title: Python DNS server address already in use
body: <p>I'm doing lab in Malware analysis.<br>
  The task is to investigate CVE-2015-7547 glibc vulnerability.</p>
  
  <p>Google already gave <a href="https://github.com/fjserna/CVE-2015-7547" rel="nofollow">proof of concept code</a>. This code contains client in C and  fake DNS server in python. When I try to run server, it throws exception:</p>
  
  <pre><code>turbolab@sandbox:~/Desktop$ sudo python CVE-2015-7547-poc.py 
  Traceback (most recent call last):
   File "CVE-2015-7547-poc.py", line 176, in &lt;module&gt;
      tcp_thread()
    File "CVE-2015-7547-poc.py", line 101, in tcp_thread
      sock_tcp.bind((IP, 53))
    File "/usr/lib/python2.7/socket.py", line 224, in meth
      return getattr(self._sock,name)(*args)
  socket.error: [Errno 98] Address already in use
  </code></pre>
  
  <p>IP was set to 127.0.0.1.</p>
  
  <p>How to run server and connect client to it?</p>