1 files changed, 11 insertions, 2 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 88693281da4c..c5cfd5ec3184 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -2860,10 +2860,19 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn)
 {
         struct tcp_sock *tp = tcp_sk(sk);
         struct tcp_fastopen_request *fo = tp->fastopen_req;
-        int space, i, err = 0, iovlen = fo->data->msg_iovlen;
+        int syn_loss = 0, space, i, err = 0, iovlen = fo->data->msg_iovlen;
         struct sk_buff *syn_data = NULL, *data;
+        unsigned long last_syn_loss = 0;
+
+        tcp_fastopen_cache_get(sk, &tp->rx_opt.mss_clamp, &fo->cookie,
+                               &syn_loss, &last_syn_loss);
+        /* Recurring FO SYN losses: revert to regular handshake temporarily */
+        if (syn_loss > 1 &&
+            time_before(jiffies, last_syn_loss + (60*HZ << syn_loss))) {
+                fo->cookie.len = -1;
+                goto fallback;
+        }
 
-        tcp_fastopen_cache_get(sk, &tp->rx_opt.mss_clamp, &fo->cookie);
         if (fo->cookie.len <= 0)
                 goto fallback;