diff --git a/qubes/storage/__init__.py b/qubes/storage/__init__.py
index dcdc32ff..0af1ad27 100644
--- a/qubes/storage/__init__.py
+++ b/qubes/storage/__init__.py
@@ -310,7 +310,7 @@ class Storage(object):
 
     def create(self):
         ''' Creates volumes on disk '''
-        old_umask = os.umask(002)
+        old_umask = os.umask(0o002)
 
         for volume in self.vm.volumes.values():
             self.get_pool(volume).create(volume)
diff --git a/qubes/storage/file.py b/qubes/storage/file.py
index 3f899f90..62b813c9 100644
--- a/qubes/storage/file.py
+++ b/qubes/storage/file.py
@@ -186,7 +186,7 @@ class FilePool(qubes.storage.Pool):
             old_path = volume.path_cow + '.old'
             os.rename(volume.path_cow, old_path)
 
-        old_umask = os.umask(002)
+        old_umask = os.umask(0o002)
         with open(volume.path_cow, 'w') as f_cow:
             f_cow.truncate(volume.size)
         os.umask(old_umask)
diff --git a/qubes/vm/__init__.py b/qubes/vm/__init__.py
index 7ccf4c9f..673eef2f 100644
--- a/qubes/vm/__init__.py
+++ b/qubes/vm/__init__.py
@@ -325,7 +325,7 @@ class BaseVM(qubes.PropertyHolder):
         tree = lxml.etree.ElementTree(root)
 
         try:
-            old_umask = os.umask(002)
+            old_umask = os.umask(0o002)
             with open(os.path.join(self.dir_path,
                     self.firewall_conf), 'w') as fd:
                 tree.write(fd, encoding="UTF-8", pretty_print=True)