Fixed #30044 -- Raised a FieldError on inherited field update attempts.

django/db/models/sql/query.py

@@ -1600,6 +1600,8 @@ class Query:
             field_list = name.split(LOOKUP_SEP)
             join_info = self.setup_joins(field_list, self.get_meta(), self.get_initial_alias(), can_reuse=reuse)
             targets, final_alias, join_list = self.trim_joins(join_info.targets, join_info.joins, join_info.path)
+            if not allow_joins and len(join_list) > 1:
+                raise FieldError('Joined field references are not permitted in this query')
             if len(targets) > 1:
                 raise FieldError("Referencing multicolumn fields with F() objects "
                                  "isn't supported")

tests/expressions/models.py

@@ -15,6 +15,10 @@ class Employee(models.Model):
         return '%s %s' % (self.firstname, self.lastname)
 
 
+class RemoteEmployee(Employee):
+    adjusted_salary = models.IntegerField()
+
+
 class Company(models.Model):
     name = models.CharField(max_length=100)
     num_employees = models.PositiveIntegerField()

tests/expressions/tests.py

@@ -24,8 +24,8 @@ from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
 from django.test.utils import Approximate
 
 from .models import (
-    UUID, UUIDPK, Company, Employee, Experiment, Number, Result, SimulationRun,
-    Time,
+    UUID, UUIDPK, Company, Employee, Experiment, Number, RemoteEmployee,
+    Result, SimulationRun, Time,
 )
 
 
@@ -285,6 +285,11 @@ class BasicExpressionsTests(TestCase):
         with self.assertRaisesMessage(FieldError, msg):
             test_gmbh.save()
 
+    def test_update_inherited_field_value(self):
+        msg = 'Joined field references are not permitted in this query'
+        with self.assertRaisesMessage(FieldError, msg):
+            RemoteEmployee.objects.update(adjusted_salary=F('salary') * 5)
+
     def test_object_update_unsaved_objects(self):
         # F expressions cannot be used to update attributes on objects which do
         # not yet exist in the database