[TCP]: Fix init_cwnd calculations in tcp_select_initial_window()

Match it up to what RFC2414 really specifies.
Noticed by Rick Jones.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 5 deletions

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index d6e3d269e906..caf2e2cff293 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -190,15 +190,16 @@ void tcp_select_initial_window(int __space, __u32 mss,
         }
 
         /* Set initial window to value enough for senders,
-         * following RFC1414. Senders, not following this RFC,
+         * following RFC2414. Senders, not following this RFC,
          * will be satisfied with 2.
          */
         if (mss > (1<<*rcv_wscale)) {
-                int init_cwnd = 4;
-                if (mss > 1460*3)
+                int init_cwnd;
+
+                if (mss > 1460)
                         init_cwnd = 2;
-                else if (mss > 1460)
-                        init_cwnd = 3;
+                else
+                        init_cwnd = (mss > 1095) ? 3 : 4;
                 if (*rcv_wnd > init_cwnd*mss)
                         *rcv_wnd = init_cwnd*mss;
         }