- Issue #5104: The socket module now raises OverflowError when 16-bit port and

protocol numbers are supplied outside the allowed 0-65536 range on bind()
  and getservbyport().

Lib/test/test_socket.py

@@ -356,6 +356,9 @@ class GeneralModuleTests(unittest.TestCase):
         eq(socket.getservbyport(port, 'tcp'), service)
         if udpport is not None:
             eq(socket.getservbyport(udpport, 'udp'), service)
+        # Make sure getservbyport does not accept out of range ports.
+        self.assertRaises(OverflowError, socket.getservbyport, -1)
+        self.assertRaises(OverflowError, socket.getservbyport, 65536)
 
     def testDefaultTimeout(self):
         # Testing default timeout
@@ -456,15 +459,23 @@ class GeneralModuleTests(unittest.TestCase):
 
     # XXX The following don't test module-level functionality...
 
-    def testSockName(self):
-        # Testing getsockname().  Use a temporary socket to elicit an unused
-        # ephemeral port that we can use later in the test.
-        tempsock = socket.socket()
-        tempsock.bind(("0.0.0.0", 0))
-        (host, port) = tempsock.getsockname()
-        tempsock.close()
-        del tempsock
+    def _get_unused_port(self, bind_address='0.0.0.0'):
+        """Use a temporary socket to elicit an unused ephemeral port.
 
+        Args:
+            bind_address: Hostname or IP address to search for a port on.
+
+        Returns: A most likely to be unused port.
+        """
+        tempsock = socket.socket()
+        tempsock.bind((bind_address, 0))
+        host, port = tempsock.getsockname()
+        tempsock.close()
+        return port
+
+    def testSockName(self):
+        # Testing getsockname()
+        port = self._get_unused_port()
         sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
         sock.bind(("0.0.0.0", port))
         name = sock.getsockname()
@@ -504,6 +515,19 @@ class GeneralModuleTests(unittest.TestCase):
         self.assertEqual(sock.proto, 0)
         sock.close()
 
+    def test_getsockaddrarg(self):
+        host = '0.0.0.0'
+        port = self._get_unused_port(bind_address=host)
+        big_port = port + 65536
+        neg_port = port - 65536
+        sock = socket.socket()
+        try:
+            self.assertRaises(OverflowError, sock.bind, (host, big_port))
+            self.assertRaises(OverflowError, sock.bind, (host, neg_port))
+            sock.bind((host, port))
+        finally:
+            sock.close()
+
     def test_sock_ioctl(self):
         if os.name != "nt":
             return