python3: fix CVE-2020-26116

(From OE-Core rev: 2f607a61a820bfbc369f779c3161a339f088d04f) Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com> Signed-off-by: Steve Sakoman <steve@sakoman.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
2026-02-06 08:48:45 +01:00 · 2020-10-19 20:59:56 +08:00
parent 781175443f
commit 002113701a
2 changed files with 105 additions and 0 deletions
--- a/meta/recipes-devtools/python/python3/CVE-2020-26116.patch
+++ b/meta/recipes-devtools/python/python3/CVE-2020-26116.patch
@@ -0,0 +1,104 @@
+From 668d321476d974c4f51476b33aaca870272523bf Mon Sep 17 00:00:00 2001
+From: "Miss Islington (bot)"
+ <31488909+miss-islington@users.noreply.github.com>
+Date: Sat, 18 Jul 2020 13:39:12 -0700
+Subject: [PATCH] bpo-39603: Prevent header injection in http methods
+ (GH-18485)
+
+reject control chars in http method in http.client.putrequest to prevent http header injection
+(cherry picked from commit 8ca8a2e8fb068863c1138f07e3098478ef8be12e)
+
+Co-authored-by: AMIR <31338382+amiremohamadi@users.noreply.github.com>
+
+Upstream-Status: Backport [https://github.com/python/cpython/commit/668d321476d974c4f51476b33aaca870272523bf]
+CVE: CVE-2020-26116
+Signed-off-by: Chee Yang Lee <chee.yang.lee@intel.com>
+
+---
+ Lib/http/client.py                            | 15 +++++++++++++
+ Lib/test/test_httplib.py                      | 22 +++++++++++++++++++
+ .../2020-02-12-14-17-39.bpo-39603.Gt3RSg.rst  |  2 ++
+ 3 files changed, 39 insertions(+)
+ create mode 100644 Misc/NEWS.d/next/Security/2020-02-12-14-17-39.bpo-39603.Gt3RSg.rst
+
+diff --git a/Lib/http/client.py b/Lib/http/client.py
+index 019380a720318..c2ad0471bfee5 100644
+--- a/Lib/http/client.py
+++ b/Lib/http/client.py
+@@ -147,6 +147,10 @@
+ #  _is_allowed_url_pchars_re = re.compile(r"^[/!$&'()*+,;=:@%a-zA-Z0-9._~-]+$")
+ # We are more lenient for assumed real world compatibility purposes.
+ 
+# These characters are not allowed within HTTP method names
+# to prevent http header injection.
+_contains_disallowed_method_pchar_re = re.compile('[\x00-\x1f]')
+
+ # We always set the Content-Length header for these methods because some
+ # servers will otherwise respond with a 411
+ _METHODS_EXPECTING_BODY = {'PATCH', 'POST', 'PUT'}
+@@ -1087,6 +1091,8 @@ def putrequest(self, method, url, skip_host=False,
+         else:
+             raise CannotSendRequest(self.__state)
+ 
+        self._validate_method(method)
+
+         # Save the method for use later in the response phase
+         self._method = method
+ 
+@@ -1177,6 +1183,15 @@ def _encode_request(self, request):
+         # ASCII also helps prevent CVE-2019-9740.
+         return request.encode('ascii')
+ 
+    def _validate_method(self, method):
+        """Validate a method name for putrequest."""
+        # prevent http header injection
+        match = _contains_disallowed_method_pchar_re.search(method)
+        if match:
+            raise ValueError(
+                    f"method can't contain control characters. {method!r} "
+                    f"(found at least {match.group()!r})")
+
+     def _validate_path(self, url):
+         """Validate a url for putrequest."""
+         # Prevent CVE-2019-9740.
+diff --git a/Lib/test/test_httplib.py b/Lib/test/test_httplib.py
+index 8f0e27a1fb836..5a5fcecbc9c15 100644
+--- a/Lib/test/test_httplib.py
+++ b/Lib/test/test_httplib.py
+@@ -364,6 +364,28 @@ def test_headers_debuglevel(self):
+         self.assertEqual(lines[3], "header: Second: val2")
+ 
+ 
+class HttpMethodTests(TestCase):
+    def test_invalid_method_names(self):
+        methods = (
+            'GET\r',
+            'POST\n',
+            'PUT\n\r',
+            'POST\nValue',
+            'POST\nHOST:abc',
+            'GET\nrHost:abc\n',
+            'POST\rRemainder:\r',
+            'GET\rHOST:\n',
+            '\nPUT'
+        )
+
+        for method in methods:
+            with self.assertRaisesRegex(
+                    ValueError, "method can't contain control characters"):
+                conn = client.HTTPConnection('example.com')
+                conn.sock = FakeSocket(None)
+                conn.request(method=method, url="/")
+
+
+ class TransferEncodingTest(TestCase):
+     expected_body = b"It's just a flesh wound"
+ 
+diff --git a/Misc/NEWS.d/next/Security/2020-02-12-14-17-39.bpo-39603.Gt3RSg.rst b/Misc/NEWS.d/next/Security/2020-02-12-14-17-39.bpo-39603.Gt3RSg.rst
+new file mode 100644
+index 0000000000000..990affc3edd9d
+--- /dev/null
+++ b/Misc/NEWS.d/next/Security/2020-02-12-14-17-39.bpo-39603.Gt3RSg.rst
+@@ -0,0 +1,2 @@
+Prevent http header injection by rejecting control characters in
+http.client.putrequest(...).