[5.1.x] Fixed #35942 -- Fixed createsuperuser crash on Python 3.13+ when username is unavailable.

Thanks Mariusz Felisiak and Jacob Tyler Walls for reviews.

Backport of c635decb00ac957daf81c08541cdc9cf46f6d86d from main.

3 files changed, 15 insertions, 5 deletions

diff --git a/django/contrib/auth/management/__init__.py b/django/contrib/auth/management/__init__.py
index c40f2aa69d..a8639cb258 100644
--- a/django/contrib/auth/management/__init__.py
+++ b/django/contrib/auth/management/__init__.py
@@ -115,10 +115,12 @@ def get_system_username():
     """
     try:
         result = getpass.getuser()
-    except (ImportError, KeyError):
-        # KeyError will be raised by os.getpwuid() (called by getuser())
-        # if there is no corresponding entry in the /etc/passwd file
-        # (a very restricted chroot environment, for example).
+    except (ImportError, KeyError, OSError):
+        # TODO: Drop ImportError and KeyError when dropping support for PY312.
+        # KeyError (Python <3.13) or OSError (Python 3.13+) will be raised by
+        # os.getpwuid() (called by getuser()) if there is no corresponding
+        # entry in the /etc/passwd file (for example, in a very restricted
+        # chroot environment).
         return ""
     return result
 
diff --git a/docs/releases/5.1.4.txt b/docs/releases/5.1.4.txt
index bee40f243e..468bd46381 100644
--- a/docs/releases/5.1.4.txt
+++ b/docs/releases/5.1.4.txt
@@ -9,4 +9,5 @@ Django 5.1.4 fixes several bugs in 5.1.3.
 Bugfixes
 ========
 
-* ...
+* Fixed a crash in ``createsuperuser`` on Python 3.13+ caused by an unhandled
+  ``OSError`` when the username could not be determined (:ticket:`35942`).
diff --git a/tests/auth_tests/test_management.py b/tests/auth_tests/test_management.py
index 5765c50034..0ef85a7299 100644
--- a/tests/auth_tests/test_management.py
+++ b/tests/auth_tests/test_management.py
@@ -126,6 +126,13 @@ class GetDefaultUsernameTestCase(TestCase):
     def test_actual_implementation(self):
         self.assertIsInstance(management.get_system_username(), str)
 
+    def test_getuser_raises_exception(self):
+        # TODO: Drop ImportError and KeyError when dropping support for PY312.
+        for exc in (ImportError, KeyError, OSError):
+            with self.subTest(exc=str(exc)):
+                with mock.patch("getpass.getuser", side_effect=exc):
+                    self.assertEqual(management.get_system_username(), "")
+
     def test_simple(self):
         management.get_system_username = lambda: "joe"
         self.assertEqual(management.get_default_username(), "joe")