Only re-sign our own events

synapse/federation/federation_server.py

@@ -193,6 +193,9 @@ class FederationServer(FederationBase):
             )
 
             for event in auth_chain:
+                # We sign these again because there was a bug where we
+                # incorrectly signed things the first time round
+                if self.hs.is_mine_id(event.event_id):
                     event.signatures.update(
                         compute_event_signature(
                             event,

synapse/handlers/federation.py

@@ -1018,6 +1018,9 @@ class FederationHandler(BaseHandler):
 
             res = results.values()
             for event in res:
+                # We sign these again because there was a bug where we
+                # incorrectly signed things the first time round
+                if self.hs.is_mine_id(event.event_id):
                     event.signatures.update(
                         compute_event_signature(
                             event,