1 files changed, 19 insertions, 10 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index b54d9d37b636..54a0b7412782 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2483,6 +2483,20 @@ static inline void tcp_complete_cwr(struct sock *sk)
         tcp_ca_event(sk, CA_EVENT_COMPLETE_CWR);
 }
 
+static void tcp_try_keep_open(struct sock *sk)
+{
+        struct tcp_sock *tp = tcp_sk(sk);
+        int state = TCP_CA_Open;
+
+        if (tcp_left_out(tp) || tp->retrans_out || tp->undo_marker)
+                state = TCP_CA_Disorder;
+
+        if (inet_csk(sk)->icsk_ca_state != state) {
+                tcp_set_ca_state(sk, state);
+                tp->high_seq = tp->snd_nxt;
+        }
+}
+
 static void tcp_try_to_open(struct sock *sk, int flag)
 {
         struct tcp_sock *tp = tcp_sk(sk);
@@ -2496,15 +2510,7 @@ static void tcp_try_to_open(struct sock *sk, int flag)
                 tcp_enter_cwr(sk, 1);
 
         if (inet_csk(sk)->icsk_ca_state != TCP_CA_CWR) {
-                int state = TCP_CA_Open;
-
-                if (tcp_left_out(tp) || tp->retrans_out || tp->undo_marker)
-                        state = TCP_CA_Disorder;
-
-                if (inet_csk(sk)->icsk_ca_state != state) {
-                        tcp_set_ca_state(sk, state);
-                        tp->high_seq = tp->snd_nxt;
-                }
+                tcp_try_keep_open(sk);
                 tcp_moderate_cwnd(tp);
         } else {
                 tcp_cwnd_down(sk, flag);
@@ -3310,8 +3316,11 @@ no_queue:
         return 1;
 
 old_ack:
-        if (TCP_SKB_CB(skb)->sacked)
+        if (TCP_SKB_CB(skb)->sacked) {
                 tcp_sacktag_write_queue(sk, skb, prior_snd_una);
+                if (icsk->icsk_ca_state == TCP_CA_Open)
+                        tcp_try_keep_open(sk);
+        }
 
 uninteresting_ack:
         SOCK_DEBUG(sk, "Ack %u out of %u:%u\n", ack, tp->snd_una, tp->snd_nxt);