diff -r 8e1ed2a15845 -r 4690a2871b44 src/java.net.http/share/classes/jdk/internal/net/http/AsyncSSLTunnelConnection.java
--- a/src/java.net.http/share/classes/jdk/internal/net/http/AsyncSSLTunnelConnection.java	Wed May 02 10:47:16 2018 +0200
+++ b/src/java.net.http/share/classes/jdk/internal/net/http/AsyncSSLTunnelConnection.java	Wed May 02 02:36:17 2018 -0700
@@ -65,6 +65,7 @@
                     // create the SSLTube wrapping the SocketTube, with the given engine
                     flow = new SSLTube(engine,
                                        client().theExecutor(),
+                                       client().getSSLBufferSupplier()::recycle,
                                        plainConnection.getConnectionFlow());
                     return null;} );
     }