[Patches] PyObject_GetAttr/PyObject_SetAttr core dumps if given non-string names
Gisle Aas
gisle@ActiveState.com
22 Jun 2000 22:38:58 +0200
"M.-A. Lemburg" <mal@lemburg.com> writes:
> > Index: Objects/object.c
> > ===================================================================
> > RCS file: /cvsroot/python/python/dist/src/Objects/object.c,v
> > retrieving revision 2.71
> > diff -u -p -u -r2.71 object.c
> > --- Objects/object.c 2000/06/09 16:20:39 2.71
> > +++ Objects/object.c 2000/06/22 19:27:51
> > @@ -600,8 +600,12 @@ PyObject_GetAttr(v, name)
> > {
> > if (v->ob_type->tp_getattro != NULL)
> > return (*v->ob_type->tp_getattro)(v, name);
> > - else
> > + else if (PyString_Check(name))
> > return PyObject_GetAttrString(v, PyString_AsString(name));
> > + else {
> > + PyErr_SetString(PyExc_TypeError,
> > + "attribute name must be string");
> > + }
> > }
>
> Hmm, I think it would be more generic to add a NULL
> check to PyObject_GetAttrString() (PyString_AsString() returns
> NULL in case name is not a string object).
Ok. But it also set up the exception to be BadInternalCall() which
does not feel right :-)
I also forgot to "return NULL" here.
> > int
> > @@ -626,12 +630,18 @@ PyObject_SetAttr(v, name, value)
> > {
> > int err;
> > Py_INCREF(name);
> > - PyString_InternInPlace(&name);
> > if (v->ob_type->tp_setattro != NULL)
> > err = (*v->ob_type->tp_setattro)(v, name, value);
> > - else
> > + else if (PyString_Check(name)) {
> > + PyString_InternInPlace(&name);
> > err = PyObject_SetAttrString(
> > v, PyString_AsString(name), value);
> > + }
> > + else {
> > + PyErr_SetString(PyExc_TypeError,
> > + "attribute name must be string");
> > + err = -1;
> > + }
>
> Here, I think you ought to move the string test just before
> the interning call.
But you still want to be able to pass non-string objects to
v->ob_type->tp_setattro I guess. Anyway, an alternative patch is
included here.
Thanks for the quick feedback!
Regards,
Gisle
Index: Objects/object.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/object.c,v
retrieving revision 2.71
diff -u -p -u -r2.71 object.c
--- Objects/object.c 2000/06/09 16:20:39 2.71
+++ Objects/object.c 2000/06/22 20:37:21
@@ -598,10 +598,17 @@ PyObject_GetAttr(v, name)
PyObject *v;
PyObject *name;
{
+ char *name_str;
if (v->ob_type->tp_getattro != NULL)
return (*v->ob_type->tp_getattro)(v, name);
- else
- return PyObject_GetAttrString(v, PyString_AsString(name));
+
+ name_str = PyString_AsString(name);
+ if (name_str == NULL) {
+ PyErr_SetString(PyExc_TypeError,
+ "attribute name must be string");
+ return NULL;
+ }
+ return PyObject_GetAttrString(v, name_str);
}
int
@@ -625,13 +632,23 @@ PyObject_SetAttr(v, name, value)
PyObject *value;
{
int err;
+ int name_is_string = 0;
Py_INCREF(name);
- PyString_InternInPlace(&name);
+ if (PyString_Check(name)) {
+ PyString_InternInPlace(&name);
+ name_is_string = 1;
+ }
if (v->ob_type->tp_setattro != NULL)
err = (*v->ob_type->tp_setattro)(v, name, value);
- else
+ else if (name_is_string) {
err = PyObject_SetAttrString(
v, PyString_AsString(name), value);
+ }
+ else {
+ PyErr_SetString(PyExc_TypeError,
+ "attribute name must be string");
+ err = -1;
+ }
Py_DECREF(name);
return err;
}
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