diff --git a/include/net/netfilter/nf_nat_helper.h b/include/net/netfilter/nf_nat_helper.h
index efae84646353..44c421b9be85 100644
--- a/include/net/netfilter/nf_nat_helper.h
+++ b/include/net/netfilter/nf_nat_helper.h
@@ -38,4 +38,5 @@ bool nf_nat_mangle_udp_packet(struct sk_buff *skb, struct nf_conn *ct,
  * to port ct->master->saved_proto. */
 void nf_nat_follow_master(struct nf_conn *ct, struct nf_conntrack_expect *this);
 
+u16 nf_nat_exp_find_port(struct nf_conntrack_expect *exp, u16 port);
 #endif
diff --git a/include/uapi/linux/netfilter.h b/include/uapi/linux/netfilter.h
index 53411ccc69db..5a79ccb76701 100644
--- a/include/uapi/linux/netfilter.h
+++ b/include/uapi/linux/netfilter.h
@@ -63,7 +63,9 @@ enum {
 	NFPROTO_NETDEV =  5,
 	NFPROTO_BRIDGE =  7,
 	NFPROTO_IPV6   = 10,
+#ifndef __KERNEL__ /* no longer supported by kernel */
 	NFPROTO_DECNET = 12,
+#endif
 	NFPROTO_NUMPROTO,
 };
 
diff --git a/net/ipv4/netfilter/nf_nat_h323.c b/net/ipv4/netfilter/nf_nat_h323.c
index a334f0dcc2d0..faee20af4856 100644
--- a/net/ipv4/netfilter/nf_nat_h323.c
+++ b/net/ipv4/netfilter/nf_nat_h323.c
@@ -291,20 +291,7 @@ static int nat_t120(struct sk_buff *skb, struct nf_conn *ct,
 	exp->expectfn = nf_nat_follow_master;
 	exp->dir = !dir;
 
-	/* Try to get same port: if not, try to change it. */
-	for (; nated_port != 0; nated_port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(nated_port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			nated_port = 0;
-			break;
-		}
-	}
-
+	nated_port = nf_nat_exp_find_port(exp, nated_port);
 	if (nated_port == 0) {	/* No port available */
 		net_notice_ratelimited("nf_nat_h323: out of TCP ports\n");
 		return 0;
@@ -347,20 +334,7 @@ static int nat_h245(struct sk_buff *skb, struct nf_conn *ct,
 	if (info->sig_port[dir] == port)
 		nated_port = ntohs(info->sig_port[!dir]);
 
-	/* Try to get same port: if not, try to change it. */
-	for (; nated_port != 0; nated_port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(nated_port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			nated_port = 0;
-			break;
-		}
-	}
-
+	nated_port = nf_nat_exp_find_port(exp, nated_port);
 	if (nated_port == 0) {	/* No port available */
 		net_notice_ratelimited("nf_nat_q931: out of TCP ports\n");
 		return 0;
@@ -439,20 +413,7 @@ static int nat_q931(struct sk_buff *skb, struct nf_conn *ct,
 	if (info->sig_port[dir] == port)
 		nated_port = ntohs(info->sig_port[!dir]);
 
-	/* Try to get same port: if not, try to change it. */
-	for (; nated_port != 0; nated_port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(nated_port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			nated_port = 0;
-			break;
-		}
-	}
-
+	nated_port = nf_nat_exp_find_port(exp, nated_port);
 	if (nated_port == 0) {	/* No port available */
 		net_notice_ratelimited("nf_nat_ras: out of TCP ports\n");
 		return 0;
@@ -532,20 +493,7 @@ static int nat_callforwarding(struct sk_buff *skb, struct nf_conn *ct,
 	exp->expectfn = ip_nat_callforwarding_expect;
 	exp->dir = !dir;
 
-	/* Try to get same port: if not, try to change it. */
-	for (nated_port = ntohs(port); nated_port != 0; nated_port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(nated_port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			nated_port = 0;
-			break;
-		}
-	}
-
+	nated_port = nf_nat_exp_find_port(exp, ntohs(port));
 	if (nated_port == 0) {	/* No port available */
 		net_notice_ratelimited("nf_nat_q931: out of TCP ports\n");
 		return 0;
diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index 6b31746f9be3..e7ba5b6dd2b7 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -353,7 +353,7 @@ ip_set_init_comment(struct ip_set *set, struct ip_set_comment *comment,
 	c = kmalloc(sizeof(*c) + len + 1, GFP_ATOMIC);
 	if (unlikely(!c))
 		return;
-	strlcpy(c->str, ext->comment, len + 1);
+	strscpy(c->str, ext->comment, len + 1);
 	set->ext_size += sizeof(*c) + strlen(c->str) + 1;
 	rcu_assign_pointer(comment->c, c);
 }
@@ -1072,7 +1072,7 @@ static int ip_set_create(struct sk_buff *skb, const struct nfnl_info *info,
 	if (!set)
 		return -ENOMEM;
 	spin_lock_init(&set->lock);
-	strlcpy(set->name, name, IPSET_MAXNAMELEN);
+	strscpy(set->name, name, IPSET_MAXNAMELEN);
 	set->family = family;
 	set->revision = revision;
 
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 818b0b058b10..988222fff9f0 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -2611,7 +2611,7 @@ ip_vs_copy_service(struct ip_vs_service_entry *dst, struct ip_vs_service *src)
 	dst->addr = src->addr.ip;
 	dst->port = src->port;
 	dst->fwmark = src->fwmark;
-	strlcpy(dst->sched_name, sched_name, sizeof(dst->sched_name));
+	strscpy(dst->sched_name, sched_name, sizeof(dst->sched_name));
 	dst->flags = src->flags;
 	dst->timeout = src->timeout / HZ;
 	dst->netmask = src->netmask;
@@ -2805,13 +2805,13 @@ do_ip_vs_get_ctl(struct sock *sk, int cmd, void __user *user, int *len)
 		mutex_lock(&ipvs->sync_mutex);
 		if (ipvs->sync_state & IP_VS_STATE_MASTER) {
 			d[0].state = IP_VS_STATE_MASTER;
-			strlcpy(d[0].mcast_ifn, ipvs->mcfg.mcast_ifn,
+			strscpy(d[0].mcast_ifn, ipvs->mcfg.mcast_ifn,
 				sizeof(d[0].mcast_ifn));
 			d[0].syncid = ipvs->mcfg.syncid;
 		}
 		if (ipvs->sync_state & IP_VS_STATE_BACKUP) {
 			d[1].state = IP_VS_STATE_BACKUP;
-			strlcpy(d[1].mcast_ifn, ipvs->bcfg.mcast_ifn,
+			strscpy(d[1].mcast_ifn, ipvs->bcfg.mcast_ifn,
 				sizeof(d[1].mcast_ifn));
 			d[1].syncid = ipvs->bcfg.syncid;
 		}
@@ -3561,7 +3561,7 @@ static int ip_vs_genl_new_daemon(struct netns_ipvs *ipvs, struct nlattr **attrs)
 	      attrs[IPVS_DAEMON_ATTR_MCAST_IFN] &&
 	      attrs[IPVS_DAEMON_ATTR_SYNC_ID]))
 		return -EINVAL;
-	strlcpy(c.mcast_ifn, nla_data(attrs[IPVS_DAEMON_ATTR_MCAST_IFN]),
+	strscpy(c.mcast_ifn, nla_data(attrs[IPVS_DAEMON_ATTR_MCAST_IFN]),
 		sizeof(c.mcast_ifn));
 	c.syncid = nla_get_u32(attrs[IPVS_DAEMON_ATTR_SYNC_ID]);
 
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index a634c72b1ffc..656631083177 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -47,6 +47,12 @@ static const char *const tcp_conntrack_names[] = {
 	"SYN_SENT2",
 };
 
+enum nf_ct_tcp_action {
+	NFCT_TCP_IGNORE,
+	NFCT_TCP_INVALID,
+	NFCT_TCP_ACCEPT,
+};
+
 #define SECS * HZ
 #define MINS * 60 SECS
 #define HOURS * 60 MINS
@@ -472,23 +478,45 @@ static void tcp_init_sender(struct ip_ct_tcp_state *sender,
 	}
 }
 
-static bool tcp_in_window(struct nf_conn *ct,
-			  enum ip_conntrack_dir dir,
-			  unsigned int index,
-			  const struct sk_buff *skb,
-			  unsigned int dataoff,
-			  const struct tcphdr *tcph,
-			  const struct nf_hook_state *hook_state)
+__printf(6, 7)
+static enum nf_ct_tcp_action nf_tcp_log_invalid(const struct sk_buff *skb,
+						const struct nf_conn *ct,
+						const struct nf_hook_state *state,
+						const struct ip_ct_tcp_state *sender,
+						enum nf_ct_tcp_action ret,
+						const char *fmt, ...)
+{
+	const struct nf_tcp_net *tn = nf_tcp_pernet(nf_ct_net(ct));
+	struct va_format vaf;
+	va_list args;
+	bool be_liberal;
+
+	be_liberal = sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL || tn->tcp_be_liberal;
+	if (be_liberal)
+		return NFCT_TCP_ACCEPT;
+
+	va_start(args, fmt);
+	vaf.fmt = fmt;
+	vaf.va = &args;
+	nf_ct_l4proto_log_invalid(skb, ct, state, "%pV", &vaf);
+	va_end(args);
+
+	return ret;
+}
+
+static enum nf_ct_tcp_action
+tcp_in_window(struct nf_conn *ct, enum ip_conntrack_dir dir,
+	      unsigned int index, const struct sk_buff *skb,
+	      unsigned int dataoff, const struct tcphdr *tcph,
+	      const struct nf_hook_state *hook_state)
 {
 	struct ip_ct_tcp *state = &ct->proto.tcp;
-	struct net *net = nf_ct_net(ct);
-	struct nf_tcp_net *tn = nf_tcp_pernet(net);
 	struct ip_ct_tcp_state *sender = &state->seen[dir];
 	struct ip_ct_tcp_state *receiver = &state->seen[!dir];
 	__u32 seq, ack, sack, end, win, swin;
-	u16 win_raw;
+	bool in_recv_win, seq_ok;
 	s32 receiver_offset;
-	bool res, in_recv_win;
+	u16 win_raw;
 
 	/*
 	 * Get the required data from the packet.
@@ -517,7 +545,7 @@ static bool tcp_in_window(struct nf_conn *ct,
 					end, win);
 			if (!tcph->ack)
 				/* Simultaneous open */
-				return true;
+				return NFCT_TCP_ACCEPT;
 		} else {
 			/*
 			 * We are in the middle of a connection,
@@ -560,7 +588,7 @@ static bool tcp_in_window(struct nf_conn *ct,
 				end, win);
 
 		if (dir == IP_CT_DIR_REPLY && !tcph->ack)
-			return true;
+			return NFCT_TCP_ACCEPT;
 	}
 
 	if (!(tcph->ack)) {
@@ -584,122 +612,166 @@ static bool tcp_in_window(struct nf_conn *ct,
 		 */
 		seq = end = sender->td_end;
 
+	seq_ok = before(seq, sender->td_maxend + 1);
+	if (!seq_ok) {
+		u32 overshot = end - sender->td_maxend + 1;
+		bool ack_ok;
+
+		ack_ok = after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1);
+		in_recv_win = receiver->td_maxwin &&
+			      after(end, sender->td_end - receiver->td_maxwin - 1);
+
+		if (in_recv_win &&
+		    ack_ok &&
+		    overshot <= receiver->td_maxwin &&
+		    before(sack, receiver->td_end + 1)) {
+			/* Work around TCPs that send more bytes than allowed by
+			 * the receive window.
+			 *
+			 * If the (marked as invalid) packet is allowed to pass by
+			 * the ruleset and the peer acks this data, then its possible
+			 * all future packets will trigger 'ACK is over upper bound' check.
+			 *
+			 * Thus if only the sequence check fails then do update td_end so
+			 * possible ACK for this data can update internal state.
+			 */
+			sender->td_end = end;
+			sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
+
+			return nf_tcp_log_invalid(skb, ct, hook_state, sender, NFCT_TCP_IGNORE,
+						  "%u bytes more than expected", overshot);
+		}
+
+		return nf_tcp_log_invalid(skb, ct, hook_state, sender, NFCT_TCP_INVALID,
+					  "SEQ is over upper bound %u (over the window of the receiver)",
+					  sender->td_maxend + 1);
+	}
+
+	if (!before(sack, receiver->td_end + 1))
+		return nf_tcp_log_invalid(skb, ct, hook_state, sender, NFCT_TCP_INVALID,
+					  "ACK is over upper bound %u (ACKed data not seen yet)",
+					  receiver->td_end + 1);
+
 	/* Is the ending sequence in the receive window (if available)? */
 	in_recv_win = !receiver->td_maxwin ||
 		      after(end, sender->td_end - receiver->td_maxwin - 1);
+	if (!in_recv_win)
+		return nf_tcp_log_invalid(skb, ct, hook_state, sender, NFCT_TCP_IGNORE,
+					  "SEQ is under lower bound %u (already ACKed data retransmitted)",
+					  sender->td_end - receiver->td_maxwin - 1);
+	if (!after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1))
+		return nf_tcp_log_invalid(skb, ct, hook_state, sender, NFCT_TCP_IGNORE,
+					  "ignored ACK under lower bound %u (possible overly delayed)",
+					  receiver->td_end - MAXACKWINDOW(sender) - 1);
 
-	if (before(seq, sender->td_maxend + 1) &&
-	    in_recv_win &&
-	    before(sack, receiver->td_end + 1) &&
-	    after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1)) {
-		/*
-		 * Take into account window scaling (RFC 1323).
-		 */
-		if (!tcph->syn)
-			win <<= sender->td_scale;
+	/* Take into account window scaling (RFC 1323). */
+	if (!tcph->syn)
+		win <<= sender->td_scale;
 
-		/*
-		 * Update sender data.
-		 */
-		swin = win + (sack - ack);
-		if (sender->td_maxwin < swin)
-			sender->td_maxwin = swin;
-		if (after(end, sender->td_end)) {
-			sender->td_end = end;
-			sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
-		}
-		if (tcph->ack) {
-			if (!(sender->flags & IP_CT_TCP_FLAG_MAXACK_SET)) {
-				sender->td_maxack = ack;
-				sender->flags |= IP_CT_TCP_FLAG_MAXACK_SET;
-			} else if (after(ack, sender->td_maxack))
-				sender->td_maxack = ack;
-		}
-
-		/*
-		 * Update receiver data.
-		 */
-		if (receiver->td_maxwin != 0 && after(end, sender->td_maxend))
-			receiver->td_maxwin += end - sender->td_maxend;
-		if (after(sack + win, receiver->td_maxend - 1)) {
-			receiver->td_maxend = sack + win;
-			if (win == 0)
-				receiver->td_maxend++;
-		}
-		if (ack == receiver->td_end)
-			receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
-
-		/*
-		 * Check retransmissions.
-		 */
-		if (index == TCP_ACK_SET) {
-			if (state->last_dir == dir
-			    && state->last_seq == seq
-			    && state->last_ack == ack
-			    && state->last_end == end
-			    && state->last_win == win_raw)
-				state->retrans++;
-			else {
-				state->last_dir = dir;
-				state->last_seq = seq;
-				state->last_ack = ack;
-				state->last_end = end;
-				state->last_win = win_raw;
-				state->retrans = 0;
-			}
-		}
-		res = true;
-	} else {
-		res = false;
-		if (sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL ||
-		    tn->tcp_be_liberal)
-			res = true;
-		if (!res) {
-			bool seq_ok = before(seq, sender->td_maxend + 1);
-
-			if (!seq_ok) {
-				u32 overshot = end - sender->td_maxend + 1;
-				bool ack_ok;
-
-				ack_ok = after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1);
-
-				if (in_recv_win &&
-				    ack_ok &&
-				    overshot <= receiver->td_maxwin &&
-				    before(sack, receiver->td_end + 1)) {
-					/* Work around TCPs that send more bytes than allowed by
-					 * the receive window.
-					 *
-					 * If the (marked as invalid) packet is allowed to pass by
-					 * the ruleset and the peer acks this data, then its possible
-					 * all future packets will trigger 'ACK is over upper bound' check.
-					 *
-					 * Thus if only the sequence check fails then do update td_end so
-					 * possible ACK for this data can update internal state.
-					 */
-					sender->td_end = end;
-					sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
-
-					nf_ct_l4proto_log_invalid(skb, ct, hook_state,
-								  "%u bytes more than expected", overshot);
-					return res;
-				}
-			}
-
-			nf_ct_l4proto_log_invalid(skb, ct, hook_state,
-			"%s",
-			before(seq, sender->td_maxend + 1) ?
-			in_recv_win ?
-			before(sack, receiver->td_end + 1) ?
-			after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1) ? "BUG"
-			: "ACK is under the lower bound (possible overly delayed ACK)"
-			: "ACK is over the upper bound (ACKed data not seen yet)"
-			: "SEQ is under the lower bound (already ACKed data retransmitted)"
-			: "SEQ is over the upper bound (over the window of the receiver)");
+	/* Update sender data. */
+	swin = win + (sack - ack);
+	if (sender->td_maxwin < swin)
+		sender->td_maxwin = swin;
+	if (after(end, sender->td_end)) {
+		sender->td_end = end;
+		sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
+	}
+	if (tcph->ack) {
+		if (!(sender->flags & IP_CT_TCP_FLAG_MAXACK_SET)) {
+			sender->td_maxack = ack;
+			sender->flags |= IP_CT_TCP_FLAG_MAXACK_SET;
+		} else if (after(ack, sender->td_maxack)) {
+			sender->td_maxack = ack;
 		}
 	}
 
-	return res;
+	/* Update receiver data. */
+	if (receiver->td_maxwin != 0 && after(end, sender->td_maxend))
+		receiver->td_maxwin += end - sender->td_maxend;
+	if (after(sack + win, receiver->td_maxend - 1)) {
+		receiver->td_maxend = sack + win;
+		if (win == 0)
+			receiver->td_maxend++;
+	}
+	if (ack == receiver->td_end)
+		receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
+
+	/* Check retransmissions. */
+	if (index == TCP_ACK_SET) {
+		if (state->last_dir == dir &&
+		    state->last_seq == seq &&
+		    state->last_ack == ack &&
+		    state->last_end == end &&
+		    state->last_win == win_raw) {
+			state->retrans++;
+		} else {
+			state->last_dir = dir;
+			state->last_seq = seq;
+			state->last_ack = ack;
+			state->last_end = end;
+			state->last_win = win_raw;
+			state->retrans = 0;
+		}
+	}
+
+	return NFCT_TCP_ACCEPT;
+}
+
+static void __cold nf_tcp_handle_invalid(struct nf_conn *ct,
+					 enum ip_conntrack_dir dir,
+					 int index,
+					 const struct sk_buff *skb,
+					 const struct nf_hook_state *hook_state)
+{
+	const unsigned int *timeouts;
+	const struct nf_tcp_net *tn;
+	unsigned int timeout;
+	u32 expires;
+
+	if (!test_bit(IPS_ASSURED_BIT, &ct->status) ||
+	    test_bit(IPS_FIXED_TIMEOUT_BIT, &ct->status))
+		return;
+
+	/* We don't want to have connections hanging around in ESTABLISHED
+	 * state for long time 'just because' conntrack deemed a FIN/RST
+	 * out-of-window.
+	 *
+	 * Shrink the timeout just like when there is unacked data.
+	 * This speeds up eviction of 'dead' connections where the
+	 * connection and conntracks internal state are out of sync.
+	 */
+	switch (index) {
+	case TCP_RST_SET:
+	case TCP_FIN_SET:
+		break;
+	default:
+		return;
+	}
+
+	if (ct->proto.tcp.last_dir != dir &&
+	    (ct->proto.tcp.last_index == TCP_FIN_SET ||
+	     ct->proto.tcp.last_index == TCP_RST_SET)) {
+		expires = nf_ct_expires(ct);
+		if (expires < 120 * HZ)
+			return;
+
+		tn = nf_tcp_pernet(nf_ct_net(ct));
+		timeouts = nf_ct_timeout_lookup(ct);
+		if (!timeouts)
+			timeouts = tn->timeouts;
+
+		timeout = READ_ONCE(timeouts[TCP_CONNTRACK_UNACK]);
+		if (expires > timeout) {
+			nf_ct_l4proto_log_invalid(skb, ct, hook_state,
+					  "packet (index %d, dir %d) response for index %d lower timeout to %u",
+					  index, dir, ct->proto.tcp.last_index, timeout);
+
+			WRITE_ONCE(ct->timeout, timeout + nfct_time_stamp);
+		}
+	} else {
+		ct->proto.tcp.last_index = index;
+		ct->proto.tcp.last_dir = dir;
+	}
 }
 
 /* table of valid flag combinations - PUSH, ECE and CWR are always valid */
@@ -861,6 +933,7 @@ int nf_conntrack_tcp_packet(struct nf_conn *ct,
 	struct nf_conntrack_tuple *tuple;
 	enum tcp_conntrack new_state, old_state;
 	unsigned int index, *timeouts;
+	enum nf_ct_tcp_action res;
 	enum ip_conntrack_dir dir;
 	const struct tcphdr *th;
 	struct tcphdr _tcph;
@@ -1126,10 +1199,18 @@ int nf_conntrack_tcp_packet(struct nf_conn *ct,
 		break;
 	}
 
-	if (!tcp_in_window(ct, dir, index,
-			   skb, dataoff, th, state)) {
+	res = tcp_in_window(ct, dir, index,
+			    skb, dataoff, th, state);
+	switch (res) {
+	case NFCT_TCP_IGNORE:
+		spin_unlock_bh(&ct->lock);
+		return NF_ACCEPT;
+	case NFCT_TCP_INVALID:
+		nf_tcp_handle_invalid(ct, dir, index, skb, state);
 		spin_unlock_bh(&ct->lock);
 		return -NF_ACCEPT;
+	case NFCT_TCP_ACCEPT:
+		break;
 	}
      in_window:
 	/* From now on we have got in-window packets */
diff --git a/net/netfilter/nf_log.c b/net/netfilter/nf_log.c
index edee7fa944c1..8a29290149bd 100644
--- a/net/netfilter/nf_log.c
+++ b/net/netfilter/nf_log.c
@@ -443,9 +443,9 @@ static int nf_log_proc_dostring(struct ctl_table *table, int write,
 		mutex_lock(&nf_log_mutex);
 		logger = nft_log_dereference(net->nf.nf_loggers[tindex]);
 		if (!logger)
-			strlcpy(buf, "NONE", sizeof(buf));
+			strscpy(buf, "NONE", sizeof(buf));
 		else
-			strlcpy(buf, logger->name, sizeof(buf));
+			strscpy(buf, logger->name, sizeof(buf));
 		mutex_unlock(&nf_log_mutex);
 		r = proc_dostring(&tmp, write, buffer, lenp, ppos);
 	}
diff --git a/net/netfilter/nf_nat_amanda.c b/net/netfilter/nf_nat_amanda.c
index 3bc7e0854efe..98deef6cde69 100644
--- a/net/netfilter/nf_nat_amanda.c
+++ b/net/netfilter/nf_nat_amanda.c
@@ -44,19 +44,7 @@ static unsigned int help(struct sk_buff *skb,
 	exp->expectfn = nf_nat_follow_master;
 
 	/* Try to get same port: if not, try to change it. */
-	for (port = ntohs(exp->saved_proto.tcp.port); port != 0; port++) {
-		int res;
-
-		exp->tuple.dst.u.tcp.port = htons(port);
-		res = nf_ct_expect_related(exp, 0);
-		if (res == 0)
-			break;
-		else if (res != -EBUSY) {
-			port = 0;
-			break;
-		}
-	}
-
+	port = nf_nat_exp_find_port(exp, ntohs(exp->saved_proto.tcp.port));
 	if (port == 0) {
 		nf_ct_helper_log(skb, exp->master, "all ports in use");
 		return NF_DROP;
diff --git a/net/netfilter/nf_nat_ftp.c b/net/netfilter/nf_nat_ftp.c
index aace6768a64e..c92a436d9c48 100644
--- a/net/netfilter/nf_nat_ftp.c
+++ b/net/netfilter/nf_nat_ftp.c
@@ -86,22 +86,9 @@ static unsigned int nf_nat_ftp(struct sk_buff *skb,
 	 * this one. */
 	exp->expectfn = nf_nat_follow_master;
 
-	/* Try to get same port: if not, try to change it. */
-	for (port = ntohs(exp->saved_proto.tcp.port); port != 0; port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			port = 0;
-			break;
-		}
-	}
-
+	port = nf_nat_exp_find_port(exp, ntohs(exp->saved_proto.tcp.port));
 	if (port == 0) {
-		nf_ct_helper_log(skb, ct, "all ports in use");
+		nf_ct_helper_log(skb, exp->master, "all ports in use");
 		return NF_DROP;
 	}
 
diff --git a/net/netfilter/nf_nat_helper.c b/net/netfilter/nf_nat_helper.c
index a263505455fc..a95a25196943 100644
--- a/net/netfilter/nf_nat_helper.c
+++ b/net/netfilter/nf_nat_helper.c
@@ -198,3 +198,34 @@ void nf_nat_follow_master(struct nf_conn *ct,
 	nf_nat_setup_info(ct, &range, NF_NAT_MANIP_DST);
 }
 EXPORT_SYMBOL(nf_nat_follow_master);
+
+u16 nf_nat_exp_find_port(struct nf_conntrack_expect *exp, u16 port)
+{
+	static const unsigned int max_attempts = 128;
+	int range, attempts_left;
+	u16 min = port;
+
+	range = USHRT_MAX - port;
+	attempts_left = range;
+
+	if (attempts_left > max_attempts)
+		attempts_left = max_attempts;
+
+	/* Try to get same port: if not, try to change it. */
+	for (;;) {
+		int res;
+
+		exp->tuple.dst.u.tcp.port = htons(port);
+		res = nf_ct_expect_related(exp, 0);
+		if (res == 0)
+			return port;
+
+		if (res != -EBUSY || (--attempts_left < 0))
+			break;
+
+		port = min + prandom_u32_max(range);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nf_nat_exp_find_port);
diff --git a/net/netfilter/nf_nat_irc.c b/net/netfilter/nf_nat_irc.c
index c691ab8d234c..19c4fcc60c50 100644
--- a/net/netfilter/nf_nat_irc.c
+++ b/net/netfilter/nf_nat_irc.c
@@ -48,20 +48,8 @@ static unsigned int help(struct sk_buff *skb,
 	exp->dir = IP_CT_DIR_REPLY;
 	exp->expectfn = nf_nat_follow_master;
 
-	/* Try to get same port: if not, try to change it. */
-	for (port = ntohs(exp->saved_proto.tcp.port); port != 0; port++) {
-		int ret;
-
-		exp->tuple.dst.u.tcp.port = htons(port);
-		ret = nf_ct_expect_related(exp, 0);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			port = 0;
-			break;
-		}
-	}
-
+	port = nf_nat_exp_find_port(exp,
+				    ntohs(exp->saved_proto.tcp.port));
 	if (port == 0) {
 		nf_ct_helper_log(skb, ct, "all ports in use");
 		return NF_DROP;
diff --git a/net/netfilter/nf_nat_sip.c b/net/netfilter/nf_nat_sip.c
index f0a735e86851..cf4aeb299bde 100644
--- a/net/netfilter/nf_nat_sip.c
+++ b/net/netfilter/nf_nat_sip.c
@@ -410,19 +410,7 @@ static unsigned int nf_nat_sip_expect(struct sk_buff *skb, unsigned int protoff,
 	exp->dir = !dir;
 	exp->expectfn = nf_nat_sip_expected;
 
-	for (; port != 0; port++) {
-		int ret;
-
-		exp->tuple.dst.u.udp.port = htons(port);
-		ret = nf_ct_expect_related(exp, NF_CT_EXP_F_SKIP_MASTER);
-		if (ret == 0)
-			break;
-		else if (ret != -EBUSY) {
-			port = 0;
-			break;
-		}
-	}
-
+	port = nf_nat_exp_find_port(exp, port);
 	if (port == 0) {
 		nf_ct_helper_log(skb, ct, "all ports in use for SIP");
 		return NF_DROP;
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 816052089b33..4de0a30d2009 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -742,7 +742,7 @@ __printf(2, 3) int nft_request_module(struct net *net, const char *fmt,
 		return -ENOMEM;
 
 	req->done = false;
-	strlcpy(req->module, module_name, MODULE_NAME_LEN);
+	strscpy(req->module, module_name, MODULE_NAME_LEN);
 	list_add_tail(&req->list, &nft_net->module_list);
 
 	return -EAGAIN;
diff --git a/net/netfilter/nft_osf.c b/net/netfilter/nft_osf.c
index 89342ccccdcc..adacf95b6e2b 100644
--- a/net/netfilter/nft_osf.c
+++ b/net/netfilter/nft_osf.c
@@ -51,7 +51,7 @@ static void nft_osf_eval(const struct nft_expr *expr, struct nft_regs *regs,
 			snprintf(os_match, NFT_OSF_MAXGENRELEN, "%s:%s",
 				 data.genre, data.version);
 		else
-			strlcpy(os_match, data.genre, NFT_OSF_MAXGENRELEN);
+			strscpy(os_match, data.genre, NFT_OSF_MAXGENRELEN);
 
 		strncpy((char *)dest, os_match, NFT_OSF_MAXGENRELEN);
 	}
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index 54a489f16b17..470282cf3fae 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -766,7 +766,7 @@ void xt_compat_match_from_user(struct xt_entry_match *m, void **dstptr,
 
 	msize += off;
 	m->u.user.match_size = msize;
-	strlcpy(name, match->name, sizeof(name));
+	strscpy(name, match->name, sizeof(name));
 	module_put(match->me);
 	strncpy(m->u.user.name, name, sizeof(m->u.user.name));
 
@@ -1146,7 +1146,7 @@ void xt_compat_target_from_user(struct xt_entry_target *t, void **dstptr,
 
 	tsize += off;
 	t->u.user.target_size = tsize;
-	strlcpy(name, target->name, sizeof(name));
+	strscpy(name, target->name, sizeof(name));
 	module_put(target->me);
 	strncpy(t->u.user.name, name, sizeof(t->u.user.name));
 
@@ -1827,7 +1827,7 @@ int xt_proto_init(struct net *net, u_int8_t af)
 	root_uid = make_kuid(net->user_ns, 0);
 	root_gid = make_kgid(net->user_ns, 0);
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_TABLES, sizeof(buf));
 	proc = proc_create_net_data(buf, 0440, net->proc_net, &xt_table_seq_ops,
 			sizeof(struct seq_net_private),
@@ -1837,7 +1837,7 @@ int xt_proto_init(struct net *net, u_int8_t af)
 	if (uid_valid(root_uid) && gid_valid(root_gid))
 		proc_set_user(proc, root_uid, root_gid);
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_MATCHES, sizeof(buf));
 	proc = proc_create_seq_private(buf, 0440, net->proc_net,
 			&xt_match_seq_ops, sizeof(struct nf_mttg_trav),
@@ -1847,7 +1847,7 @@ int xt_proto_init(struct net *net, u_int8_t af)
 	if (uid_valid(root_uid) && gid_valid(root_gid))
 		proc_set_user(proc, root_uid, root_gid);
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_TARGETS, sizeof(buf));
 	proc = proc_create_seq_private(buf, 0440, net->proc_net,
 			 &xt_target_seq_ops, sizeof(struct nf_mttg_trav),
@@ -1862,12 +1862,12 @@ int xt_proto_init(struct net *net, u_int8_t af)
 
 #ifdef CONFIG_PROC_FS
 out_remove_matches:
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_MATCHES, sizeof(buf));
 	remove_proc_entry(buf, net->proc_net);
 
 out_remove_tables:
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_TABLES, sizeof(buf));
 	remove_proc_entry(buf, net->proc_net);
 out:
@@ -1881,15 +1881,15 @@ void xt_proto_fini(struct net *net, u_int8_t af)
 #ifdef CONFIG_PROC_FS
 	char buf[XT_FUNCTION_MAXNAMELEN];
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_TABLES, sizeof(buf));
 	remove_proc_entry(buf, net->proc_net);
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_TARGETS, sizeof(buf));
 	remove_proc_entry(buf, net->proc_net);
 
-	strlcpy(buf, xt_prefix[af], sizeof(buf));
+	strscpy(buf, xt_prefix[af], sizeof(buf));
 	strlcat(buf, FORMAT_MATCHES, sizeof(buf));
 	remove_proc_entry(buf, net->proc_net);
 #endif /*CONFIG_PROC_FS*/
diff --git a/net/netfilter/xt_RATEEST.c b/net/netfilter/xt_RATEEST.c
index 8aec1b529364..80f6624e2355 100644
--- a/net/netfilter/xt_RATEEST.c
+++ b/net/netfilter/xt_RATEEST.c
@@ -144,7 +144,7 @@ static int xt_rateest_tg_checkentry(const struct xt_tgchk_param *par)
 		goto err1;
 
 	gnet_stats_basic_sync_init(&est->bstats);
-	strlcpy(est->name, info->name, sizeof(est->name));
+	strscpy(est->name, info->name, sizeof(est->name));
 	spin_lock_init(&est->lock);
 	est->refcnt		= 1;
 	est->params.interval	= info->interval;