Prevent smallint overflow in webhook.recent_failures

Changelog: fixed

app/services/web_hook_service.rb

@@ -27,6 +27,7 @@ class WebHookService
 
   REQUEST_BODY_SIZE_LIMIT = 25.megabytes
   GITLAB_EVENT_HEADER = 'X-Gitlab-Event'
+  MAX_FAILURES = 100
 
   attr_accessor :hook, :data, :hook_name, :request_options
 
@@ -141,7 +142,7 @@ class WebHookService
       next_backoff = hook.next_backoff
       hook.update!(disabled_until: next_backoff.from_now, backoff_count: hook.backoff_count + 1)
     else
-      hook.update!(recent_failures: hook.recent_failures + 1)
+      hook.update!(recent_failures: hook.recent_failures + 1) if hook.recent_failures < MAX_FAILURES
     end
   end
 

spec/services/web_hook_service_spec.rb

@@ -240,6 +240,25 @@ RSpec.describe WebHookService do
         it 'does not change the disabled_until attribute' do
           expect { service_instance.execute }.not_to change(project_hook, :disabled_until)
         end
+
+        it 'does not allow the failure count to overflow' do
+          project_hook.update!(recent_failures: 32767)
+
+          expect { service_instance.execute }.not_to change(project_hook, :recent_failures)
+        end
+
+        context 'when the web_hooks_disable_failed FF is disabled' do
+          before do
+            # Hook will only be executed if the flag is disabled.
+            stub_feature_flags(web_hooks_disable_failed: false)
+          end
+
+          it 'does not allow the failure count to overflow' do
+            project_hook.update!(recent_failures: 32767)
+
+            expect { service_instance.execute }.not_to change(project_hook, :recent_failures)
+          end
+        end
       end
 
       context 'with exception' do