gh-74616: Raise ValueError in case of null character in input prompt (GH-1738)

If the input prompt to the builtin input function on terminal has any null
character, then raise ValueError instead of silently truncating it.

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 7a96251..960bca0 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -2262,6 +2262,11 @@ builtin_input_impl(PyObject *module, PyObject *prompt)
                 goto _readline_errors;
             assert(PyBytes_Check(po));
             promptstr = PyBytes_AS_STRING(po);
+            if ((Py_ssize_t)strlen(promptstr) != PyBytes_GET_SIZE(po)) {
+                PyErr_SetString(PyExc_ValueError,
+                        "input: prompt string cannot contain null characters");
+                goto _readline_errors;
+            }
         }
         else {
             po = NULL;