From d9ca68fb6bee7c7262b01866b35fdb08060cfb4b Mon Sep 17 00:00:00 2001
From: Bob Owen <bobowencode@gmail.com>
Date: Thu, 10 Aug 2023 08:31:24 +0000
Subject: [PATCH] Bug 1846687: Don't allow CanvasTranslator to be initialized
 twice. r=jrmuizel

Differential Revision: https://phabricator.services.mozilla.com/D185548
---
 gfx/layers/ipc/CanvasTranslator.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gfx/layers/ipc/CanvasTranslator.cpp b/gfx/layers/ipc/CanvasTranslator.cpp
index a6325cccba3f..e88fb5a5003a 100644
--- a/gfx/layers/ipc/CanvasTranslator.cpp
+++ b/gfx/layers/ipc/CanvasTranslator.cpp
@@ -131,6 +131,10 @@ mozilla::ipc::IPCResult CanvasTranslator::RecvInitTranslator(
     ipc::SharedMemoryBasic::Handle&& aReadHandle,
     CrossProcessSemaphoreHandle&& aReaderSem,
     CrossProcessSemaphoreHandle&& aWriterSem) {
+  if (mStream) {
+    return IPC_FAIL(this, "RecvInitTranslator called twice.");
+  }
+
   mTextureType = aTextureType;
 
   // We need to initialize the stream first, because it might be used to