack(const struct sock *sk, struct request_sock *req)
 	if (!res) {
 		__TCP_INC_STATS(sock_net(sk), TCP_MIB_RETRANSSEGS);
 		__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPSYNRETRANS);
+		if (unlikely(tcp_passive_fastopen(sk)))
+			tcp_sk(sk)->total_retrans++;
 	}
 	return res;
 }
diff --git a/net/ipv4/tcp_rate.c b/net/ipv4/tcp_rate.c
new file mode 100644
index 000000000000..9be1581a5a08
--- /dev/null
+++ b/net/ipv4/tcp_rate.c
@@ -0,0 +1,186 @@
+#include <net/tcp.h>
+
+/* The bandwidth estimator estimates the rate at which the network
+ * can currently deliver outbound data packets for this flow. At a high
+ * level, it operates by taking a delivery rate sample for each ACK.
+ *
+ * A rate sample records the rate at which the network delivered packets
+ * for this flow, calculated over the time interval between the transmission
+ * of a data packet and the acknowledgment of that packet.
+ *
+ * Specifically, over the interval between each transmit and corresponding ACK,
+ * the estimator generates a delivery rate sample. Typically it uses the rate
+ * at which packets were acknowledged. However, the approach of using only the
+ * acknowledgment rate faces a challenge under the prevalent ACK decimation or
+ * compression: packets can temporarily appear to be delivered much quicker
+ * than the bottleneck rate. Since it is physically impossible to do that in a
+ * sustained fashion, when the estimator notices that the ACK rate is faster
+ * than the transmit rate, it uses the latter:
+ *
+ *    send_rate = #pkts_delivered/(last_snd_time - first_snd_time)
+ *    ack_rate  = #pkts_delivered/(last_ack_time - first_ack_time)
+ *    bw = min(send_rate, ack_rate)
+ *
+ * Notice the estimator essentially estimates the goodput, not always the
+ * network bottleneck link rate when the sending or receiving is limited by
+ * other factors like applications or receiver window limits.  The estimator
+ * deliberately avoids using the inter-packet spacing approach because that
+ * approach requires a large number of samples and sophisticated filtering.
+ *
+ * TCP flows can often be application-limited in request/response workloads.
+ * The estimator marks a bandwidth sample as application-limited if there
+ * was some moment during the sampled window of packets when there was no data
+ * ready to send in the write queue.
+ */
+
+/* Snapshot the current delivery information in the skb, to generate
+ * a rate sample later when the skb is (s)acked in tcp_rate_skb_delivered().
+ */
+void tcp_rate_skb_sent(struct sock *sk, struct sk_buff *skb)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+
+	 /* In general we need to start delivery rate samples from the
+	  * time we received the most recent ACK, to ensure we include
+	  * the full time the network needs to deliver all in-flight
+	  * packets. If there are no packets in flight yet, then we
+	  * know that any ACKs after now indicate that the network was
+	  * able to deliver those packets completely in the sampling
+	  * interval between now and the next ACK.
+	  *
+	  * Note that we use packets_out instead of tcp_packets_in_flight(tp)
+	  * because the latter is a guess based on RTO and loss-marking
+	  * heuristics. We don't want spurious RTOs or loss markings to cause
+	  * a spuriously small time interval, causing a spuriously high
+	  * bandwidth estimate.
+	  */
+	if (!tp->packets_out) {
+		tp->first_tx_mstamp  = skb->skb_mstamp;
+		tp->delivered_mstamp = skb->skb_mstamp;
+	}
+
+	TCP_SKB_CB(skb)->tx.first_tx_mstamp	= tp->first_tx_mstamp;
+	TCP_SKB_CB(skb)->tx.delivered_mstamp	= tp->delivered_mstamp;
+	TCP_SKB_CB(skb)->tx.delivered		= tp->delivered;
+	TCP_SKB_CB(skb)->tx.is_app_limited	= tp->app_limited ? 1 : 0;
+}
+
+/* When an skb is sacked or acked, we fill in the rate sample with the (prior)
+ * delivery information when the skb was last transmitted.
+ *
+ * If an ACK (s)acks multiple skbs (e.g., stretched-acks), this function is
+ * called multiple times. We favor the information from the most recently
+ * sent skb, i.e., the skb with the highest prior_delivered count.
+ */
+void tcp_rate_skb_delivered(struct sock *sk, struct sk_buff *skb,
+			    struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct tcp_skb_cb *scb = TCP_SKB_CB(skb);
+
+	if (!scb->tx.delivered_mstamp.v64)
+		return;
+
+	if (!rs->prior_delivered ||
+	    after(scb->tx.delivered, rs->prior_delivered)) {
+		rs->prior_delivered  = scb->tx.delivered;
+		rs->prior_mstamp     = scb->tx.delivered_mstamp;
+		rs->is_app_limited   = scb->tx.is_app_limited;
+		rs->is_retrans	     = scb->sacked & TCPCB_RETRANS;
+
+		/* Find the duration of the "send phase" of this window: */
+		rs->interval_us      = skb_mstamp_us_delta(
+						&skb->skb_mstamp,
+						&scb->tx.first_tx_mstamp);
+
+		/* Record send time of most recently ACKed packet: */
+		tp->first_tx_mstamp  = skb->skb_mstamp;
+	}
+	/* Mark off the skb delivered once it's sacked to avoid being
+	 * used again when it's cumulatively acked. For acked packets
+	 * we don't need to reset since it'll be freed soon.
+	 */
+	if (scb->sacked & TCPCB_SACKED_ACKED)
+		scb->tx.delivered_mstamp.v64 = 0;
+}
+
+/* Update the connection delivery information and generate a rate sample. */
+void tcp_rate_gen(struct sock *sk, u32 delivered, u32 lost,
+		  struct skb_mstamp *now, struct rate_sample *rs)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+	u32 snd_us, ack_us;
+
+	/* Clear app limited if bubble is acked and gone. */
+	if (tp->app_limited && after(tp->delivered, tp->app_limited))
+		tp->app_limited = 0;
+
+	/* TODO: there are multiple places throughout tcp_ack() to get
+	 * current time. Refactor the code using a new "tcp_acktag_state"
+	 * to carry current time, flags, stats like "tcp_sacktag_state".
+	 */
+	if (delivered)
+		tp->delivered_mstamp = *now;
+
+	rs->acked_sacked = delivered;	/* freshly ACKed or SACKed */
+	rs->losses = lost;		/* freshly marked lost */
+	/* Return an invalid sample if no timing information is available. */
+	if (!rs->prior_mstamp.v64) {
+		rs->delivered = -1;
+		rs->interval_us = -1;
+		return;
+	}
+	rs->delivered   = tp->delivered - rs->prior_delivered;
+
+	/* Model sending data and receiving ACKs as separate pipeline phases
+	 * for a window. Usually the ACK phase is longer, but with ACK
+	 * compression the send phase can be longer. To be safe we use the
+	 * longer phase.
+	 */
+	snd_us = rs->interval_us;				/* send phase */
+	ack_us = skb_mstamp_us_delta(now, &rs->prior_mstamp);	/* ack phase */
+	rs->interval_us = max(snd_us, ack_us);
+
+	/* Normally we expect interval_us >= min-rtt.
+	 * Note that rate may still be over-estimated when a spuriously
+	 * retransmistted skb was first (s)acked because "interval_us"
+	 * is under-estimated (up to an RTT). However continuously
+	 * measuring the delivery rate during loss recovery is crucial
+	 * for connections suffer heavy or prolonged losses.
+	 */
+	if (unlikely(rs->interval_us < tcp_min_rtt(tp))) {
+		if (!rs->is_retrans)
+			pr_debug("tcp rate: %ld %d %u %u %u\n",
+				 rs->interval_us, rs->delivered,
+				 inet_csk(sk)->icsk_ca_state,
+				 tp->rx_opt.sack_ok, tcp_min_rtt(tp));
+		rs->interval_us = -1;
+		return;
+	}
+
+	/* Record the last non-app-limited or the highest app-limited bw */
+	if (!rs->is_app_limited ||
+	    ((u64)rs->delivered * tp->rate_interval_us >=
+	     (u64)tp->rate_delivered * rs->interval_us)) {
+		tp->rate_delivered = rs->delivered;
+		tp->rate_interval_us = rs->interval_us;
+		tp->rate_app_limited = rs->is_app_limited;
+	}
+}
+
+/* If a gap is detected between sends, mark the socket application-limited. */
+void tcp_rate_check_app_limited(struct sock *sk)
+{
+	struct tcp_sock *tp = tcp_sk(sk);
+
+	if (/* We have less than one packet to send. */
+	    tp->write_seq - tp->snd_nxt < tp->mss_cache &&
+	    /* Nothing in sending host's qdisc queues or NIC tx queue. */
+	    sk_wmem_alloc_get(sk) < SKB_TRUESIZE(1) &&
+	    /* We are not limited by CWND. */
+	    tcp_packets_in_flight(tp) < tp->snd_cwnd &&
+	    /* All lost packets have been retransmitted. */
+	    tp->lost_out <= tp->retrans_out)
+		tp->app_limited =
+			(tp->delivered + tcp_packets_in_flight(tp)) ? : 1;
+}
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index d84930b2dd95..f712b411f6ed 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -384,6 +384,7 @@ static void tcp_fastopen_synack_timer(struct sock *sk)
 	 */
 	inet_rtx_syn_ack(sk, req);
 	req->num_timeout++;
+	icsk->icsk_retransmits++;
 	inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
 			  TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX);
 }
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c
index 028eb046ea40..9c5fc973267f 100644
--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -76,7 +76,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked)
 	if (!tcp_is_cwnd_limited(sk))
 		return;
 
-	if (tp->snd_cwnd <= tp->snd_ssthresh)
+	if (tcp_in_slow_start(tp))
 		tcp_slow_start(tp, acked);
 
 	else if (!yeah->doing_reno_now) {
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 058c31286ce1..7d96dc2d3d08 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1021,12 +1021,6 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 				   flow_flags,
 				   faddr, saddr, dport, inet->inet_sport);
 
-		if (!saddr && ipc.oif) {
-			err = l3mdev_get_saddr(net, ipc.oif, fl4);
-			if (err < 0)
-				goto out;
-		}
-
 		security_sk_classify_flow(sk, flowi4_to_flowi(fl4));
 		rt = ip_route_output_flow(net, fl4, sk);
 		if (IS_ERR(rt)) {
diff --git a/net/ipv4/udp_diag.c b/net/ipv4/udp_diag.c
index 8a9f6e535caa..9a89c10a55f0 100644
--- a/net/ipv4/udp_diag.c
+++ b/net/ipv4/udp_diag.c
@@ -20,7 +20,7 @@
 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 			struct netlink_callback *cb,
 			const struct inet_diag_req_v2 *req,
-			struct nlattr *bc)
+			struct nlattr *bc, bool net_admin)
 {
 	if (!inet_diag_bc_sk(bc, sk))
 		return 0;
@@ -28,7 +28,7 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
 	return inet_sk_diag_fill(sk, NULL, skb, req,
 			sk_user_ns(NETLINK_CB(cb->skb).sk),
 			NETLINK_CB(cb->skb).portid,
-			cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
+			cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
 }
 
 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
@@ -76,7 +76,8 @@ static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
 	err = inet_sk_diag_fill(sk, NULL, rep, req,
 			   sk_user_ns(NETLINK_CB(in_skb).sk),
 			   NETLINK_CB(in_skb).portid,
-			   nlh->nlmsg_seq, 0, nlh);
+			   nlh->nlmsg_seq, 0, nlh,
+			   netlink_net_capable(in_skb, CAP_NET_ADMIN));
 	if (err < 0) {
 		WARN_ON(err == -EMSGSIZE);
 		kfree_skb(rep);
@@ -97,6 +98,7 @@ static void udp_dump(struct udp_table *table, struct sk_buff *skb,
 		     struct netlink_callback *cb,
 		     const struct inet_diag_req_v2 *r, struct nlattr *bc)
 {
+	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 	struct net *net = sock_net(skb->sk);
 	int num, s_num, slot, s_slot;
 
@@ -132,7 +134,7 @@ static void udp_dump(struct udp_table *table, struct sk_buff *skb,
 			    r->id.idiag_dport)
 				goto next;
 
-			if (sk_diag_dump(sk, skb, cb, r, bc) < 0) {
+			if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
 				spin_unlock_bh(&hslot->lock);
 				goto done;
 			}
@@ -186,8 +188,8 @@ static int __udp_diag_destroy(struct sk_buff *in_skb,
 		if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
 		    ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
 			sk = __udp4_lib_lookup(net,
-					req->id.idiag_dst[0], req->id.idiag_dport,
-					req->id.idiag_src[0], req->id.idiag_sport,
+					req->id.idiag_dst[3], req->id.idiag_dport,
+					req->id.idiag_src[3], req->id.idiag_sport,
 					req->id.idiag_if, tbl, NULL);
 
 		else
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 81f253b6ff36..f9333c963607 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -21,7 +21,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 	__be16 new_protocol, bool is_ipv6)
 {
 	int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb);
-	bool remcsum, need_csum, offload_csum, ufo;
+	bool remcsum, need_csum, offload_csum, ufo, gso_partial;
 	struct sk_buff *segs = ERR_PTR(-EINVAL);
 	struct udphdr *uh = udp_hdr(skb);
 	u16 mac_offset = skb->mac_header;
@@ -88,6 +88,8 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 		goto out;
 	}
 
+	gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
+
 	outer_hlen = skb_tnl_header_len(skb);
 	udp_offset = outer_hlen - tnl_hlen;
 	skb = segs;
@@ -117,7 +119,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 		 * will be using a length value equal to only one MSS sized
 		 * segment instead of the entire frame.
 		 */
-		if (skb_is_gso(skb)) {
+		if (gso_partial) {
 			uh->len = htons(skb_shinfo(skb)->gso_size +
 					SKB_GSO_CB(skb)->data_offset +
 					skb->head - (unsigned char *)uh);
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index b644a23c3db0..6a7ff6957535 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -29,7 +29,7 @@ static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4,
 	memset(fl4, 0, sizeof(*fl4));
 	fl4->daddr = daddr->a4;
 	fl4->flowi4_tos = tos;
-	fl4->flowi4_oif = oif;
+	fl4->flowi4_oif = l3mdev_master_ifindex_by_index(net, oif);
 	if (saddr)
 		fl4->saddr = saddr->a4;
 
@@ -112,7 +112,7 @@ _decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
 	int oif = 0;
 
 	if (skb_dst(skb))
-		oif = l3mdev_fib_oif(skb_dst(skb)->dev);
+		oif = skb_dst(skb)->dev->ifindex;
 
 	memset(fl4, 0, sizeof(struct flowi4));
 	fl4->flowi4_mark = skb->mark;