Issue #15989: Fix several occurrences of integer overflow

when result of PyLong_AsLong() narrowed to int without checks.

This is a backport of changesets 13e2e44db99d and 525407d89277.

2 files changed, 3 insertions, 3 deletions

diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index ca25209305..8c1fabe360 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -244,7 +244,7 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
         return -1;
     }
 
-    fd = PyLong_AsLong(nameobj);
+    fd = _PyLong_AsInt(nameobj);
     if (fd < 0) {
         if (!PyErr_Occurred()) {
             PyErr_SetString(PyExc_ValueError,
@@ -382,7 +382,7 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
                 goto error;
             }
 
-            self->fd = PyLong_AsLong(fdobj);
+            self->fd = _PyLong_AsInt(fdobj);
             Py_DECREF(fdobj);
             if (self->fd == -1) {
                 goto error;
diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
index 83437d6add..a93049f3b5 100644
--- a/Modules/_io/textio.c
+++ b/Modules/_io/textio.c
@@ -881,7 +881,7 @@ textiowrapper_init(textio *self, PyObject *args, PyObject *kwds)
             }
         }
         else {
-            int fd = (int) PyLong_AsLong(fileno);
+            int fd = _PyLong_AsInt(fileno);
             Py_DECREF(fileno);
             if (fd == -1 && PyErr_Occurred()) {
                 goto error;