From 9ef24d3f43022f61044756741f40e095e9290bc1 Mon Sep 17 00:00:00 2001
From: jeremystretch <jstretch@ns1.com>
Date: Mon, 3 Oct 2022 10:39:03 -0400
Subject: [PATCH] Fixes #10513: Disable the reassignment of a module to a new
 device

---
 docs/release-notes/version-3.3.md | 1 +
 netbox/dcim/forms/models.py       | 1 +
 netbox/dcim/models/devices.py     | 8 ++++++++
 netbox/dcim/tests/test_views.py   | 5 +++--
 4 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/docs/release-notes/version-3.3.md b/docs/release-notes/version-3.3.md
index e91e825f5..2c2db9e47 100644
--- a/docs/release-notes/version-3.3.md
+++ b/docs/release-notes/version-3.3.md
@@ -16,6 +16,7 @@
 * [#10461](https://github.com/netbox-community/netbox/issues/10461) - Enable filtering by read-only custom fields in the UI
 * [#10470](https://github.com/netbox-community/netbox/issues/10470) - Omit read-only custom fields from CSV import forms
 * [#10480](https://github.com/netbox-community/netbox/issues/10480) - Cable trace SVG links should not force a new window
+* [#10513](https://github.com/netbox-community/netbox/issues/10513) - Disable the reassignment of a module to a new device
 
 ---
 
diff --git a/netbox/dcim/forms/models.py b/netbox/dcim/forms/models.py
index b33023ece..1f1c869a5 100644
--- a/netbox/dcim/forms/models.py
+++ b/netbox/dcim/forms/models.py
@@ -679,6 +679,7 @@ class ModuleForm(NetBoxModelForm):
         super().__init__(*args, **kwargs)
 
         if self.instance.pk:
+            self.fields['device'].disabled = True
             self.fields['replicate_components'].initial = False
             self.fields['replicate_components'].disabled = True
             self.fields['adopt_components'].initial = False
diff --git a/netbox/dcim/models/devices.py b/netbox/dcim/models/devices.py
index ccf4613bf..4c542341e 100644
--- a/netbox/dcim/models/devices.py
+++ b/netbox/dcim/models/devices.py
@@ -987,6 +987,14 @@ class Module(NetBoxModel, ConfigContextModel):
     def get_absolute_url(self):
         return reverse('dcim:module', args=[self.pk])
 
+    def clean(self):
+        super().clean()
+
+        if self.module_bay.device != self.device:
+            raise ValidationError(
+                f"Module must be installed within a module bay belonging to the assigned device ({self.device})."
+            )
+
     def save(self, *args, **kwargs):
         is_new = self.pk is None
 
diff --git a/netbox/dcim/tests/test_views.py b/netbox/dcim/tests/test_views.py
index 50b36e36d..db3495521 100644
--- a/netbox/dcim/tests/test_views.py
+++ b/netbox/dcim/tests/test_views.py
@@ -1778,10 +1778,12 @@ class ModuleTestCase(
             ModuleBay(device=devices[0], name='Module Bay 2'),
             ModuleBay(device=devices[0], name='Module Bay 3'),
             ModuleBay(device=devices[0], name='Module Bay 4'),
+            ModuleBay(device=devices[0], name='Module Bay 5'),
             ModuleBay(device=devices[1], name='Module Bay 1'),
             ModuleBay(device=devices[1], name='Module Bay 2'),
             ModuleBay(device=devices[1], name='Module Bay 3'),
             ModuleBay(device=devices[1], name='Module Bay 4'),
+            ModuleBay(device=devices[1], name='Module Bay 5'),
         )
         ModuleBay.objects.bulk_create(module_bays)
 
@@ -1795,7 +1797,7 @@ class ModuleTestCase(
         tags = create_tags('Alpha', 'Bravo', 'Charlie')
 
         cls.form_data = {
-            'device': devices[1].pk,
+            'device': devices[0].pk,
             'module_bay': module_bays[3].pk,
             'module_type': module_types[0].pk,
             'serial': 'A',
@@ -1867,7 +1869,6 @@ class ModuleTestCase(
         self.assertIsNone(interface.module)
 
         # Create a module with adopted components
-        form_data['module_bay'] = ModuleBay.objects.filter(device=device).first()
         form_data['module_type'] = module_type
         form_data['replicate_components'] = False
         form_data['adopt_components'] = True