Patch CVE-2024-49767 in python-werkzeug (#10949)

Co-authored-by: Suresh Thelkar <sthelkar@microsoft.com>

Author: suresh-thelkar

SPECS/python-werkzeug/CVE-2024-49767.patch

@@ -0,0 +1,85 @@
+From 65c8b89ca07543209451a646348bbadb3ca2a4d0 Mon Sep 17 00:00:00 2001
+From: David Lord <davidism@gmail.com>
+Date: Fri, 25 Oct 2024 06:46:50 -0700
+Subject: [PATCH] apply max_form_memory_size another level up in the parser
+
+Upstream patch details are given below.
+https://github.com/pallets/werkzeug/commit/50cfeebcb0727e18cc52ffbeb125f4a66551179b#diff-ff3c479edefad986d2fe6fe7ead575a46b086e3bbcf0ccc86d85efc4a4c63c79
+---
+ src/werkzeug/formparser.py       | 11 +++++++++++
+ src/werkzeug/sansio/multipart.py |  2 ++
+ tests/test_formparser.py         | 12 ++++++++++++
+ 3 files changed, 25 insertions(+)
+
+diff --git a/src/werkzeug/formparser.py b/src/werkzeug/formparser.py
+index 25ef0d6..a5838e4 100644
+--- a/src/werkzeug/formparser.py
++++ b/src/werkzeug/formparser.py
+@@ -480,6 +480,7 @@ class MultiPartParser:
+         self, stream: t.IO[bytes], boundary: bytes, content_length: int | None
+     ) -> tuple[MultiDict, MultiDict]:
+         current_part: Field | File
++        field_size: int | None = None
+         container: t.IO[bytes] | list[bytes]
+         _write: t.Callable[[bytes], t.Any]
+ 
+@@ -498,13 +499,23 @@ class MultiPartParser:
+             while not isinstance(event, (Epilogue, NeedData)):
+                 if isinstance(event, Field):
+                     current_part = event
++                    field_size = 0
+                     container = []
+                     _write = container.append
+                 elif isinstance(event, File):
+                     current_part = event
++                    field_size = None
+                     container = self.start_file_streaming(event, content_length)
+                     _write = container.write
+                 elif isinstance(event, Data):
++                    if self.max_form_memory_size is not None and field_size is not None:
++                        # Ensure that accumulated data events do not exceed limit.
++                        # Also checked within single event in MultipartDecoder.
++                        field_size += len(event.data)
++
++                        if field_size > self.max_form_memory_size:
++                            raise RequestEntityTooLarge()
++
+                     _write(event.data)
+                     if not event.more_data:
+                         if isinstance(current_part, Field):
+diff --git a/src/werkzeug/sansio/multipart.py b/src/werkzeug/sansio/multipart.py
+index fc87353..731be03 100644
+--- a/src/werkzeug/sansio/multipart.py
++++ b/src/werkzeug/sansio/multipart.py
+@@ -140,6 +140,8 @@ class MultipartDecoder:
+             self.max_form_memory_size is not None
+             and len(self.buffer) + len(data) > self.max_form_memory_size
+         ):
++            # Ensure that data within single event does not exceed limit.
++            # Also checked across accumulated events in MultiPartParser.
+             raise RequestEntityTooLarge()
+         else:
+             self.buffer.extend(data)
+diff --git a/tests/test_formparser.py b/tests/test_formparser.py
+index 1dcb167..d8e18e0 100644
+--- a/tests/test_formparser.py
++++ b/tests/test_formparser.py
+@@ -448,3 +448,15 @@ class TestMultiPartParser:
+         ) as request:
+             assert request.files["rfc2231"].filename == "a b c d e f.txt"
+             assert request.files["rfc2231"].read() == b"file contents"
++
++
++def test_multipart_max_form_memory_size() -> None:
++    """max_form_memory_size is tracked across multiple data events."""
++    data = b"--bound\r\nContent-Disposition: form-field; name=a\r\n\r\n"
++    data += b"a" * 15 + b"\r\n--bound--"
++    # The buffer size is less than the max size, so multiple data events will be
++    # returned. The field size is greater than the max.
++    parser = formparser.MultiPartParser(max_form_memory_size=10, buffer_size=5)
++
++    with pytest.raises(RequestEntityTooLarge):
++        parser.parse(io.BytesIO(data), b"bound", None)
+-- 
+2.34.1
+

SPECS/python-werkzeug/python-werkzeug.spec

@@ -1,7 +1,7 @@
 Summary:        The Swiss Army knife of Python web development
 Name:           python-werkzeug
 Version:        2.3.7
-Release:        2%{?dist}
+Release:        3%{?dist}
 License:        BSD
 Vendor:         Microsoft Corporation
 Distribution:   Mariner
@@ -19,6 +19,7 @@ Patch0:         0001-enable-tests-in-rpm-env.patch
 Patch1:         0002-disable-stat-test.patch
 Patch2:         CVE-2023-46136.patch
 Patch3:         CVE-2024-34069.patch
+Patch4:         CVE-2024-49767.patch
 BuildArch:      noarch
 
 %description
@@ -71,6 +72,9 @@ pip3 install -r requirements/tests.txt
 %license LICENSE.rst
 
 %changelog
+* Tue Nov 05 2024 Suresh Thelkar <sthelkar@microsoft.com> - 2.3.7-3
+- Patch CVE-2024-49767
+
 * Tue May 14 2024 Jonathan Behrens <jbehrens@microsoft.com> - 2.3.7-2
 - Patch CVE-2024-34069