From 76c1a6ae479fe06911149e45e293d2fd5e17038b Mon Sep 17 00:00:00 2001
From: Unknown <chris@eykamp.com>
Date: Tue, 19 Jun 2018 11:36:55 -0700
Subject: [PATCH 1/2] Proposed fixes for issue 27777

---
 Lib/cgi.py           |  6 +-----
 Lib/test/test_cgi.py | 15 ++++++++++++++-
 2 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/Lib/cgi.py b/Lib/cgi.py
index f82cc6c8bd56d3..ebe1210ddb4b74 100755
--- a/Lib/cgi.py
+++ b/Lib/cgi.py
@@ -646,10 +646,6 @@ def read_multi(self, environ, keep_blank_values, strict_parsing):
             parser.feed(hdr_text.decode(self.encoding, self.errors))
             headers = parser.close()
 
-            # Some clients add Content-Length for part headers, ignore them
-            if 'content-length' in headers:
-                del headers['content-length']
-
             part = klass(self.fp, headers, ib, environ, keep_blank_values,
                          strict_parsing,self.limit-self.bytes_read,
                          self.encoding, self.errors)
@@ -818,7 +814,7 @@ def make_file(self):
         which unlinks the temporary files you have created.
 
         """
-        if self._binary_file:
+        if self._binary_file or self.length >= 0:
             return tempfile.TemporaryFile("wb+")
         else:
             return tempfile.TemporaryFile("w+",
diff --git a/Lib/test/test_cgi.py b/Lib/test/test_cgi.py
index 4f2bba14a1bdc4..6863c0fd522a6e 100644
--- a/Lib/test/test_cgi.py
+++ b/Lib/test/test_cgi.py
@@ -361,7 +361,20 @@ def test_fieldstorage_part_content_length(self):
         fs = cgi.FieldStorage(fp, environ=env, encoding="latin-1")
         self.assertEqual(len(fs.list), 1)
         self.assertEqual(fs.list[0].name, 'submit-name')
-        self.assertEqual(fs.list[0].value, 'Larry')
+        self.assertEqual(fs.list[0].value, b'Larry')
+
+    def test_fieldstorage_not_multipart(self):
+        POSTDATA = b'{"name": "Bert"}'
+
+        env = {
+            'REQUEST_METHOD': 'POST',
+            'CONTENT_TYPE': 'text/plain',
+            'CONTENT_LENGTH': str(len(POSTDATA))
+        }
+        fp = BytesIO(POSTDATA)
+        fs = cgi.FieldStorage(fp, environ=env)
+        self.assertEqual(fs.list, None)
+        self.assertEqual(fs.value, b'{"name": "Bert"}')
 
     def test_fieldstorage_as_context_manager(self):
         fp = BytesIO(b'x' * 10)

From 0ebe13854d3278b6dd3deb29cd924b005ee40e1a Mon Sep 17 00:00:00 2001
From: Unknown <chris@eykamp.com>
Date: Tue, 19 Jun 2018 12:04:39 -0700
Subject: [PATCH 2/2] Add blurb describing fix

---
 .../Core and Builtins/2018-06-19-12-02-47.bpo-27777.Uw2zdd.rst | 3 +++
 1 file changed, 3 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Core and Builtins/2018-06-19-12-02-47.bpo-27777.Uw2zdd.rst

diff --git a/Misc/NEWS.d/next/Core and Builtins/2018-06-19-12-02-47.bpo-27777.Uw2zdd.rst b/Misc/NEWS.d/next/Core and Builtins/2018-06-19-12-02-47.bpo-27777.Uw2zdd.rst
new file mode 100644
index 00000000000000..9427e148f48899
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2018-06-19-12-02-47.bpo-27777.Uw2zdd.rst	
@@ -0,0 +1,3 @@
+Fix issue in cgi.py sending requests with Content-Length but without
+Content-Disposition headers, also choosing between creating files in text or
+binary mode.