PyObject_SetAttr() and PyObject_GetAttr() now also accept Unicode
objects for the attribute name. Unicode objects are converted to
a string using the default encoding before trying the lookup.
Note that previously it was allowed to pass arbitrary objects as
attribute name in case the tp_getattro/setattro slots were defined.
This patch fixes this by applying an explicit string check first:
all uses of these slots expect string objects and do not check
for the type resulting in a core dump. The tp_getattro/setattro
are still useful as optimization for lookups using interned
string objects though.
This patch fixes bug #113829.
diff --git a/Objects/object.c b/Objects/object.c
index 150f357..3323906 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -703,17 +703,31 @@
}
}
+/* Internal API needed by PyObject_GetAttr(): */
+extern
+PyObject *_PyUnicode_AsDefaultEncodedString(PyObject *unicode,
+ const char *errors);
+
PyObject *
PyObject_GetAttr(PyObject *v, PyObject *name)
{
- if (v->ob_type->tp_getattro != NULL)
- return (*v->ob_type->tp_getattro)(v, name);
+ /* The Unicode to string conversion is done here because the
+ existing tp_getattro slots expect a string object as name
+ and we wouldn't want to break those. */
+ if (PyUnicode_Check(name)) {
+ name = _PyUnicode_AsDefaultEncodedString(name, NULL);
+ if (name == NULL)
+ return NULL;
+ }
if (!PyString_Check(name)) {
PyErr_SetString(PyExc_TypeError,
"attribute name must be string");
return NULL;
}
+ if (v->ob_type->tp_getattro != NULL)
+ return (*v->ob_type->tp_getattro)(v, name);
+ else
return PyObject_GetAttrString(v, PyString_AS_STRING(name));
}
@@ -733,20 +747,32 @@
PyObject_SetAttr(PyObject *v, PyObject *name, PyObject *value)
{
int err;
- Py_INCREF(name);
- if (PyString_Check(name))
- PyString_InternInPlace(&name);
- if (v->ob_type->tp_setattro != NULL)
- err = (*v->ob_type->tp_setattro)(v, name, value);
- else if (PyString_Check(name)) {
- err = PyObject_SetAttrString(
- v, PyString_AS_STRING(name), value);
+
+ /* The Unicode to string conversion is done here because the
+ existing tp_setattro slots expect a string object as name
+ and we wouldn't want to break those. */
+ if (PyUnicode_Check(name)) {
+ name = PyUnicode_AsEncodedString(name, NULL, NULL);
+ if (name == NULL)
+ return -1;
}
- else {
+ else
+ Py_INCREF(name);
+
+ if (!PyString_Check(name)){
PyErr_SetString(PyExc_TypeError,
"attribute name must be string");
err = -1;
}
+ else {
+ PyString_InternInPlace(&name);
+ if (v->ob_type->tp_setattro != NULL)
+ err = (*v->ob_type->tp_setattro)(v, name, value);
+ else
+ err = PyObject_SetAttrString(v,
+ PyString_AS_STRING(name), value);
+ }
+
Py_DECREF(name);
return err;
}