diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py
index 762e4b8014e7b017f6213e9476b59e36879248c5..30e2742102d6330dd6d3beb99f01df67d0fb2e75 100644
--- a/synapse/crypto/keyring.py
+++ b/synapse/crypto/keyring.py
@@ -512,7 +512,7 @@ class Keyring(object):
                 continue
 
             (response, tls_certificate) = yield fetch_server_key(
-                server_name, self.tls_client_options_factory,
+                server_name, self.hs.tls_client_options_factory,
                 path=(b"/_matrix/key/v2/server/%s" % (
                     urllib.quote(requested_key_id),
                 )).encode("ascii"),