Backport 43022:

Fix and test (manually w/xx module) passing NULLs to PyObject_Str() and
PyObject_Unicode().  This problem was originally reported from Coverity
and addresses mail on python-dev "checkin r43015".

This inlines the conversion of the string to unicode and cleans
up/simplifies some code at the end of the PyObject_Unicode().

We really need a complete C API test module for all public APIs
and passing good and bad parameter values.

1 files changed, 7 insertions, 5 deletions

diff --git a/Objects/object.c b/Objects/object.c
index 87aa475..7dbd554 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -373,9 +373,15 @@ PyObject *
 PyObject_Unicode(PyObject *v)
 {
 	PyObject *res;
+	PyObject *str;
 
 	if (v == NULL) {
 		res = PyString_FromString("<NULL>");
+		if (res == NULL)
+			return NULL;
+		str = PyUnicode_FromEncodedObject(res, NULL, "strict");
+		Py_DECREF(res);
+		return str;
 	} else if (PyUnicode_CheckExact(v)) {
 		Py_INCREF(v);
 		return v;
@@ -418,13 +424,9 @@ PyObject_Unicode(PyObject *v)
 	if (res == NULL)
 		return NULL;
 	if (!PyUnicode_Check(res)) {
-		PyObject *str;
 		str = PyUnicode_FromEncodedObject(res, NULL, "strict");
 		Py_DECREF(res);
-		if (str)
-			res = str;
-		else
-		    	return NULL;
+		res = str;
 	}
 	return res;
 }