tor-browser

commit 19e9ef1bce3ed49c583c7ec0ea647d7aef794aaa
parent 04a9348e2e941256fb9da68a766b08b5a00c52f8
Author: Harveer Singh <hsingh@mozilla.com>
Date:   Fri, 14 Nov 2025 15:53:26 +0000

Bug 1995558: Service worker module registration should be rejected in case of any evaluation errors.r=edenchuang,dom-worker-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D269457

Diffstat:
M
dom/workers/loader/WorkerModuleLoader.cpp
 | 
5
+++++
M
dom/workers/loader/WorkerModuleLoader.h
 | 
2
++
M
js/loader/ModuleLoaderBase.cpp
 | 
16
+++++++++++++++-
M
js/loader/ModuleLoaderBase.h
 | 
2
++

4 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/dom/workers/loader/WorkerModuleLoader.cpp b/dom/workers/loader/WorkerModuleLoader.cpp
@@ -128,6 +128,11 @@ bool WorkerModuleLoader::IsDynamicImportSupported() {
   return !workerPrivate->IsServiceWorker();
 }
 
+bool WorkerModuleLoader::IsForServiceWorker() const {
+  WorkerPrivate* workerPrivate = GetCurrentThreadWorkerPrivate();
+  return workerPrivate && workerPrivate->IsServiceWorker();
+}
+
 bool WorkerModuleLoader::CanStartLoad(ModuleLoadRequest* aRequest,
                                       nsresult* aRvOut) {
   return true;
diff --git a/dom/workers/loader/WorkerModuleLoader.h b/dom/workers/loader/WorkerModuleLoader.h
@@ -98,6 +98,8 @@ class WorkerModuleLoader : public JS::loader::ModuleLoaderBase {
     return aModuleType == JS::ModuleType::JavaScript ||
            aModuleType == JS::ModuleType::JSON;
   }
+
+  virtual bool IsForServiceWorker() const override;
 };
 
 }  // namespace mozilla::dom::workerinternals::loader
diff --git a/js/loader/ModuleLoaderBase.cpp b/js/loader/ModuleLoaderBase.cpp
@@ -1478,7 +1478,14 @@ nsresult ModuleLoaderBase::EvaluateModule(ModuleLoadRequest* aRequest) {
   mozilla::dom::AutoEntryScript aes(mGlobalObject, "EvaluateModule",
                                     NS_IsMainThread());
 
-  return EvaluateModuleInContext(aes.cx(), aRequest, ReportModuleErrorsAsync);
+  // We would like to handle any evaluation errors synchronously for service
+  // workers immediately such that if we are performing service worker
+  // registration we can fail it right away rather than having it fail later on
+  // an event loop turn which might be too late and the registration process
+  // would have succeeded by then.
+  return EvaluateModuleInContext(
+      aes.cx(), aRequest,
+      IsForServiceWorker() ? ThrowModuleErrorsSync : ReportModuleErrorsAsync);
 }
 
 nsresult ModuleLoaderBase::EvaluateModuleInContext(
@@ -1554,6 +1561,13 @@ nsresult ModuleLoaderBase::EvaluateModuleInContext(
   // If the promise is rejected, the value is unwrapped from the promise value.
   if (!ThrowOnModuleEvaluationFailure(aCx, evaluationPromise, errorBehaviour)) {
     LOG(("ScriptLoadRequest (%p):   evaluation failed on throw", aRequest));
+
+    if (IsForServiceWorker()) {
+      // If this module eval is being done for service workers, then we would
+      // like to throw/return right from here, such that if we are in
+      // registration phase, we can fail it synchronously right away.
+      return NS_ERROR_ABORT;
+    }
   }
 
   // TODO: Bug 1973321: Prepare Bytecode encoding for dynamic import
diff --git a/js/loader/ModuleLoaderBase.h b/js/loader/ModuleLoaderBase.h
@@ -333,6 +333,8 @@ class ModuleLoaderBase : public nsISupports {
 
   virtual bool IsDynamicImportSupported() { return true; }
 
+  virtual bool IsForServiceWorker() const { return false; }
+
   // Called when dynamic import started successfully.
   virtual void OnDynamicImportStarted(ModuleLoadRequest* aRequest) {}