Fixed #22956 -- Made PermissionManager.get_by_natural_key() use the correct database for content type lookup.

django/contrib/auth/models.py

@@ -32,8 +32,7 @@ class PermissionManager(models.Manager):
     def get_by_natural_key(self, codename, app_label, model):
         return self.get(
             codename=codename,
-            content_type=ContentType.objects.get_by_natural_key(app_label,
-                                                                model),
+            content_type=ContentType.objects.db_manager(self.db).get_by_natural_key(app_label, model),
         )
 
 

django/contrib/auth/tests/test_models.py

@@ -1,6 +1,7 @@
 from django.contrib.auth import get_user_model
-from django.contrib.auth.models import AbstractUser, Group, User, UserManager
+from django.contrib.auth.models import AbstractUser, Group, Permission, User, UserManager
 from django.contrib.auth.tests.utils import skipIfCustomUser
+from django.contrib.contenttypes.models import ContentType
 from django.core import mail
 from django.db.models.signals import post_save
 from django.test import TestCase, override_settings
@@ -43,6 +44,64 @@ class LoadDataWithNaturalKeysTestCase(TestCase):
         self.assertEqual(group, user.groups.get())
 
 
+class LoadDataWithNaturalKeysAndMultipleDatabasesTestCase(TestCase):
+    multi_db = True
+
+    def test_load_data_with_user_permissions(self):
+        # Create test contenttypes for both databases
+        default_objects = [
+            ContentType.objects.db_manager('default').create(
+                model='examplemodela',
+                name='example model a',
+                app_label='app_a',
+            ),
+            ContentType.objects.db_manager('default').create(
+                model='examplemodelb',
+                name='example model b',
+                app_label='app_b',
+            ),
+        ]
+        other_objects = [
+            ContentType.objects.db_manager('other').create(
+                model='examplemodelb',
+                name='example model b',
+                app_label='app_b',
+            ),
+            ContentType.objects.db_manager('other').create(
+                model='examplemodela',
+                name='example model a',
+                app_label='app_a',
+            ),
+        ]
+
+        # Now we create the test UserPermission
+        Permission.objects.db_manager("default").create(
+            name="Can delete example model b",
+            codename="delete_examplemodelb",
+            content_type=default_objects[1],
+        )
+        Permission.objects.db_manager("other").create(
+            name="Can delete example model b",
+            codename="delete_examplemodelb",
+            content_type=other_objects[0],
+        )
+
+        perm_default = Permission.objects.get_by_natural_key(
+            'delete_examplemodelb',
+            'app_b',
+            'examplemodelb',
+        )
+
+        perm_other = Permission.objects.db_manager('other').get_by_natural_key(
+            'delete_examplemodelb',
+            'app_b',
+            'examplemodelb',
+        )
+
+        self.assertEqual(perm_default.content_type_id, default_objects[1].id)
+        self.assertEqual(perm_other.content_type_id, other_objects[0].id)
+
+
 @skipIfCustomUser
 class UserManagerTestCase(TestCase):