From: Benjamin Peterson <benjamin@python.org>
Date: Sat, 25 Apr 2009 01:37:40 +0000 (+0000)
Subject: Merged revisions 71862 via svnmerge from
X-Git-Tag: 3.0~182
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0348681494fc396fe740d39181531bf0521c0042;p=thirdparty%2FPython%2Fcpython.git

Merged revisions 71862 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

................
  r71862 | benjamin.peterson | 2009-04-24 20:08:45 -0500 (Fri, 24 Apr 2009) | 9 lines

  Merged revisions 71860 via svnmerge from
  svn+ssh://pythondev@svn.python.org/python/trunk

  ........
    r71860 | benjamin.peterson | 2009-04-24 19:41:22 -0500 (Fri, 24 Apr 2009) | 1 line

    fix a segfault when setting __class__ in __del__ #5283
  ........
................
---

diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 8b27af050b1d..073305f5b9c6 100644
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -2712,6 +2712,16 @@ order (MRO) for bases """
                     continue
                 cant(cls(), cls2)
 
+        # Issue5283: when __class__ changes in __del__, the wrong
+        # type gets DECREF'd.
+        class O(object):
+            pass
+        class A(object):
+            def __del__(self):
+                self.__class__ = O
+        l = [A() for x in range(100)]
+        del l
+
     def test_set_dict(self):
         # Testing __dict__ assignment...
         class C(object): pass
diff --git a/Misc/NEWS b/Misc/NEWS
index f867d84700d7..8c6e6302d7df 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -16,6 +16,8 @@ Core and Builtins
   imp.find_module() were converted to UTF-8 while the path is
   converted to the default filesystem encoding, causing nonsense.
 
+- Issue #5283: Setting __class__ in __del__ caused a segfault.
+
 - Issue #5759: float() didn't call __float__ on str subclasses.
 
 - Issue #5787: object.__getattribute__(some_type, "__bases__") segfaulted on
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index e7f68d693ede..fa6250b18f6c 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -877,6 +877,9 @@ subtype_dealloc(PyObject *self)
 			assert(base);
 		}
 
+		/* Extract the type again; tp_del may have changed it */
+		type = Py_TYPE(self);
+
 		/* Call the base tp_dealloc() */
 		assert(basedealloc);
 		basedealloc(self);
@@ -958,6 +961,9 @@ subtype_dealloc(PyObject *self)
 		}
 	}
 
+	/* Extract the type again; tp_del may have changed it */
+	type = Py_TYPE(self);
+
 	/* Call the base tp_dealloc(); first retrack self if
 	 * basedealloc knows about gc.
 	 */