Issue #15229: An OSError subclass whose __init__ doesn't call back

OSError.__init__ could produce incomplete instances, leading to crashes
when calling str() on them.

1 files changed, 6 insertions, 0 deletions

diff --git a/Objects/exceptions.c b/Objects/exceptions.c
index f706698499..5c85f10444 100644
--- a/Objects/exceptions.c
+++ b/Objects/exceptions.c
@@ -834,6 +834,7 @@ oserror_init(PyOSErrorObject *self, PyObject **p_args,
 #endif
 
     /* Steals the reference to args */
+    Py_CLEAR(self->args);
     self->args = args;
     args = NULL;
 
@@ -916,6 +917,11 @@ OSError_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
             ))
             goto error;
     }
+    else {
+        self->args = PyTuple_New(0);
+        if (self->args == NULL)
+            goto error;
+    }
 
     return (PyObject *) self;