Make the various iterators' "setstate" sliently and consistently clip the

index.  This avoids the possibility of setting an iterator to an invalid
state.

1 files changed, 7 insertions, 3 deletions

diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 03007531bd..4085d22b71 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -14420,9 +14420,13 @@ unicodeiter_setstate(unicodeiterobject *it, PyObject *state)
     Py_ssize_t index = PyLong_AsSsize_t(state);
     if (index == -1 && PyErr_Occurred())
         return NULL;
-    if (index < 0)
-        index = 0;
-    it->it_index = index;
+    if (it->it_seq != NULL) {
+        if (index < 0)
+            index = 0;
+        else if (index > PyUnicode_GET_LENGTH(it->it_seq))
+            index = PyUnicode_GET_LENGTH(it->it_seq); /* iterator truncated */
+        it->it_index = index;
+    }
     Py_RETURN_NONE;
 }