Bug 1780741 - Add init checks to ExternalHelperAppParent. r=nika

Differential Revision: https://phabricator.services.mozilla.com/D152633

dom/ipc/ContentParent.cpp

@@ -4426,9 +4426,11 @@ mozilla::ipc::IPCResult ContentParent::RecvPExternalHelperAppConstructor(
     nsIURI* aReferrer, const MaybeDiscarded<BrowsingContext>& aContext,
     const bool& aShouldCloseWindow) {
   BrowsingContext* context = aContext.IsDiscarded() ? nullptr : aContext.get();
-  static_cast<ExternalHelperAppParent*>(actor)->Init(
-      loadInfoArgs, aMimeContentType, aForceSave, aReferrer, context,
-      aShouldCloseWindow);
+  if (!static_cast<ExternalHelperAppParent*>(actor)->Init(
+          loadInfoArgs, aMimeContentType, aForceSave, aReferrer, context,
+          aShouldCloseWindow)) {
+    return IPC_FAIL(this, "Init failed.");
+  }
   return IPC_OK();
 }
 

uriloader/exthandler/ExternalHelperAppParent.cpp

@@ -58,13 +58,16 @@ ExternalHelperAppParent::ExternalHelperAppParent(
   }
 }
 
-void ExternalHelperAppParent::Init(
+bool ExternalHelperAppParent::Init(
     const Maybe<mozilla::net::LoadInfoArgs>& aLoadInfoArgs,
     const nsACString& aMimeContentType, const bool& aForceSave,
     nsIURI* aReferrer, BrowsingContext* aContext,
     const bool& aShouldCloseWindow) {
-  mozilla::ipc::LoadInfoArgsToLoadInfo(aLoadInfoArgs,
+  nsresult rv = mozilla::ipc::LoadInfoArgsToLoadInfo(aLoadInfoArgs,
                                        getter_AddRefs(mLoadInfo));
+  if (NS_FAILED(rv)) {
+    return false;
+  }
 
   nsCOMPtr<nsIExternalHelperAppService> helperAppService =
       do_GetService(NS_EXTERNALHELPERAPPSERVICE_CONTRACTID);
@@ -90,12 +93,18 @@ void ExternalHelperAppParent::Init(
 
   helperAppService->CreateListener(aMimeContentType, this, aContext, aForceSave,
                                    nullptr, getter_AddRefs(mListener));
+  if (!mListener) {
+    return false;
+  }
+
   if (aShouldCloseWindow) {
     RefPtr<nsExternalAppHandler> handler = do_QueryObject(mListener);
     if (handler) {
       handler->SetShouldCloseWindow();
     }
   }
+
+  return true;
 }
 
 void ExternalHelperAppParent::ActorDestroy(ActorDestroyReason why) {

uriloader/exthandler/ExternalHelperAppParent.h

@@ -85,7 +85,7 @@ class ExternalHelperAppParent
                           const nsACString& aContentDispositionHeader,
                           const uint32_t& aContentDispositionHint,
                           const nsAString& aContentDispositionFilename);
-  void Init(const Maybe<mozilla::net::LoadInfoArgs>& aLoadInfoArgs,
+  bool Init(const Maybe<mozilla::net::LoadInfoArgs>& aLoadInfoArgs,
             const nsACString& aMimeContentType, const bool& aForceSave,
             nsIURI* aReferrer, BrowsingContext* aContext,
             const bool& aShouldCloseWindow);