diff --git a/SOURCES/00359-CVE-2021-23336.patch b/SOURCES/00359-CVE-2021-23336.patch new file mode 100644 index 0000000..4a0c31e --- /dev/null +++ b/SOURCES/00359-CVE-2021-23336.patch @@ -0,0 +1,684 @@ +commit 9e77ec82c40ab59846f9447b7c483e7b8e368b16 +Author: Petr Viktorin +Date: Thu Mar 4 13:59:56 2021 +0100 + + CVE-2021-23336: Add `separator` argument to parse_qs; warn with default + + Partially backports https://bugs.python.org/issue42967 : [security] Address a web cache-poisoning issue reported in urllib.parse.parse_qsl(). + However, this solution is different than the upstream solution in Python 3.6.13. + + An optional argument seperator is added to specify the separator. + It is recommended to set it to '&' or ';' to match the application or proxy in use. + The default can be set with an env variable of a config file. + If neither the argument, env var or config file specifies a separator, "&" is used + but a warning is raised if parse_qs is used on input that contains ';'. + + Co-authors of the upstream change (who do not necessarily agree with this): + Co-authored-by: Adam Goldschmidt + Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com> + Co-authored-by: Éric Araujo + +diff --git a/Doc/library/cgi.rst b/Doc/library/cgi.rst +index 41219eeaaba..ddecc0af23a 100644 +--- a/Doc/library/cgi.rst ++++ b/Doc/library/cgi.rst +@@ -277,13 +277,12 @@ These are useful if you want more control, or if you want to employ some of the + algorithms implemented in this module in other circumstances. + + +-.. function:: parse(fp=None, environ=os.environ, keep_blank_values=False, strict_parsing=False) ++.. function:: parse(fp=None, environ=os.environ, keep_blank_values=False, strict_parsing=False, separator=None) + + Parse a query in the environment or from a file (the file defaults to +- ``sys.stdin``). The *keep_blank_values* and *strict_parsing* parameters are ++ ``sys.stdin``). The *keep_blank_values*, *strict_parsing* and *separator* parameters are + passed to :func:`urllib.parse.parse_qs` unchanged. + +- + .. function:: parse_qs(qs, keep_blank_values=False, strict_parsing=False) + + This function is deprecated in this module. Use :func:`urllib.parse.parse_qs` +@@ -308,7 +307,6 @@ algorithms implemented in this module in other circumstances. + Note that this does not parse nested multipart parts --- use + :class:`FieldStorage` for that. + +- + .. function:: parse_header(string) + + Parse a MIME header (such as :mailheader:`Content-Type`) into a main value and a +diff --git a/Doc/library/urllib.parse.rst b/Doc/library/urllib.parse.rst +index 647af613a31..bcab7c142bc 100644 +--- a/Doc/library/urllib.parse.rst ++++ b/Doc/library/urllib.parse.rst +@@ -143,7 +143,7 @@ or on combining URL components into a URL string. + now raise :exc:`ValueError`. + + +-.. function:: parse_qs(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None) ++.. function:: parse_qs(qs, keep_blank_values=False, strict_parsing=False, encoding='utf-8', errors='replace', max_num_fields=None, separator=None) + + Parse a query string given as a string argument (data of type + :mimetype:`application/x-www-form-urlencoded`). Data are returned as a +@@ -168,6 +168,15 @@ or on combining URL components into a URL string. + read. If set, then throws a :exc:`ValueError` if there are more than + *max_num_fields* fields read. + ++ The optional argument *separator* is the symbol to use for separating the ++ query arguments. It is recommended to set it to ``'&'`` or ``';'``. ++ It defaults to ``'&'``; a warning is raised if this default is used. ++ This default may be changed with the following environment variable settings: ++ ++ - ``PYTHON_URLLIB_QS_SEPARATOR='&'``: use only ``&`` as separator, without warning (as in Python 3.6.13+ or 3.10) ++ - ``PYTHON_URLLIB_QS_SEPARATOR=';'``: use only ``;`` as separator ++ - ``PYTHON_URLLIB_QS_SEPARATOR=legacy``: use both ``&`` and ``;`` (as in previous versions of Python) ++ + Use the :func:`urllib.parse.urlencode` function (with the ``doseq`` + parameter set to ``True``) to convert such dictionaries into query + strings. +@@ -204,6 +213,9 @@ or on combining URL components into a URL string. + read. If set, then throws a :exc:`ValueError` if there are more than + *max_num_fields* fields read. + ++ The optional argument *separator* is the symbol to use for separating the ++ query arguments. It works as in :py:func:`parse_qs`. ++ + Use the :func:`urllib.parse.urlencode` function to convert such lists of pairs into + query strings. + +@@ -213,7 +225,6 @@ or on combining URL components into a URL string. + .. versionchanged:: 3.6.8 + Added *max_num_fields* parameter. + +- + .. function:: urlunparse(parts) + + Construct a URL from a tuple as returned by ``urlparse()``. The *parts* +diff --git a/Lib/cgi.py b/Lib/cgi.py +index 56f243e09f0..5ab2a5d6af6 100755 +--- a/Lib/cgi.py ++++ b/Lib/cgi.py +@@ -117,7 +117,8 @@ log = initlog # The current logging function + # 0 ==> unlimited input + maxlen = 0 + +-def parse(fp=None, environ=os.environ, keep_blank_values=0, strict_parsing=0): ++def parse(fp=None, environ=os.environ, keep_blank_values=0, ++ strict_parsing=0, separator=None): + """Parse a query in the environment or from a file (default stdin) + + Arguments, all optional: +@@ -136,6 +137,8 @@ def parse(fp=None, environ=os.environ, keep_blank_values=0, strict_parsing=0): + strict_parsing: flag indicating what to do with parsing errors. + If false (the default), errors are silently ignored. + If true, errors raise a ValueError exception. ++ ++ separator: str. The symbol to use for separating the query arguments. + """ + if fp is None: + fp = sys.stdin +@@ -156,7 +159,7 @@ def parse(fp=None, environ=os.environ, keep_blank_values=0, strict_parsing=0): + if environ['REQUEST_METHOD'] == 'POST': + ctype, pdict = parse_header(environ['CONTENT_TYPE']) + if ctype == 'multipart/form-data': +- return parse_multipart(fp, pdict) ++ return parse_multipart(fp, pdict, separator=separator) + elif ctype == 'application/x-www-form-urlencoded': + clength = int(environ['CONTENT_LENGTH']) + if maxlen and clength > maxlen: +@@ -182,21 +185,21 @@ def parse(fp=None, environ=os.environ, keep_blank_values=0, strict_parsing=0): + return urllib.parse.parse_qs(qs, keep_blank_values, strict_parsing, + encoding=encoding) + +- + # parse query string function called from urlparse, + # this is done in order to maintain backward compatibility. +- +-def parse_qs(qs, keep_blank_values=0, strict_parsing=0): ++def parse_qs(qs, keep_blank_values=0, strict_parsing=0, separator=None): + """Parse a query given as a string argument.""" + warn("cgi.parse_qs is deprecated, use urllib.parse.parse_qs instead", + DeprecationWarning, 2) +- return urllib.parse.parse_qs(qs, keep_blank_values, strict_parsing) ++ return urllib.parse.parse_qs(qs, keep_blank_values, strict_parsing, ++ separator=separator) + +-def parse_qsl(qs, keep_blank_values=0, strict_parsing=0): ++def parse_qsl(qs, keep_blank_values=0, strict_parsing=0, separator=None): + """Parse a query given as a string argument.""" + warn("cgi.parse_qsl is deprecated, use urllib.parse.parse_qsl instead", + DeprecationWarning, 2) +- return urllib.parse.parse_qsl(qs, keep_blank_values, strict_parsing) ++ return urllib.parse.parse_qsl(qs, keep_blank_values, strict_parsing, ++ separator=separator) + + def parse_multipart(fp, pdict): + """Parse multipart input. +@@ -297,7 +300,6 @@ def parse_multipart(fp, pdict): + + return partdict + +- + def _parseparam(s): + while s[:1] == ';': + s = s[1:] +@@ -405,7 +407,7 @@ class FieldStorage: + def __init__(self, fp=None, headers=None, outerboundary=b'', + environ=os.environ, keep_blank_values=0, strict_parsing=0, + limit=None, encoding='utf-8', errors='replace', +- max_num_fields=None): ++ max_num_fields=None, separator=None): + """Constructor. Read multipart/* until last part. + + Arguments, all optional: +@@ -453,6 +455,7 @@ class FieldStorage: + self.keep_blank_values = keep_blank_values + self.strict_parsing = strict_parsing + self.max_num_fields = max_num_fields ++ self.separator = separator + if 'REQUEST_METHOD' in environ: + method = environ['REQUEST_METHOD'].upper() + self.qs_on_post = None +@@ -678,7 +681,7 @@ class FieldStorage: + query = urllib.parse.parse_qsl( + qs, self.keep_blank_values, self.strict_parsing, + encoding=self.encoding, errors=self.errors, +- max_num_fields=self.max_num_fields) ++ max_num_fields=self.max_num_fields, separator=self.separator) + self.list = [MiniFieldStorage(key, value) for key, value in query] + self.skip_lines() + +@@ -694,7 +697,7 @@ class FieldStorage: + query = urllib.parse.parse_qsl( + self.qs_on_post, self.keep_blank_values, self.strict_parsing, + encoding=self.encoding, errors=self.errors, +- max_num_fields=self.max_num_fields) ++ max_num_fields=self.max_num_fields, separator=self.separator) + self.list.extend(MiniFieldStorage(key, value) for key, value in query) + + klass = self.FieldStorageClass or self.__class__ +@@ -736,7 +739,8 @@ class FieldStorage: + + part = klass(self.fp, headers, ib, environ, keep_blank_values, + strict_parsing,self.limit-self.bytes_read, +- self.encoding, self.errors, max_num_fields) ++ self.encoding, self.errors, max_num_fields, ++ separator=self.separator) + + if max_num_fields is not None: + max_num_fields -= 1 +diff --git a/Lib/test/test_cgi.py b/Lib/test/test_cgi.py +index b3e2d4cce8e..5ae3e085e1e 100644 +--- a/Lib/test/test_cgi.py ++++ b/Lib/test/test_cgi.py +@@ -55,12 +55,9 @@ parse_strict_test_cases = [ + ("", ValueError("bad query field: ''")), + ("&", ValueError("bad query field: ''")), + ("&&", ValueError("bad query field: ''")), +- (";", ValueError("bad query field: ''")), +- (";&;", ValueError("bad query field: ''")), + # Should the next few really be valid? + ("=", {}), + ("=&=", {}), +- ("=;=", {}), + # This rest seem to make sense + ("=a", {'': ['a']}), + ("&=a", ValueError("bad query field: ''")), +@@ -75,8 +72,6 @@ parse_strict_test_cases = [ + ("a=a+b&b=b+c", {'a': ['a b'], 'b': ['b c']}), + ("a=a+b&a=b+a", {'a': ['a b', 'b a']}), + ("x=1&y=2.0&z=2-3.%2b0", {'x': ['1'], 'y': ['2.0'], 'z': ['2-3.+0']}), +- ("x=1;y=2.0&z=2-3.%2b0", {'x': ['1'], 'y': ['2.0'], 'z': ['2-3.+0']}), +- ("x=1;y=2.0;z=2-3.%2b0", {'x': ['1'], 'y': ['2.0'], 'z': ['2-3.+0']}), + ("Hbc5161168c542333633315dee1182227:key_store_seqid=400006&cuyer=r&view=bustomer&order_id=0bb2e248638833d48cb7fed300000f1b&expire=964546263&lobale=en-US&kid=130003.300038&ss=env", + {'Hbc5161168c542333633315dee1182227:key_store_seqid': ['400006'], + 'cuyer': ['r'], +@@ -164,6 +159,35 @@ class CgiTests(unittest.TestCase): + + env = {'QUERY_STRING': orig} + fs = cgi.FieldStorage(environ=env) ++ if isinstance(expect, dict): ++ # test dict interface ++ self.assertEqual(len(expect), len(fs)) ++ self.assertCountEqual(expect.keys(), fs.keys()) ++ self.assertEqual(fs.getvalue("nonexistent field", "default"), "default") ++ # test individual fields ++ for key in expect.keys(): ++ expect_val = expect[key] ++ self.assertIn(key, fs) ++ if len(expect_val) > 1: ++ self.assertEqual(fs.getvalue(key), expect_val) ++ else: ++ self.assertEqual(fs.getvalue(key), expect_val[0]) ++ ++ def test_separator(self): ++ parse_semicolon = [ ++ ("x=1;y=2.0", {'x': ['1'], 'y': ['2.0']}), ++ ("x=1;y=2.0;z=2-3.%2b0", {'x': ['1'], 'y': ['2.0'], 'z': ['2-3.+0']}), ++ (";", ValueError("bad query field: ''")), ++ (";;", ValueError("bad query field: ''")), ++ ("=;a", ValueError("bad query field: 'a'")), ++ (";b=a", ValueError("bad query field: ''")), ++ ("b;=a", ValueError("bad query field: 'b'")), ++ ("a=a+b;b=b+c", {'a': ['a b'], 'b': ['b c']}), ++ ("a=a+b;a=b+a", {'a': ['a b', 'b a']}), ++ ] ++ for orig, expect in parse_semicolon: ++ env = {'QUERY_STRING': orig} ++ fs = cgi.FieldStorage(separator=';', environ=env) + if isinstance(expect, dict): + # test dict interface + self.assertEqual(len(expect), len(fs)) +diff --git a/Lib/test/test_urlparse.py b/Lib/test/test_urlparse.py +index 68f633ca3a7..1ec86ba0fc2 100644 +--- a/Lib/test/test_urlparse.py ++++ b/Lib/test/test_urlparse.py +@@ -2,6 +2,11 @@ import sys + import unicodedata + import unittest + import urllib.parse ++from test.support import EnvironmentVarGuard ++from warnings import catch_warnings ++import tempfile ++import contextlib ++import os.path + + RFC1808_BASE = "http://a/b/c/d;p?q#f" + RFC2396_BASE = "http://a/b/c/d;p?q" +@@ -32,6 +37,9 @@ parse_qsl_test_cases = [ + (b"&a=b", [(b'a', b'b')]), + (b"a=a+b&b=b+c", [(b'a', b'a b'), (b'b', b'b c')]), + (b"a=1&a=2", [(b'a', b'1'), (b'a', b'2')]), ++] ++ ++parse_qsl_test_cases_semicolon = [ + (";", []), + (";;", []), + (";a=b", [('a', 'b')]), +@@ -44,6 +52,21 @@ parse_qsl_test_cases = [ + (b"a=1;a=2", [(b'a', b'1'), (b'a', b'2')]), + ] + ++parse_qsl_test_cases_legacy = [ ++ (b"a=1;a=2&a=3", [(b'a', b'1'), (b'a', b'2'), (b'a', b'3')]), ++ (b"a=1;b=2&c=3", [(b'a', b'1'), (b'b', b'2'), (b'c', b'3')]), ++ (b"a=1&b=2&c=3;", [(b'a', b'1'), (b'b', b'2'), (b'c', b'3')]), ++] ++ ++parse_qsl_test_cases_warn = [ ++ (";a=b", [(';a', 'b')]), ++ ("a=a+b;b=b+c", [('a', 'a b;b=b c')]), ++ (b";a=b", [(b';a', b'b')]), ++ (b"a=a+b;b=b+c", [(b'a', b'a b;b=b c')]), ++ ("a=1;a=2&a=3", [('a', '1;a=2'), ('a', '3')]), ++ (b"a=1;a=2&a=3", [(b'a', b'1;a=2'), (b'a', b'3')]), ++] ++ + # Each parse_qs testcase is a two-tuple that contains + # a string with the query and a dictionary with the expected result. + +@@ -68,6 +91,9 @@ parse_qs_test_cases = [ + (b"&a=b", {b'a': [b'b']}), + (b"a=a+b&b=b+c", {b'a': [b'a b'], b'b': [b'b c']}), + (b"a=1&a=2", {b'a': [b'1', b'2']}), ++] ++ ++parse_qs_test_cases_semicolon = [ + (";", {}), + (";;", {}), + (";a=b", {'a': ['b']}), +@@ -80,6 +106,24 @@ parse_qs_test_cases = [ + (b"a=1;a=2", {b'a': [b'1', b'2']}), + ] + ++parse_qs_test_cases_legacy = [ ++ ("a=1;a=2&a=3", {'a': ['1', '2', '3']}), ++ ("a=1;b=2&c=3", {'a': ['1'], 'b': ['2'], 'c': ['3']}), ++ ("a=1&b=2&c=3;", {'a': ['1'], 'b': ['2'], 'c': ['3']}), ++ (b"a=1;a=2&a=3", {b'a': [b'1', b'2', b'3']}), ++ (b"a=1;b=2&c=3", {b'a': [b'1'], b'b': [b'2'], b'c': [b'3']}), ++ (b"a=1&b=2&c=3;", {b'a': [b'1'], b'b': [b'2'], b'c': [b'3']}), ++] ++ ++parse_qs_test_cases_warn = [ ++ (";a=b", {';a': ['b']}), ++ ("a=a+b;b=b+c", {'a': ['a b;b=b c']}), ++ (b";a=b", {b';a': [b'b']}), ++ (b"a=a+b;b=b+c", {b'a':[ b'a b;b=b c']}), ++ ("a=1;a=2&a=3", {'a': ['1;a=2', '3']}), ++ (b"a=1;a=2&a=3", {b'a': [b'1;a=2', b'3']}), ++] ++ + class UrlParseTestCase(unittest.TestCase): + + def checkRoundtrips(self, url, parsed, split): +@@ -152,6 +196,40 @@ class UrlParseTestCase(unittest.TestCase): + self.assertEqual(result, expect_without_blanks, + "Error parsing %r" % orig) + ++ def test_qs_default_warn(self): ++ for orig, expect in parse_qs_test_cases_warn: ++ with self.subTest(orig=orig, expect=expect): ++ with catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qs(orig, keep_blank_values=True) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 1) ++ self.assertEqual(w[0].category, urllib.parse._QueryStringSeparatorWarning) ++ ++ def test_qsl_default_warn(self): ++ for orig, expect in parse_qsl_test_cases_warn: ++ with self.subTest(orig=orig, expect=expect): ++ with catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qsl(orig, keep_blank_values=True) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 1) ++ self.assertEqual(w[0].category, urllib.parse._QueryStringSeparatorWarning) ++ ++ def test_default_qs_no_warnings(self): ++ for orig, expect in parse_qs_test_cases: ++ with self.subTest(orig=orig, expect=expect): ++ with catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qs(orig, keep_blank_values=True) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ ++ def test_default_qsl_no_warnings(self): ++ for orig, expect in parse_qsl_test_cases: ++ with self.subTest(orig=orig, expect=expect): ++ with catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qsl(orig, keep_blank_values=True) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ + def test_roundtrips(self): + str_cases = [ + ('file:///tmp/junk.txt', +@@ -885,8 +963,151 @@ class UrlParseTestCase(unittest.TestCase): + with self.assertRaises(ValueError): + urllib.parse.parse_qs('&'.join(['a=a']*11), max_num_fields=10) + with self.assertRaises(ValueError): +- urllib.parse.parse_qs(';'.join(['a=a']*11), max_num_fields=10) ++ urllib.parse.parse_qs(';'.join(['a=a']*11), separator=';', max_num_fields=10) ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qs('SEP'.join(['a=a']*11), separator='SEP', max_num_fields=10) + urllib.parse.parse_qs('&'.join(['a=a']*10), max_num_fields=10) ++ urllib.parse.parse_qs(';'.join(['a=a']*10), separator=';', max_num_fields=10) ++ urllib.parse.parse_qs('SEP'.join(['a=a']*10), separator='SEP', max_num_fields=10) ++ ++ def test_parse_qs_separator_bytes(self): ++ expected = {b'a': [b'1'], b'b': [b'2']} ++ ++ result = urllib.parse.parse_qs(b'a=1;b=2', separator=b';') ++ self.assertEqual(result, expected) ++ result = urllib.parse.parse_qs(b'a=1;b=2', separator=';') ++ self.assertEqual(result, expected) ++ result = urllib.parse.parse_qs('a=1;b=2', separator=';') ++ self.assertEqual(result, {'a': ['1'], 'b': ['2']}) ++ ++ @contextlib.contextmanager ++ def _qsl_sep_config(self, sep): ++ """Context for the given parse_qsl default separator configured in config file""" ++ old_filename = urllib.parse._QS_SEPARATOR_CONFIG_FILENAME ++ urllib.parse._default_qs_separator = None ++ try: ++ with tempfile.TemporaryDirectory() as tmpdirname: ++ filename = os.path.join(tmpdirname, 'conf.cfg') ++ with open(filename, 'w') as file: ++ file.write(f'[parse_qs]\n') ++ file.write(f'PYTHON_URLLIB_QS_SEPARATOR = {sep}') ++ urllib.parse._QS_SEPARATOR_CONFIG_FILENAME = filename ++ yield ++ finally: ++ urllib.parse._QS_SEPARATOR_CONFIG_FILENAME = old_filename ++ urllib.parse._default_qs_separator = None ++ ++ def test_parse_qs_separator_semicolon(self): ++ for orig, expect in parse_qs_test_cases_semicolon: ++ with self.subTest(orig=orig, expect=expect, method='arg'): ++ result = urllib.parse.parse_qs(orig, separator=';') ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ with self.subTest(orig=orig, expect=expect, method='env'): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = ';' ++ result = urllib.parse.parse_qs(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ with self.subTest(orig=orig, expect=expect, method='conf'): ++ with self._qsl_sep_config(';'), catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qs(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ ++ def test_parse_qsl_separator_semicolon(self): ++ for orig, expect in parse_qsl_test_cases_semicolon: ++ with self.subTest(orig=orig, expect=expect, method='arg'): ++ result = urllib.parse.parse_qsl(orig, separator=';') ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ with self.subTest(orig=orig, expect=expect, method='env'): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = ';' ++ result = urllib.parse.parse_qsl(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ with self.subTest(orig=orig, expect=expect, method='conf'): ++ with self._qsl_sep_config(';'), catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qsl(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ ++ def test_parse_qs_separator_legacy(self): ++ for orig, expect in parse_qs_test_cases_legacy: ++ with self.subTest(orig=orig, expect=expect, method='env'): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = 'legacy' ++ result = urllib.parse.parse_qs(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ with self.subTest(orig=orig, expect=expect, method='conf'): ++ with self._qsl_sep_config('legacy'), catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qs(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ ++ def test_parse_qsl_separator_legacy(self): ++ for orig, expect in parse_qsl_test_cases_legacy: ++ with self.subTest(orig=orig, expect=expect, method='env'): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = 'legacy' ++ result = urllib.parse.parse_qsl(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ with self.subTest(orig=orig, expect=expect, method='conf'): ++ with self._qsl_sep_config('legacy'), catch_warnings(record=True) as w: ++ result = urllib.parse.parse_qsl(orig) ++ self.assertEqual(result, expect, "Error parsing %r" % orig) ++ self.assertEqual(len(w), 0) ++ ++ def test_parse_qs_separator_bad_value_env_or_config(self): ++ for bad_sep in '', 'abc', 'safe', '&;', 'SEP': ++ with self.subTest(bad_sep, method='env'): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = bad_sep ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qsl('a=1;b=2') ++ with self.subTest(bad_sep, method='conf'): ++ with self._qsl_sep_config('bad_sep'), catch_warnings(record=True) as w: ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qsl('a=1;b=2') ++ ++ def test_parse_qs_separator_bad_value_arg(self): ++ for bad_sep in True, {}, '': ++ with self.subTest(bad_sep): ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qsl('a=1;b=2', separator=bad_sep) ++ ++ def test_parse_qs_separator_num_fields(self): ++ for qs, sep in ( ++ ('a&b&c', '&'), ++ ('a;b;c', ';'), ++ ('a&b;c', 'legacy'), ++ ): ++ with self.subTest(qs=qs, sep=sep): ++ with EnvironmentVarGuard() as environ, catch_warnings(record=True) as w: ++ if sep != 'legacy': ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qsl(qs, separator=sep, max_num_fields=2) ++ if sep: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = sep ++ with self.assertRaises(ValueError): ++ urllib.parse.parse_qsl(qs, max_num_fields=2) ++ ++ def test_parse_qs_separator_priority(self): ++ # env variable trumps config file ++ with self._qsl_sep_config('~'), EnvironmentVarGuard() as environ: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = '!' ++ result = urllib.parse.parse_qs('a=1!b=2~c=3') ++ self.assertEqual(result, {'a': ['1'], 'b': ['2~c=3']}) ++ # argument trumps config file ++ with self._qsl_sep_config('~'): ++ result = urllib.parse.parse_qs('a=1$b=2~c=3', separator='$') ++ self.assertEqual(result, {'a': ['1'], 'b': ['2~c=3']}) ++ # argument trumps env variable ++ with EnvironmentVarGuard() as environ: ++ environ['PYTHON_URLLIB_QS_SEPARATOR'] = '~' ++ result = urllib.parse.parse_qs('a=1$b=2~c=3', separator='$') ++ self.assertEqual(result, {'a': ['1'], 'b': ['2~c=3']}) + + def test_urlencode_sequences(self): + # Other tests incidentally urlencode things; test non-covered cases: +diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py +index fa8827a9fa7..57b8fcf8bbd 100644 +--- a/Lib/urllib/parse.py ++++ b/Lib/urllib/parse.py +@@ -28,6 +28,7 @@ test_urlparse.py provides a good indicator of parsing behavior. + """ + + import re ++import os + import sys + import collections + +@@ -644,7 +645,8 @@ def unquote(string, encoding='utf-8', errors='replace'): + + + def parse_qs(qs, keep_blank_values=False, strict_parsing=False, +- encoding='utf-8', errors='replace', max_num_fields=None): ++ encoding='utf-8', errors='replace', max_num_fields=None, ++ separator=None): + """Parse a query given as a string argument. + + Arguments: +@@ -673,7 +675,8 @@ def parse_qs(qs, keep_blank_values=False, strict_parsing=False, + parsed_result = {} + pairs = parse_qsl(qs, keep_blank_values, strict_parsing, + encoding=encoding, errors=errors, +- max_num_fields=max_num_fields) ++ max_num_fields=max_num_fields, ++ separator=separator) + for name, value in pairs: + if name in parsed_result: + parsed_result[name].append(value) +@@ -681,9 +684,16 @@ def parse_qs(qs, keep_blank_values=False, strict_parsing=False, + parsed_result[name] = [value] + return parsed_result + ++class _QueryStringSeparatorWarning(RuntimeWarning): ++ """Warning for using default `separator` in parse_qs or parse_qsl""" ++ ++# The default "separator" for parse_qsl can be specified in a config file. ++# It's cached after first read. ++_QS_SEPARATOR_CONFIG_FILENAME = '/etc/python/urllib.cfg' ++_default_qs_separator = None + + def parse_qsl(qs, keep_blank_values=False, strict_parsing=False, +- encoding='utf-8', errors='replace', max_num_fields=None): ++ encoding='utf-8', errors='replace', max_num_fields=None, separator=None): + """Parse a query given as a string argument. + + Arguments: +@@ -710,15 +720,77 @@ def parse_qsl(qs, keep_blank_values=False, strict_parsing=False, + """ + qs, _coerce_result = _coerce_args(qs) + ++ if isinstance(separator, bytes): ++ separator = separator.decode('ascii') ++ ++ if (not separator or (not isinstance(separator, (str, bytes)))) and separator is not None: ++ raise ValueError("Separator must be of type string or bytes.") ++ ++ # Used when both "&" and ";" act as separators. (Need a non-string value.) ++ _legacy = object() ++ ++ if separator is None: ++ global _default_qs_separator ++ separator = _default_qs_separator ++ envvar_name = 'PYTHON_URLLIB_QS_SEPARATOR' ++ if separator is None: ++ # Set default separator from environment variable ++ separator = os.environ.get(envvar_name) ++ config_source = 'environment variable' ++ if separator is None: ++ # Set default separator from the configuration file ++ try: ++ file = open(_QS_SEPARATOR_CONFIG_FILENAME) ++ except FileNotFoundError: ++ pass ++ else: ++ with file: ++ import configparser ++ config = configparser.ConfigParser( ++ interpolation=None, ++ comment_prefixes=('#', ), ++ ) ++ config.read_file(file) ++ separator = config.get('parse_qs', envvar_name, fallback=None) ++ _default_qs_separator = separator ++ config_source = _QS_SEPARATOR_CONFIG_FILENAME ++ if separator is None: ++ # The default is '&', but warn if not specified explicitly ++ if ';' in qs: ++ from warnings import warn ++ warn("The default separator of urllib.parse.parse_qsl and " ++ + "parse_qs was changed to '&' to avoid a web cache " ++ + "poisoning issue (CVE-2021-23336). " ++ + "By default, semicolons no longer act as query field " ++ + "separators. " ++ + "See https://access.redhat.com/articles/5860431 for " ++ + "more details.", ++ _QueryStringSeparatorWarning, stacklevel=2) ++ separator = '&' ++ elif separator == 'legacy': ++ separator = _legacy ++ elif len(separator) != 1: ++ raise ValueError( ++ f'{envvar_name} (from {config_source}) must contain ' ++ + '1 character, or "legacy". See ' ++ + 'https://access.redhat.com/articles/5860431 for more details.' ++ ) ++ + # If max_num_fields is defined then check that the number of fields + # is less than max_num_fields. This prevents a memory exhaustion DOS + # attack via post bodies with many fields. + if max_num_fields is not None: +- num_fields = 1 + qs.count('&') + qs.count(';') ++ if separator is _legacy: ++ num_fields = 1 + qs.count('&') + qs.count(';') ++ else: ++ num_fields = 1 + qs.count(separator) + if max_num_fields < num_fields: + raise ValueError('Max number of fields exceeded') + +- pairs = [s2 for s1 in qs.split('&') for s2 in s1.split(';')] ++ if separator is _legacy: ++ pairs = [s2 for s1 in qs.split('&') for s2 in s1.split(';')] ++ else: ++ pairs = [s1 for s1 in qs.split(separator)] + r = [] + for name_value in pairs: + if not name_value and not strict_parsing: +diff --git a/Misc/NEWS.d/next/Security/2021-02-14-15-59-16.bpo-42967.YApqDS.rst b/Misc/NEWS.d/next/Security/2021-02-14-15-59-16.bpo-42967.YApqDS.rst +new file mode 100644 +index 00000000000..bc82c963067 +--- /dev/null ++++ b/Misc/NEWS.d/next/Security/2021-02-14-15-59-16.bpo-42967.YApqDS.rst +@@ -0,0 +1 @@ ++Make it possible to fix web cache poisoning vulnerability by allowing the user to choose a custom separator query args. diff --git a/SPECS/python3.spec b/SPECS/python3.spec index 9d0b8b7..1f4699d 100644 --- a/SPECS/python3.spec +++ b/SPECS/python3.spec @@ -14,7 +14,7 @@ URL: https://www.python.org/ # WARNING When rebasing to a new Python version, # remember to update the python3-docs package as well Version: %{pybasever}.8 -Release: 36%{?dist} +Release: 37%{?dist} License: Python @@ -584,6 +584,13 @@ Patch356: 00356-k_and_a_options_for_pathfix.patch # Main BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1918168 Patch357: 00357-CVE-2021-3177.patch +# 00359 # +# CVE-2021-23336 python: Web Cache Poisoning via urllib.parse.parse_qsl and +# urllib.parse.parse_qs by using a semicolon in query parameters +# Upstream: https://bugs.python.org/issue42967 +# Main BZ: https://bugzilla.redhat.com/show_bug.cgi?id=1928904 +Patch359: 00359-CVE-2021-23336.patch + # (New patches go here ^^^) # # When adding new patches to "python" and "python3" in Fedora, EL, etc., @@ -910,6 +917,7 @@ git apply %{PATCH351} %patch355 -p1 %patch356 -p1 %patch357 -p1 +%patch359 -p1 # Remove files that should be generated by the build # (This is after patching, so that we can use patches directly from upstream) @@ -1835,6 +1843,10 @@ fi # ====================================================== %changelog +* Thu Mar 04 2021 Petr Viktorin - 3.6.8-37 +- Fix for CVE-2021-23336 +Resolves: rhbz#1928904 + * Fri Jan 22 2021 Lumír Balhar - 3.6.8-36 - Fix for CVE-2021-3177 Resolves: rhbz#1918168