close websocket if proxyReq is closed before upgrade

avoids leaving client sockets open when upstream
connections are rejected.

lib/http-proxy/passes/ws-incoming.js

@@ -89,8 +89,19 @@ var passes = exports;
  );
  // Error Handler
  proxyReq.on('error', onOutgoingError);
+ var upgraded = false;
+ proxyReq.on('close', function () {
+ if (!upgraded) {
+ try {
+ socket.end();
+ } catch (e) {
+ // ignore failure to teardown socket
+ }
+ }
+ });
 
  proxyReq.on('upgrade', function(proxyRes, proxySocket, proxyHead) {
+ upgraded = true;
  proxySocket.on('error', onOutgoingError);
  // The pipe below will end proxySocket if socket closes cleanly, but not
  // if it errors (eg, vanishes from the net and starts returning