[cryptohome] make guest-mode homedir mount with -rwx------

mount.cc

-// Copyright (c) 2009-2010 The Chromium OS Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Contains the implementation of class Mount
 
 #include "mount.h"
 
 #include <errno.h>
 
 #include <base/file_util.h>
@@ skipping 830 matching lines @@
   if (set_vault_ownership_) {
     if (!platform_->SetOwnership(home_dir_, default_user_, default_group_)) {
       LOG(ERROR) << "Couldn't change owner (" << default_user_ << ":"
                  << default_group_ << ") of guestfs path: "
                  << home_dir_.c_str();
       bool was_busy;
       platform_->Unmount(home_dir_.c_str(), false, &was_busy);
       return false;
     }
   }
+  if (!platform_->SetPermissions(home_dir_, S_IRUSR | S_IWUSR | S_IXUSR))

[Will Drewry, 2011/04/21 21:42:09]

Doesn't this need to call platform_->Unmount if it fails?

(nit: it'd be nice to have it as a constant like kDefaultMask, but since it is
only used here, I think it's fine as is.)

+    return false;
   CopySkeleton();
   return true;
 }
 
 string Mount::GetUserDirectory(const Credentials& credentials) const {
   return StringPrintf("%s/%s",
                       shadow_root_.c_str(),
                       credentials.GetObfuscatedUsername(system_salt_).c_str());
 }
 
@@ skipping 255 matching lines @@
     if (error) {
       *error = Mount::MOUNT_ERROR_KEY_FAILURE;
     }
     return false;
   }
 
   return true;
 }
 
 } // namespace cryptohome