bpo-34226: fix cgi.parse_multipart without content_length (GH-8530)
In Python 3.7 the behavior of parse_multipart changed requiring CONTENT-LENGTH
header, this fix remove this header as required and fix FieldStorage
read_lines_to_outerboundary, by not using limit when it's negative,
since by default it's -1 if not content-length and keeps substracting what
was read from the file object.
Also added a test case for this problem.
diff --git a/Lib/cgi.py b/Lib/cgi.py
index c22c71b..77ab703 100755
--- a/Lib/cgi.py
+++ b/Lib/cgi.py
@@ -200,7 +200,10 @@
ctype = "multipart/form-data; boundary={}".format(boundary)
headers = Message()
headers.set_type(ctype)
- headers['Content-Length'] = pdict['CONTENT-LENGTH']
+ try:
+ headers['Content-Length'] = pdict['CONTENT-LENGTH']
+ except KeyError:
+ pass
fs = FieldStorage(fp, headers=headers, encoding=encoding, errors=errors,
environ={'REQUEST_METHOD': 'POST'})
return {k: fs.getlist(k) for k in fs}
@@ -736,7 +739,8 @@
last_line_lfend = True
_read = 0
while 1:
- if self.limit is not None and _read >= self.limit:
+
+ if self.limit is not None and 0 <= self.limit <= _read:
break
line = self.fp.readline(1<<16) # bytes
self.bytes_read += len(line)
diff --git a/Lib/test/test_cgi.py b/Lib/test/test_cgi.py
index ab86771..101942d 100644
--- a/Lib/test/test_cgi.py
+++ b/Lib/test/test_cgi.py
@@ -128,6 +128,20 @@
'file': [b'Testing 123.\n'], 'title': ['']}
self.assertEqual(result, expected)
+ def test_parse_multipart_without_content_length(self):
+ POSTDATA = '''--JfISa01
+Content-Disposition: form-data; name="submit-name"
+
+just a string
+
+--JfISa01--
+'''
+ fp = BytesIO(POSTDATA.encode('latin1'))
+ env = {'boundary': 'JfISa01'.encode('latin1')}
+ result = cgi.parse_multipart(fp, env)
+ expected = {'submit-name': ['just a string\n']}
+ self.assertEqual(result, expected)
+
def test_parse_multipart_invalid_encoding(self):
BOUNDARY = "JfISa01"
POSTDATA = """--JfISa01