From e01dca10480ca47b03ed6d02dade15d83e933102 Mon Sep 17 00:00:00 2001
From: Ehsan Akhgari <ehsan@mozilla.com>
Date: Mon, 13 Aug 2018 15:54:55 -0400
Subject: [PATCH] Bug 1482988 - Handle null arguments in
 nsContentUtils::StorageDisabledByAntiTracking correctly; r=smaug

---
 dom/base/nsContentUtils.cpp | 26 +++++++++++++++++---------
 dom/base/nsContentUtils.h   |  1 +
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index 7ed02a9293a7..e066961b25ca 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -8902,16 +8902,24 @@ nsContentUtils::StorageDisabledByAntiTracking(nsPIDOMWindowInner* aWindow,
       return false;
     }
 
-    // FIXME: this is wrong. This method is called also with aWindow and a null
-    // aChannel.
-    nsCOMPtr<mozIDOMWindowProxy> win;
-    nsresult rv = thirdPartyUtil->GetTopWindowForChannel(aChannel,
-                                                         getter_AddRefs(win));
-    NS_ENSURE_SUCCESS(rv, false);
-    auto* pwin = nsPIDOMWindowOuter::From(win);
+    nsCOMPtr<nsPIDOMWindowOuter> pwin;
+    if (aWindow) {
+      auto* outer = nsGlobalWindowOuter::Cast(aWindow->GetOuterWindow());
+      if (outer) {
+        pwin = outer->GetTopOuter();
+      }
+    } else if (aChannel) {
+      nsCOMPtr<mozIDOMWindowProxy> win;
+      nsresult rv = thirdPartyUtil->GetTopWindowForChannel(aChannel,
+                                                           getter_AddRefs(win));
+      NS_ENSURE_SUCCESS(rv, false);
+      pwin = nsPIDOMWindowOuter::From(win);
+    }
 
-    pwin->NotifyContentBlockingState(
-      nsIWebProgressListener::STATE_BLOCKED_TRACKING_COOKIES, aChannel);
+    if (pwin) {
+      pwin->NotifyContentBlockingState(
+        nsIWebProgressListener::STATE_BLOCKED_TRACKING_COOKIES, aChannel);
+    }
   }
   return disabled;
 }
diff --git a/dom/base/nsContentUtils.h b/dom/base/nsContentUtils.h
index 0ec54a945520..9334159c7626 100644
--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -2953,6 +2953,7 @@ public:
   /*
    * Returns true if this window/channel/aPrincipal should disable storages
    * because of the anti-tracking feature.
+   * Note that either aWindow or aChannel may be null when calling this function.
    */
   static bool StorageDisabledByAntiTracking(nsPIDOMWindowInner* aWindow,
                                             nsIChannel* aChannel,