diff --git a/Lib/test/test_cgi.py b/Lib/test/test_cgi.py
--- a/Lib/test/test_cgi.py
+++ b/Lib/test/test_cgi.py
@@ -261,16 +261,44 @@ Content-Disposition: form-data; name="su
                   {'name':'title', 'filename':None, 'value':''},
                   {'name':'file', 'filename':'test.txt','value':'Testing 123.\n'},
                   {'name':'submit', 'filename':None, 'value':' Add '}]
         for x in range(len(fs.list)):
             for k, exp in expect[x].items():
                 got = getattr(fs.list[x], k)
                 self.assertEqual(got, exp)
 
+    def test_fieldstorage_multipart_baddata_oneblock(self):
+        data = "0" * 65535
+        env = {'REQUEST_METHOD': 'POST', 'CONTENT_TYPE': 'multipart/form-data; boundary=---------------------------721837373350705526688164684', 'CONTENT_LENGTH': str(len(data))}
+        postdata = "\r\n".join(
+            ['-----------------------------721837373350705526688164684',
+             'Content-Disposition: form-data; name="data"; filename="thefile.txt"',
+             '',
+             data,
+             '-----------------------------721837373350705526688164684--',
+             ]) + "\r\n"
+        fs = cgi.FieldStorage(fp=StringIO(postdata), environ=env)
+        self.assertEqual(len(fs.list), 1)
+        self.assertEqual(fs['data'].value, data, "data mismatch (%i,%i bytes)" % (len(fs['data'].value), len(data)))
+
+    def test_fieldstorage_multipart_baddata_manyblocks(self):
+        data = "0" * 65535 + "\r\n" + "0" * 65535 + "\r" + "0" * 65535
+        env = {'REQUEST_METHOD': 'POST', 'CONTENT_TYPE': 'multipart/form-data; boundary=---------------------------721837373350705526688164684', 'CONTENT_LENGTH': str(len(data))}
+        postdata = "\r\n".join(
+            ['-----------------------------721837373350705526688164684',
+             'Content-Disposition: form-data; name="data"; filename="thefile.txt"',
+             '',
+             data,
+             '-----------------------------721837373350705526688164684--',
+             ]) + "\r\n"
+        fs = cgi.FieldStorage(fp=StringIO(postdata), environ=env)
+        self.assertEqual(len(fs.list), 1)
+        self.assertEqual(fs['data'].value, data, "data mismatch (%i,%i bytes)" % (len(fs['data'].value), len(data)))
+
     _qs_result = {
         'key1': 'value1',
         'key2': ['value2x', 'value2y'],
         'key3': 'value3',
         'key4': 'value4'
     }
     def testQSAndUrlEncode(self):
         data = "key2=value2x&key3=value3&key4=value4"