Merge

Lib/inspect.py

@@ -1186,10 +1186,11 @@ def getattr_static(obj, attr, default=_sentinel):
     if obj is klass:
         # for types we check the metaclass too
         for entry in _static_getmro(type(klass)):
-            try:
-                return entry.__dict__[attr]
-            except KeyError:
-                pass
+            if _shadowed_dict(type(entry)) is _sentinel:
+                try:
+                    return entry.__dict__[attr]
+                except KeyError:
+                    pass
     if default is not _sentinel:
         return default
     raise AttributeError(attr)

Lib/test/test_inspect.py

@@ -1088,6 +1088,23 @@ class TestGetattrStatic(unittest.TestCase):
         self.assertIsNot(inspect.getattr_static(sys, "version", sentinel),
                          sentinel)
 
+    def test_metaclass_with_metaclass_with_dict_as_property(self):
+        class MetaMeta(type):
+            @property
+            def __dict__(self):
+                self.executed = True
+                return dict(spam=42)
+
+        class Meta(type, metaclass=MetaMeta):
+            executed = False
+
+        class Thing(metaclass=Meta):
+            pass
+
+        with self.assertRaises(AttributeError):
+            inspect.getattr_static(Thing, "spam")
+        self.assertFalse(Thing.executed)
+
 class TestGetGeneratorState(unittest.TestCase):
 
     def setUp(self):

Misc/NEWS

@@ -422,6 +422,9 @@ Library
 - Issue #13620: Support for Chrome browser in webbrowser.py Patch contributed
   by Arnaud Calmettes.
 
+- Issue #11829: Fix code execution holes in inspect.getattr_static for
+  metaclasses with metaclasses. Patch by Andreas Stührk.
+
 - Issue #12708: Add starmap() and starmap_async() methods (similar to
   itertools.starmap()) to multiprocessing.Pool.  Patch by Hynek Schlawack.