Check the type of values returned by __int__, __float__, __long__,

__oct__, and __hex__.  Raise TypeError if an invalid type is
returned.  Note that PyNumber_Int and PyNumber_Long can still
return ints or longs.  Fixes SF bug #966618.

2 files changed, 33 insertions, 12 deletions

diff --git a/Objects/abstract.c b/Objects/abstract.c
index 01e3e4c..bc36c6f 100644
--- a/Objects/abstract.c
+++ b/Objects/abstract.c
@@ -965,8 +965,17 @@ PyNumber_Int(PyObject *o)
 					 10);
 #endif
 	m = o->ob_type->tp_as_number;
-	if (m && m->nb_int)
-		return m->nb_int(o);
+	if (m && m->nb_int) {
+		PyObject *res = m->nb_int(o);
+		if (res && (!PyInt_Check(res) && !PyLong_Check(res))) {
+			PyErr_Format(PyExc_TypeError,
+				     "__int__ returned non-int (type %.200s)",
+				     res->ob_type->tp_name);
+			Py_DECREF(res);
+			return NULL;
+		}
+		return res;
+	}
 	if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
 		return int_from_string((char*)buffer, buffer_len);
 
@@ -1022,8 +1031,17 @@ PyNumber_Long(PyObject *o)
 					  10);
 #endif
 	m = o->ob_type->tp_as_number;
-	if (m && m->nb_long)
-		return m->nb_long(o);
+	if (m && m->nb_long) {
+		PyObject *res = m->nb_long(o);
+		if (res && (!PyInt_Check(res) && !PyLong_Check(res))) {
+			PyErr_Format(PyExc_TypeError,
+				     "__long__ returned non-long (type %.200s)",
+				     res->ob_type->tp_name);
+			Py_DECREF(res);
+			return NULL;
+		}
+		return res;
+	}
 	if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
 		return long_from_string(buffer, buffer_len);
 
@@ -1047,8 +1065,17 @@ PyNumber_Float(PyObject *o)
 	}
 	if (!PyString_Check(o)) {
 		m = o->ob_type->tp_as_number;
-		if (m && m->nb_float)
-			return m->nb_float(o);
+		if (m && m->nb_float) {
+			PyObject *res = m->nb_float(o);
+			if (res && !PyFloat_Check(res)) {
+				PyErr_Format(PyExc_TypeError,
+			          "__float__ returned non-float (type %.200s)",
+			          res->ob_type->tp_name);
+				Py_DECREF(res);
+				return NULL;
+			}
+			return res;
+		}
 	}
 	return PyFloat_FromString(o, NULL);
 }
diff --git a/Objects/intobject.c b/Objects/intobject.c
index bdf7da3..f52ef07 100644
--- a/Objects/intobject.c
+++ b/Objects/intobject.c
@@ -948,12 +948,6 @@ int_subtype_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 	if (tmp == NULL)
 		return NULL;
 	if (!PyInt_Check(tmp)) {
-		if (!PyLong_Check(tmp)) {
-			PyErr_SetString(PyExc_ValueError,
-					"value can't be converted to int");
-			Py_DECREF(tmp);
-			return NULL;
-		}
 		ival = PyLong_AsLong(tmp);
 		if (ival == -1 && PyErr_Occurred()) {
 			Py_DECREF(tmp);