diff -r 95be8b7181d3 -r 75e4bae56068 mercurial/ui.py
--- a/mercurial/ui.py	Wed Mar 15 20:43:12 2017 -0700
+++ b/mercurial/ui.py	Sun Mar 12 11:43:31 2017 -0700
@@ -542,7 +542,7 @@
         ConfigError: foo.invalid is not a byte quantity ('somevalue')
         """
 
-        value = self.config(section, name)
+        value = self.config(section, name, None, untrusted)
         if value is None:
             if not isinstance(default, str):
                 return default