1 files changed, 6 insertions, 0 deletions
diff --git a/Modules/readline.c b/Modules/readline.c
index 35655c7..7d1f703 100644
--- a/Modules/readline.c
+++ b/Modules/readline.c
@@ -351,6 +351,12 @@ readline_append_history_file_impl(PyObject *module, int nelements,
                                   PyObject *filename_obj)
 /*[clinic end generated code: output=5df06fc9da56e4e4 input=784b774db3a4b7c5]*/
 {
+    if (nelements < 0)
+    {
+        PyErr_SetString(PyExc_ValueError, "nelements must be positive");
+        return NULL;
+    }
+
     PyObject *filename_bytes;
     const char *filename;
     int err;