From 0a7fb2471685cf4bccfd76f51ddd614a3aeb4536 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Thu, 30 Jul 2020 16:58:57 +0100 Subject: Fix invite rejection when we have no forward-extremeties (#7980) Thanks to some slightly overzealous cleanup in the `delete_old_current_state_events`, it's possible to end up with no `event_forward_extremities` in a room where we have outstanding local invites. The user would then get a "no create event in auth events" when trying to reject the invite. We can hack around it by using the dangling invite as the prev event. --- synapse/handlers/room_member.py | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) (limited to 'synapse') diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py index 5a40e8c144..78586a0a1e 100644 --- a/synapse/handlers/room_member.py +++ b/synapse/handlers/room_member.py @@ -469,26 +469,39 @@ class RoomMemberHandler(object): user_id=target.to_string(), room_id=room_id ) # type: Optional[RoomsForUser] if not invite: + logger.info( + "%s sent a leave request to %s, but that is not an active room " + "on this server, and there is no pending invite", + target, + room_id, + ) + raise SynapseError(404, "Not a known room") logger.info( "%s rejects invite to %s from %s", target, room_id, invite.sender ) - if self.hs.is_mine_id(invite.sender): - # the inviter was on our server, but has now left. Carry on - # with the normal rejection codepath. - # - # This is a bit of a hack, because the room might still be - # active on other servers. - pass - else: + if not self.hs.is_mine_id(invite.sender): # send the rejection to the inviter's HS (with fallback to # local event) return await self.remote_reject_invite( invite.event_id, txn_id, requester, content, ) + # the inviter was on our server, but has now left. Carry on + # with the normal rejection codepath, which will also send the + # rejection out to any other servers we believe are still in the room. + + # thanks to overzealous cleaning up of event_forward_extremities in + # `delete_old_current_state_events`, it's possible to end up with no + # forward extremities here. If that happens, let's just hang the + # rejection off the invite event. + # + # see: https://github.com/matrix-org/synapse/issues/7139 + if len(latest_event_ids) == 0: + latest_event_ids = [invite.event_id] + return await self._local_membership_update( requester=requester, target=target, -- cgit 1.4.1