From 8d81b35c4449c9abde4b0b98bec9d9eaf36e7809 Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Fri, 7 Jul 2017 08:50:01 -0600
Subject: [PATCH] network:  Correct some issues that prevent TCP from working
 correctly when both IPv4 and IPv6 are enabled.

---
 net/socket/send.c             | 1 +
 net/tcp/tcp_input.c           | 2 +-
 net/tcp/tcp_send_buffered.c   | 2 +-
 net/tcp/tcp_send_unbuffered.c | 2 +-
 4 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/socket/send.c b/net/socket/send.c
index 33060b5a32..c47158aca2 100644
--- a/net/socket/send.c
+++ b/net/socket/send.c
@@ -255,6 +255,7 @@ ssize_t psock_send(FAR struct socket *psock, FAR const void *buf, size_t len,
       set_errno(-ret);
       ret = ERROR;
     }
+
   return ret;
 }
 
diff --git a/net/tcp/tcp_input.c b/net/tcp/tcp_input.c
index 8b34988401..aefde83fd2 100644
--- a/net/tcp/tcp_input.c
+++ b/net/tcp/tcp_input.c
@@ -285,7 +285,7 @@ static void tcp_input(FAR struct net_driver_s *dev, uint8_t domain,
         }
     }
 
-  nwarn("WARNING: Old packet .. reset\n");
+  nwarn("WARNING: SYN with no listener (or old packet) .. reset\n");
 
   /* This is (1) an old duplicate packet or (2) a SYN packet but with
    * no matching listener found.  Send RST packet in either case.
diff --git a/net/tcp/tcp_send_buffered.c b/net/tcp/tcp_send_buffered.c
index 7ecf990326..afb8355a34 100644
--- a/net/tcp/tcp_send_buffered.c
+++ b/net/tcp/tcp_send_buffered.c
@@ -243,7 +243,7 @@ static inline void send_ipselect(FAR struct net_driver_s *dev,
       /* Select the IPv6 domain */
 
       DEBUGASSERT(conn->domain == PF_INET6);
-      tcp_ipv4_select(dev);
+      tcp_ipv6_select(dev);
     }
 }
 #endif
diff --git a/net/tcp/tcp_send_unbuffered.c b/net/tcp/tcp_send_unbuffered.c
index e4d4a50d4f..e9f2a92627 100644
--- a/net/tcp/tcp_send_unbuffered.c
+++ b/net/tcp/tcp_send_unbuffered.c
@@ -194,7 +194,7 @@ static inline void tcpsend_ipselect(FAR struct net_driver_s *dev,
       /* Select the IPv6 domain */
 
       DEBUGASSERT(conn->domain == PF_INET6);
-      tcp_ipv4_select(dev);
+      tcp_ipv6_select(dev);
     }
 }
 #endif