bail in unicode error's __str__ methods if the objects are not properly initialized (closes #21134)

1 files changed, 12 insertions, 0 deletions

diff --git a/Objects/exceptions.c b/Objects/exceptions.c
index 0f86cfb..e165528 100644
--- a/Objects/exceptions.c
+++ b/Objects/exceptions.c
@@ -1648,6 +1648,10 @@ UnicodeEncodeError_str(PyObject *self)
     PyObject *reason_str = NULL;
     PyObject *encoding_str = NULL;
 
+    if (!uself->object)
+        /* Not properly initialized. */
+        return PyUnicode_FromString("");
+
     /* Get reason and encoding as strings, which they might not be if
        they've been modified after we were contructed. */
     reason_str = PyObject_Str(uself->reason);
@@ -1733,6 +1737,10 @@ UnicodeDecodeError_str(PyObject *self)
     PyObject *reason_str = NULL;
     PyObject *encoding_str = NULL;
 
+    if (!uself->object)
+        /* Not properly initialized. */
+        return PyUnicode_FromString("");
+
     /* Get reason and encoding as strings, which they might not be if
        they've been modified after we were contructed. */
     reason_str = PyObject_Str(uself->reason);
@@ -1830,6 +1838,10 @@ UnicodeTranslateError_str(PyObject *self)
     PyObject *result = NULL;
     PyObject *reason_str = NULL;
 
+    if (!uself->object)
+        /* Not properly initialized. */
+        return PyUnicode_FromString("");
+
     /* Get reason as a string, which it might not be if it's been
        modified after we were contructed. */
     reason_str = PyObject_Str(uself->reason);