gh-127776: Add GRND_INSECURE constant to os module

Doc/library/os.rst

@@ -5732,8 +5732,8 @@ Random numbers
    ``/dev/urandom`` devices.
 
    The flags argument is a bit mask that can contain zero or more of the
-   following values ORed together: :py:const:`os.GRND_RANDOM` and
-   :py:data:`GRND_NONBLOCK`.
+   following values ORed together: :py:const:`os.GRND_RANDOM`,
+   :py:data:`GRND_NONBLOCK` and :py:data:`GRND_INSECURE`.
 
    See also the `Linux getrandom() manual page
    <https://man7.org/linux/man-pages/man2/getrandom.2.html>`_.
@@ -5803,3 +5803,15 @@ Random numbers
    ``/dev/random`` pool instead of the ``/dev/urandom`` pool.
 
    .. versionadded:: 3.6
+
+.. data:: GRND_INSECURE
+
+   If this flag is set, then :func:`getrandom` will return pseudo-random data
+   even if the entropy pool has not yet been initialized.
+   (It cannot be used with :py:const:`os.GRND_RANDOM`.)
+
+   .. note::
+
+      It is not suitable for scenarios requiring secure cryptography.
+
+   .. versionadded:: next

Misc/NEWS.d/next/Library/2024-12-10-13-09-46.gh-issue-127776.7T-Yxn.rst

@@ -0,0 +1 @@
+Add the :data:`~os.GRND_INSECURE` constant to the :mod:`os` module.

Modules/posixmodule.c

@@ -17613,6 +17613,8 @@ all_ins(PyObject *m)
 #ifdef HAVE_GETRANDOM_SYSCALL
     if (PyModule_AddIntMacro(m, GRND_RANDOM)) return -1;
     if (PyModule_AddIntMacro(m, GRND_NONBLOCK)) return -1;
+    /* Linux 5.6+ */
+    if (PyModule_AddIntMacro(m, GRND_INSECURE)) return -1;
 #endif
 #ifdef HAVE_MEMFD_CREATE
     if (PyModule_AddIntMacro(m, MFD_CLOEXEC)) return -1;