[tbb-commits] [tor-browser/tor-browser-31.6.0esr-4.5-1] fixup! Bug #5856: Do not expose physical screen info via window & window.screen.

[mikeperry at torproject.org]

commit a5648c8d80f396caf294d761cc4a9a76c0b33a9d
Author: Arthur Edelstein <arthuredelstein at gmail.com>
Date:   Wed Apr 8 22:55:41 2015 -0700

    fixup! Bug #5856: Do not expose physical screen info via window & window.screen.
---
 dom/base/nsGlobalWindow.cpp |   11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/dom/base/nsGlobalWindow.cpp b/dom/base/nsGlobalWindow.cpp
index 9fc9c31..2f85d60 100644
--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -4867,9 +4867,9 @@ nsGlobalWindow::GetOuterSize(ErrorResult& aError)
   MOZ_ASSERT(IsOuterWindow());
 
   if (!IsChrome()) {
-    CSSIntSize size;                                                                                                                                                                                       
-    aError = GetInnerSize(size);                                                                                                                                                                           
-    return nsIntSize(size.width, size.height);  
+    CSSIntSize size;
+    aError = GetInnerSize(size);
+    return nsIntSize(size.width, size.height);
   }
 
   nsCOMPtr<nsIBaseWindow> treeOwnerAsWin = GetTreeOwnerWindow();
@@ -5114,6 +5114,11 @@ nsGlobalWindow::GetDevicePixelRatio(ErrorResult& aError)
 {
   FORWARD_TO_OUTER_OR_THROW(GetDevicePixelRatio, (aError), aError, 0.0);
 
+  // For non-chrome callers, always return 1.0 to prevent fingerprinting.
+  if (!IsChrome()) {
+    return 1.0;
+  }
+
   if (!mDocShell) {
     return 1.0;
   }