From: Serhiy Storchaka <storchaka@gmail.com>
Date: Sat, 17 Feb 2024 21:43:59 +0000 (+0200)
Subject: [3.12] gh-115618: Remove improper Py_XDECREFs in property methods (GH-115619) (GH... 
X-Git-Tag: v3.12.3~252
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b9d1efa696d026a8b481eb77ded87e641a9f76ad;p=thirdparty%2FPython%2Fcpython.git

[3.12] gh-115618: Remove improper Py_XDECREFs in property methods (GH-115619) (GH-115620)

(cherry picked from commit 090dd21ab9379d6a2a6923d6cbab697355fb7165)
---

diff --git a/Lib/test/test_property.py b/Lib/test/test_property.py
index 3b2af50f8361..4de2bb3781f8 100644
--- a/Lib/test/test_property.py
+++ b/Lib/test/test_property.py
@@ -183,6 +183,24 @@ class PropertyTests(unittest.TestCase):
             fake_prop.__init__('fget', 'fset', 'fdel', 'doc')
         self.assertAlmostEqual(gettotalrefcount() - refs_before, 0, delta=10)
 
+    @support.refcount_test
+    def test_gh_115618(self):
+        # Py_XDECREF() was improperly called for None argument
+        # in property methods.
+        gettotalrefcount = support.get_attribute(sys, 'gettotalrefcount')
+        prop = property()
+        refs_before = gettotalrefcount()
+        for i in range(100):
+            prop = prop.getter(None)
+        self.assertIsNone(prop.fget)
+        for i in range(100):
+            prop = prop.setter(None)
+        self.assertIsNone(prop.fset)
+        for i in range(100):
+            prop = prop.deleter(None)
+        self.assertIsNone(prop.fdel)
+        self.assertAlmostEqual(gettotalrefcount() - refs_before, 0, delta=10)
+
     @unittest.skipIf(sys.flags.optimize >= 2,
                      "Docstrings are omitted with -O2 and above")
     def test_class_property(self):
diff --git a/Misc/NEWS.d/next/Library/2024-02-17-18-47-12.gh-issue-115618.napiNp.rst b/Misc/NEWS.d/next/Library/2024-02-17-18-47-12.gh-issue-115618.napiNp.rst
new file mode 100644
index 000000000000..cb4b147d5dc6
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-02-17-18-47-12.gh-issue-115618.napiNp.rst
@@ -0,0 +1,3 @@
+Fix improper decreasing the reference count for ``None`` argument in
+:class:`property` methods :meth:`~property.getter`, :meth:`~property.setter`
+and :meth:`~property.deleter`.
diff --git a/Objects/descrobject.c b/Objects/descrobject.c
index 72ac47039492..18876fd2b883 100644
--- a/Objects/descrobject.c
+++ b/Objects/descrobject.c
@@ -1697,15 +1697,12 @@ property_copy(PyObject *old, PyObject *get, PyObject *set, PyObject *del)
         return NULL;
 
     if (get == NULL || get == Py_None) {
-        Py_XDECREF(get);
         get = pold->prop_get ? pold->prop_get : Py_None;
     }
     if (set == NULL || set == Py_None) {
-        Py_XDECREF(set);
         set = pold->prop_set ? pold->prop_set : Py_None;
     }
     if (del == NULL || del == Py_None) {
-        Py_XDECREF(del);
         del = pold->prop_del ? pold->prop_del : Py_None;
     }
     if (pold->getter_doc && get != Py_None) {