gh-142754: Ensure that Element & Attr instances have the ownerDocument attribute...

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>
Origin: backport, https://github.com/python/cpython/commit/1cc7551b3f9f71efbc88d96dce90f82de98b2454
Debian-Bug: https://bugs.debian.org/1122875

Gbp-Pq: Name CVE-2025-12084-2.patch

diff --git a/Lib/test/test_minidom.py b/Lib/test/test_minidom.py
index 840a3f5a11224a232bcdeb596b2c86b60f26a030..0868ff4d579e447599063755cc16c8805d5eb752 100644 (file)
--- a/Lib/test/test_minidom.py
+++ b/Lib/test/test_minidom.py
@@ -10,7 +10,7 @@ import unittest
 import pyexpat
 import xml.dom.minidom
 
-from xml.dom.minidom import parse, Node, Document, parseString
+from xml.dom.minidom import parse, Attr, Node, Document, Element, parseString
 from xml.dom.minidom import getDOMImplementation
 from xml.parsers.expat import ExpatError
 
@@ -181,6 +181,14 @@ class MinidomTest(unittest.TestCase):
         # This example used to take at least 30 seconds.
         self.assertLess(end - start, 10)
 
+    def testSetAttributeNodeWithoutOwnerDocument(self):
+        # regression test for gh-142754
+        elem = Element("test")
+        attr = Attr("id")
+        attr.value = "test-id"
+        elem.setAttributeNode(attr)
+        self.assertEqual(elem.getAttribute("id"), "test-id")
+
     def testAppendChildFragment(self):
         dom, orig, c1, c2, c3, frag = self._create_fragment_test_nodes()
         dom.documentElement.appendChild(frag)

diff --git a/Lib/xml/dom/minidom.py b/Lib/xml/dom/minidom.py
index 3a9129596280bcb3e334c8184574011b3d9bd10d..e4e8b42996bae0bd2d8f06759db40da6bef389f8 100644 (file)
--- a/Lib/xml/dom/minidom.py
+++ b/Lib/xml/dom/minidom.py
@@ -348,6 +348,7 @@ class Attr(Node):
     def __init__(self, qName, namespaceURI=EMPTY_NAMESPACE, localName=None,
                  prefix=None):
         self.ownerElement = None
+        self.ownerDocument = None
         self._name = qName
         self.namespaceURI = namespaceURI
         self._prefix = prefix
@@ -671,6 +672,7 @@ class Element(Node):
 
     def __init__(self, tagName, namespaceURI=EMPTY_NAMESPACE, prefix=None,
                  localName=None):
+        self.ownerDocument = None
         self.parentNode = None
         self.tagName = self.nodeName = tagName
         self.prefix = prefix

diff --git a/Misc/NEWS.d/next/Library/2025-12-16-11-55-55.gh-issue-142754.xuCrt3.rst b/Misc/NEWS.d/next/Library/2025-12-16-11-55-55.gh-issue-142754.xuCrt3.rst
new file mode 100644 (file)
index 0000000..d4e158c
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-12-16-11-55-55.gh-issue-142754.xuCrt3.rst
@@ -0,0 +1,4 @@
+Add the *ownerDocument* attribute to :mod:`xml.dom.minidom` elements and attributes
+created by directly instantiating the ``Element`` or ``Attr`` class. Note that
+this way of creating nodes is not supported; creator functions like
+:py:meth:`xml.dom.Document.documentElement` should be used instead.