1 files changed, 23 insertions, 8 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 2868ef28ce52..a9d9555a973f 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -579,10 +579,12 @@ static inline void tcp_rcv_rtt_measure_ts(struct sock *sk,
 		u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr;
 		u32 delta_us;
 
-		if (!delta)
-			delta = 1;
-		delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ);
-		tcp_rcv_rtt_update(tp, delta_us, 0);
+		if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) {
+			if (!delta)
+				delta = 1;
+			delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ);
+			tcp_rcv_rtt_update(tp, delta_us, 0);
+		}
 	}
 }
 
@@ -2910,9 +2912,11 @@ static bool tcp_ack_update_rtt(struct sock *sk, const int flag,
 	if (seq_rtt_us < 0 && tp->rx_opt.saw_tstamp && tp->rx_opt.rcv_tsecr &&
 	    flag & FLAG_ACKED) {
 		u32 delta = tcp_time_stamp(tp) - tp->rx_opt.rcv_tsecr;
-		u32 delta_us = delta * (USEC_PER_SEC / TCP_TS_HZ);
 
-		seq_rtt_us = ca_rtt_us = delta_us;
+		if (likely(delta < INT_MAX / (USEC_PER_SEC / TCP_TS_HZ))) {
+			seq_rtt_us = delta * (USEC_PER_SEC / TCP_TS_HZ);
+			ca_rtt_us = seq_rtt_us;
+		}
 	}
 	rs->rtt_us = ca_rtt_us; /* RTT of last (S)ACKed packet (or -1) */
 	if (seq_rtt_us < 0)
@@ -4268,7 +4272,7 @@ static void tcp_sack_new_ofo_skb(struct sock *sk, u32 seq, u32 end_seq)
 	 * If the sack array is full, forget about the last one.
 	 */
 	if (this_sack >= TCP_NUM_SACKS) {
-		if (tp->compressed_ack)
+		if (tp->compressed_ack > TCP_FASTRETRANS_THRESH)
 			tcp_send_ack(sk);
 		this_sack--;
 		tp->rx_opt.num_sacks--;
@@ -4363,6 +4367,7 @@ static bool tcp_try_coalesce(struct sock *sk,
 	if (TCP_SKB_CB(from)->has_rxtstamp) {
 		TCP_SKB_CB(to)->has_rxtstamp = true;
 		to->tstamp = from->tstamp;
+		skb_hwtstamps(to)->hwtstamp = skb_hwtstamps(from)->hwtstamp;
 	}
 
 	return true;
@@ -5188,7 +5193,17 @@ send_now:
 	if (!tcp_is_sack(tp) ||
 	    tp->compressed_ack >= sock_net(sk)->ipv4.sysctl_tcp_comp_sack_nr)
 		goto send_now;
-	tp->compressed_ack++;
+
+	if (tp->compressed_ack_rcv_nxt != tp->rcv_nxt) {
+		tp->compressed_ack_rcv_nxt = tp->rcv_nxt;
+		if (tp->compressed_ack > TCP_FASTRETRANS_THRESH)
+			NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPACKCOMPRESSED,
+				      tp->compressed_ack - TCP_FASTRETRANS_THRESH);
+		tp->compressed_ack = 0;
+	}
+
+	if (++tp->compressed_ack <= TCP_FASTRETRANS_THRESH)
+		goto send_now;
 
 	if (hrtimer_is_queued(&tp->compressed_ack_timer))
 		return;