Index: Lib/test/test_fileio.py
===================================================================
--- Lib/test/test_fileio.py	(revision 81232)
+++ Lib/test/test_fileio.py	(working copy)
@@ -310,8 +310,10 @@
             os.unlink(TESTFN)
 
     def testInvalidFd(self):
-        self.assertRaises(ValueError, _FileIO, -10)
+        self.assertRaises(ValueError, _FileIO, -10) 
         self.assertRaises(OSError, _FileIO, make_bad_fd())
+        import msvcrt
+        self.assertRaises(IOError, msvcrt.get_osfhandle, make_bad_fd())
 
     def testBadModeArgument(self):
         # verify that we get a sensible error message for bad mode argument
Index: PC/msvcrtmodule.c
===================================================================
--- PC/msvcrtmodule.c	(revision 81232)
+++ PC/msvcrtmodule.c	(working copy)
@@ -141,7 +141,11 @@
     if (!PyArg_ParseTuple(args,"i:get_osfhandle", &fd))
         return NULL;
 
+    if (!_PyVerify_fd(fd))
+        return PyErr_SetFromErrno(PyExc_IOError);
+
     handle = _get_osfhandle(fd);
+
     if (handle == -1)
         return PyErr_SetFromErrno(PyExc_IOError);