[5.1.x] Fixed #35483 -- Added NUL (0x00) character validation to ModelChoiceFields.

Applied the ProhibitNullCharactersValidator to ModelChoiceField and ModelMultipleChoiceField.

Co-authored-by: Viktor Paripás <viktor.paripas@gmail.com>
Co-authored-by: Vasyl Dizhak <vasyl@dizhak.com>
Co-authored-by: Arthur Vasconcelos <vasconcelos.arthur@gmail.com>

Backport of 38ad710aba885ad26944ff5708ce1a02a446d2d3 from main.

2 files changed, 16 insertions, 1 deletions

diff --git a/tests/model_forms/test_modelchoicefield.py b/tests/model_forms/test_modelchoicefield.py
index 19e9db69a0..83d801768a 100644
--- a/tests/model_forms/test_modelchoicefield.py
+++ b/tests/model_forms/test_modelchoicefield.py
@@ -7,7 +7,7 @@ from django.forms.widgets import CheckboxSelectMultiple
 from django.template import Context, Template
 from django.test import TestCase
 
-from .models import Article, Author, Book, Category, Writer
+from .models import Article, Author, Book, Category, ExplicitPK, Writer
 
 
 class ModelChoiceFieldTests(TestCase):
@@ -79,6 +79,12 @@ class ModelChoiceFieldTests(TestCase):
         self.assertEqual(f.clean(self.c1.slug), self.c1)
         self.assertEqual(f.clean(self.c1), self.c1)
 
+    def test_model_choice_null_characters(self):
+        f = forms.ModelChoiceField(queryset=ExplicitPK.objects.all())
+        msg = "Null characters are not allowed."
+        with self.assertRaisesMessage(ValidationError, msg):
+            f.clean("\x00something")
+
     def test_choices(self):
         f = forms.ModelChoiceField(
             Category.objects.filter(pk=self.c1.id), required=False
diff --git a/tests/model_forms/tests.py b/tests/model_forms/tests.py
index 3f927cb053..c6e12e1aab 100644
--- a/tests/model_forms/tests.py
+++ b/tests/model_forms/tests.py
@@ -2227,6 +2227,15 @@ class ModelMultipleChoiceFieldTests(TestCase):
         f = forms.ModelMultipleChoiceField(queryset=Writer.objects.all())
         self.assertNumQueries(1, f.clean, [p.pk for p in persons[1:11:2]])
 
+    def test_model_multiple_choice_null_characters(self):
+        f = forms.ModelMultipleChoiceField(queryset=ExplicitPK.objects.all())
+        msg = "Null characters are not allowed."
+        with self.assertRaisesMessage(ValidationError, msg):
+            f.clean(["\x00something"])
+
+        with self.assertRaisesMessage(ValidationError, msg):
+            f.clean(["valid", "\x00something"])
+
     def test_model_multiple_choice_run_validators(self):
         """
         ModelMultipleChoiceField run given validators (#14144).