Add size checks to extension icons to prevent out of memory conditions

chrome/browser/ui/webui/favicon_source.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/webui/favicon_source.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "chrome/browser/favicon/favicon_service_factory.h"
 #include "chrome/browser/history/top_sites.h"
@@ skipping 64 matching lines @@
                    base::Unretained(this),
                    IconRequest(request_id, size_in_dip, scale_factor)),
         &cancelable_task_tracker_);
   } else {
     GURL url;
     if (path.size() > 5 && path.substr(0, 5) == "size/") {
       size_t slash = path.find("/", 5);
       size_t scale_delimiter = path.find("@", 5);
       std::string size = path.substr(5, slash - 5);
       size_in_dip = atoi(size.c_str());
-      DCHECK(size_in_dip == 64 || size_in_dip == 32 || size_in_dip == 16) <<
-          "only 64x64, 32x32 and 16x16 icons are supported";
+      if (size_in_dip != 64 && size_in_dip != 32 && size_in_dip != 16) {
+        // Only 64x64, 32x32 and 16x16 icons are supported
+        size_in_dip = 16;

[Mustafa Acer, 2012/12/14 19:29:25]

I'm hoping this won't break any case where a size 48 or any other nonstandard
favicon may be used somewhere in the ui.

[Matt Perry, 2012/12/14 19:33:44]

If we used sizes like that anywhere, we should have been hitting this DCHECK.
Since no one has noticed, I'm guessing we don't.

+      }
       // Optional scale factor.
       if (scale_delimiter != std::string::npos && scale_delimiter < slash) {
         DCHECK(size_in_dip == 16);
         std::string scale_str = path.substr(scale_delimiter + 1,
                                             slash - scale_delimiter - 1);
         web_ui_util::ParseScaleFactor(scale_str, &scale_factor);
       }
       url = GURL(path.substr(slash + 1));
     } else {
       // URL requests prefixed with "origin/" are converted to a form with an
@@ skipping 81 matching lines @@
 
   if (!default_favicon) {
     ui::ScaleFactor scale_factor = icon_request.scale_factor;
     default_favicon = ResourceBundle::GetSharedInstance()
         .LoadDataResourceBytesForScale(resource_id, scale_factor);
     default_favicons_[favicon_index] = default_favicon;
   }
 
   SendResponse(icon_request.request_id, default_favicon);
 }