Rename Result.Resp to Result.Body.
diff --git a/openstack/common/extensions/results.go b/openstack/common/extensions/results.go
index 123c33f..777d083 100755
--- a/openstack/common/extensions/results.go
+++ b/openstack/common/extensions/results.go
@@ -22,7 +22,7 @@
 		Extension *Extension `json:"extension"`
 	}
 
-	err := mapstructure.Decode(r.Resp, &res)
+	err := mapstructure.Decode(r.Body, &res)
 
 	return res.Extension, err
 }