Add an exception to DownloadManager::GenerateExtension() for .tar.gz files wi...

chrome/browser/download/download_manager.cc

 // Copyright (c) 2006-2008 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/download/download_manager.h"
 
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/path_service.h"
@@ skipping 1124 matching lines @@
   if (extension.empty()) {
     net::GetPreferredExtensionForMimeType(mime_type, &extension);
   } else {
     // Append extension generated from the mime type if:
     // 1. New extension is not ".txt"
     // 2. New extension is not the same as the already existing extension.
     // 3. New extension is not executable. This action mitigates the case when
     //    an executable is hidden in a benign file extension;
     //    E.g. my-cat.jpg becomes my-cat.jpg.js if content type is
     //         application/x-javascript.
+    // 4. New extension is not ".tar" for .gz files. For misconfigured web
+    //    servers, i.e. bug 5772.
     FilePath::StringType append_extension;
     if (net::GetPreferredExtensionForMimeType(mime_type, &append_extension)) {
       if (append_extension != FILE_PATH_LITERAL("txt") &&
           append_extension != extension &&
-          !IsExecutable(append_extension)) {
+          !IsExecutable(append_extension) &&
+          (append_extension != FILE_PATH_LITERAL("tar") ||
+           extension != FILE_PATH_LITERAL("gz"))) {
         extension += FILE_PATH_LITERAL(".");
         extension += append_extension;
       }
     }
   }
 
   generated_extension->swap(extension);
 }
 
 void DownloadManager::GenerateFilename(DownloadCreateInfo* info,
@@ skipping 280 matching lines @@
       searched_downloads.push_back(dit->second);
   }
 
   requestor->SetDownloads(searched_downloads);
 }
 
 // Clears the last download path, used to initialize "save as" dialogs.
 void DownloadManager::ClearLastDownloadPath() {
   last_download_path_ = FilePath();
 }