[tor-bugs] #2812 [Torctl]: TorCtl Zombie Connections

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#2812: TorCtl Zombie Connections
--------------------+-------------------------------------------------------
 Reporter:  atagar  |          Owner:              
     Type:  defect  |         Status:  needs_review
 Priority:  normal  |      Milestone:              
Component:  Torctl  |        Version:              
 Keywords:          |         Parent:              
   Points:          |   Actualpoints:              
--------------------+-------------------------------------------------------

Comment(by atagar):

 Pesky. The proper solution is to add 'self._s.shutdown(socket.SHUT_RDWR)'
 prior to the close in TorUtil.BufSocket. That is to say...

 Index: src/TorCtl/TorUtil.py
 ===================================================================
 --- src/TorCtl/TorUtil.py       (revision 24405)
 +++ src/TorCtl/TorUtil.py       (working copy)
 @@ -221,6 +221,7 @@
      self._s.send(s)

    def close(self):
 +    self._s.shutdown(socket.SHUT_RDWR)
      self._s.close()

  # SocketServer.TCPServer is nuts..
 Index: src/TorCtl/TorCtl.py
 ===================================================================
 --- src/TorCtl/TorCtl.py        (revision 24499)
 +++ src/TorCtl/TorCtl.py        (working copy)
 @@ -109,7 +109,7 @@
                    than prompting the user)
    """

 -  s = None
 +  conn = None
    try:
      s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
      s.connect((controlAddr, controlPort))
 @@ -133,10 +133,10 @@
        print "Connection refused. Is the ControlPort enabled?"
      else: print "Failed to establish socket: %s" % exc

 -    if s: s.shutdown(socket.SHUT_RDWR)
 +    if conn: conn.close()
      return None
    except Exception, exc:
 -    if s: s.shutdown(socket.SHUT_RDWR)
 +    if conn: conn.close()

      if passphrase and str(exc) == "Unable to authenticate: password
 incorrect":
        # provide a warning that the provided password didn't work, then
 try

 ===================================================================

 In general this works fine, except that when I try to join on
 TorCtl.Connection._thread after the close() it runs into deadlock
 (evidently this change means that _loop never terminates, my guess is that
 _read_reply() is blocking).

 I'm not quite sure of the proper workaround for this. The earlier fix
 addresses the issue I'm primarily concerned about with arm so I'll leave
 it with that for now. -Damian

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2812#comment:4>
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