4 files changed, 46 insertions, 20 deletions

diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index d6ee343fdb86..aa0b22697998 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -515,6 +515,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
 	struct rb_node *rbn;
 	int len;
 	int ihlen;
+	int delta;
 	int err;
 	u8 ecn;
 
@@ -556,10 +557,16 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
 	if (len > 65535)
 		goto out_oversize;
 
+	delta = - head->truesize;
+
 	/* Head of list must not be cloned. */
 	if (skb_unclone(head, GFP_ATOMIC))
 		goto out_nomem;
 
+	delta += head->truesize;
+	if (delta)
+		add_frag_mem_limit(qp->q.net, delta);
+
 	/* If the first fragment is fragmented itself, we split
 	 * it to two chunks: the first with data and paged part
 	 * and the second, holding only fragments. */
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 72250b4e466d..26921f6b3b92 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -546,7 +546,7 @@ static void ip_list_rcv_finish(struct net *net, struct sock *sk,
 	list_for_each_entry_safe(skb, next, head, list) {
 		struct dst_entry *dst;
 
-		list_del(&skb->list);
+		skb_list_del_init(skb);
 		/* if ingress device is enslaved to an L3 master device pass the
 		 * skb to its handler for processing
 		 */
@@ -593,7 +593,7 @@ void ip_list_rcv(struct list_head *head, struct packet_type *pt,
 		struct net_device *dev = skb->dev;
 		struct net *net = dev_net(dev);
 
-		list_del(&skb->list);
+		skb_list_del_init(skb);
 		skb = ip_rcv_core(skb, net);
 		if (skb == NULL)
 			continue;
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d3b691f3a9e8..c31badfee806 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1904,7 +1904,9 @@ static int tso_fragment(struct sock *sk, enum tcp_queue tcp_queue,
  * This algorithm is from John Heffner.
  */
 static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
-				 bool *is_cwnd_limited, u32 max_segs)
+				 bool *is_cwnd_limited,
+				 bool *is_rwnd_limited,
+				 u32 max_segs)
 {
 	const struct inet_connection_sock *icsk = inet_csk(sk);
 	u32 send_win, cong_win, limit, in_flight;
@@ -1913,9 +1915,6 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
 	int win_divisor;
 	s64 delta;
 
-	if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
-		goto send_now;
-
 	if (icsk->icsk_ca_state >= TCP_CA_Recovery)
 		goto send_now;
 
@@ -1981,10 +1980,27 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
 	if ((s64)(delta - (u64)NSEC_PER_USEC * (tp->srtt_us >> 4)) < 0)
 		goto send_now;
 
-	/* Ok, it looks like it is advisable to defer. */
+	/* Ok, it looks like it is advisable to defer.
+	 * Three cases are tracked :
+	 * 1) We are cwnd-limited
+	 * 2) We are rwnd-limited
+	 * 3) We are application limited.
+	 */
+	if (cong_win < send_win) {
+		if (cong_win <= skb->len) {
+			*is_cwnd_limited = true;
+			return true;
+		}
+	} else {
+		if (send_win <= skb->len) {
+			*is_rwnd_limited = true;
+			return true;
+		}
+	}
 
-	if (cong_win < send_win && cong_win <= skb->len)
-		*is_cwnd_limited = true;
+	/* If this packet won't get more data, do not wait. */
+	if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
+		goto send_now;
 
 	return true;
 
@@ -2365,7 +2381,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle,
 		} else {
 			if (!push_one &&
 			    tcp_tso_should_defer(sk, skb, &is_cwnd_limited,
-						 max_segs))
+						 &is_rwnd_limited, max_segs))
 				break;
 		}
 
@@ -2503,15 +2519,18 @@ void tcp_send_loss_probe(struct sock *sk)
 		goto rearm_timer;
 	}
 	skb = skb_rb_last(&sk->tcp_rtx_queue);
+	if (unlikely(!skb)) {
+		WARN_ONCE(tp->packets_out,
+			  "invalid inflight: %u state %u cwnd %u mss %d\n",
+			  tp->packets_out, sk->sk_state, tp->snd_cwnd, mss);
+		inet_csk(sk)->icsk_pending = 0;
+		return;
+	}
 
 	/* At most one outstanding TLP retransmission. */
 	if (tp->tlp_high_seq)
 		goto rearm_timer;
 
-	/* Retransmit last segment. */
-	if (WARN_ON(!skb))
-		goto rearm_timer;
-
 	if (skb_still_in_host_queue(sk, skb))
 		goto rearm_timer;
 
@@ -2929,7 +2948,7 @@ int __tcp_retransmit_skb(struct sock *sk, struct sk_buff *skb, int segs)
 		TCP_SKB_CB(skb)->sacked |= TCPCB_EVER_RETRANS;
 		trace_tcp_retransmit_skb(sk, skb);
 	} else if (err != -EBUSY) {
-		NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL);
+		NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPRETRANSFAIL, segs);
 	}
 	return err;
 }
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 091c53925e4d..f87dbc78b6bc 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -378,7 +378,7 @@ static void tcp_probe_timer(struct sock *sk)
 			return;
 	}
 
-	if (icsk->icsk_probes_out > max_probes) {
+	if (icsk->icsk_probes_out >= max_probes) {
 abort:		tcp_write_err(sk);
 	} else {
 		/* Only send another probe if we didn't close things up. */
@@ -484,11 +484,12 @@ void tcp_retransmit_timer(struct sock *sk)
 		goto out_reset_timer;
 	}
 
+	__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPTIMEOUTS);
 	if (tcp_write_timeout(sk))
 		goto out;
 
 	if (icsk->icsk_retransmits == 0) {
-		int mib_idx;
+		int mib_idx = 0;
 
 		if (icsk->icsk_ca_state == TCP_CA_Recovery) {
 			if (tcp_is_sack(tp))
@@ -503,10 +504,9 @@ void tcp_retransmit_timer(struct sock *sk)
 				mib_idx = LINUX_MIB_TCPSACKFAILURES;
 			else
 				mib_idx = LINUX_MIB_TCPRENOFAILURES;
-		} else {
-			mib_idx = LINUX_MIB_TCPTIMEOUTS;
 		}
-		__NET_INC_STATS(sock_net(sk), mib_idx);
+		if (mib_idx)
+			__NET_INC_STATS(sock_net(sk), mib_idx);
 	}
 
 	tcp_enter_loss(sk);