Bug 1667294 - Skip parts of SandboxBroker::LaunchApp when launching a Thunderbird process. r=tkikuchi

Thunderbird does not yet have the same blocklist initialization as Firefox, so we skip calling InitDllBlocklistOOP to avoid a MOZ_RELEASE_ASSERT.

Differential Revision: https://phabricator.services.mozilla.com/D99173

mozglue/dllservices/ModuleLoadFrame.cpp

@@ -38,6 +38,13 @@ void ModuleLoadFrame::StaticInit(
     // the launcher process blocklist.
     gFallbackLoaderAPI.SetObserver(aNewObserver);
     sLoaderAPI = &gFallbackLoaderAPI;
+
+    if (aOutWinLauncherFunctions) {
+      aOutWinLauncherFunctions->mHandleLauncherError =
+          [](const mozilla::LauncherError&, const char*) {};
+      // We intentionally leave mInitDllBlocklistOOP null to make sure calling
+      // mInitDllBlocklistOOP in non-Firefox hits MOZ_RELEASE_ASSERT.
+    }
     return;
   }
 

security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp

@@ -313,7 +313,16 @@ bool SandboxBroker::LaunchApp(const wchar_t* aPath, const wchar_t* aArguments,
           last_error, last_warning);
   }
 
-  if (XRE_GetChildProcBinPathType(aProcessType) == BinPathType::Self) {
+#ifdef MOZ_THUNDERBIRD
+  // In Thunderbird, mInitDllBlocklistOOP is null, so InitDllBlocklistOOP would
+  // hit MOZ_RELEASE_ASSERT.
+  constexpr bool isThunderbird = true;
+#else
+  constexpr bool isThunderbird = false;
+#endif
+
+  if (!isThunderbird &&
+      XRE_GetChildProcBinPathType(aProcessType) == BinPathType::Self) {
     RefPtr<DllServices> dllSvc(DllServices::Get());
     LauncherVoidResultWithLineInfo blocklistInitOk =
         dllSvc->InitDllBlocklistOOP(aPath, targetInfo.hProcess,