From 30e8509fd25aaacd3479f67b8d1b2442aafd3c7f Mon Sep 17 00:00:00 2001
From: roytam1 <roytam@gmail.com>
Date: Mon, 11 Apr 2022 23:50:02 +0800
Subject: [PATCH] ported from esr91: Bug 1761026 - Add a null check for
 FetchDriver::mResponse, r=necko-reviewers,dragana a=dmeehan (3b54d6b5)

---
 dom/fetch/FetchDriver.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dom/fetch/FetchDriver.cpp b/dom/fetch/FetchDriver.cpp
index 79bd5a0e39..35d929c89d 100644
--- a/dom/fetch/FetchDriver.cpp
+++ b/dom/fetch/FetchDriver.cpp
@@ -721,10 +721,14 @@ FetchDriver::OnDataAvailable(nsIRequest* aRequest,
     }
   }
 
+  if (!mResponse) {
+    MOZ_ASSERT(false);
+    return NS_ERROR_UNEXPECTED;
+  }
+
   // Explicitly initialized to 0 because in some cases nsStringInputStream may
   // not write to aRead.
   uint32_t aRead = 0;
-  MOZ_ASSERT(mResponse);
   MOZ_ASSERT(mPipeOutputStream);
 
   // From "Main Fetch" step 17: SRI-part2.