From 92eac974b95c06868768f39f642361246f1c0b0f Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Tue, 31 Dec 2019 10:41:44 +0000 Subject: [PATCH] Hacks to work around #6605 (#6608) When we have an event which refers to non-existent auth_events, ignore said events rather than exploding in a ball of fire. Fixes #6605. --- changelog.d/6608.bugfix | 1 + synapse/state/v2.py | 52 +++++++++++++++++++++++++++++------------ 2 files changed, 38 insertions(+), 15 deletions(-) create mode 100644 changelog.d/6608.bugfix diff --git a/changelog.d/6608.bugfix b/changelog.d/6608.bugfix new file mode 100644 index 000000000..7768e0846 --- /dev/null +++ b/changelog.d/6608.bugfix @@ -0,0 +1 @@ +Fix exceptions caused by state resolution choking on malformed events. diff --git a/synapse/state/v2.py b/synapse/state/v2.py index cb77ed5b7..72fb8a631 100644 --- a/synapse/state/v2.py +++ b/synapse/state/v2.py @@ -183,16 +183,20 @@ def _get_power_level_for_sender(room_id, event_id, event_map, state_res_store): pl = None for aid in event.auth_event_ids(): - aev = yield _get_event(room_id, aid, event_map, state_res_store) - if (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""): + aev = yield _get_event( + room_id, aid, event_map, state_res_store, allow_none=True + ) + if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""): pl = aev break if pl is None: # Couldn't find power level. Check if they're the creator of the room for aid in event.auth_event_ids(): - aev = yield _get_event(room_id, aid, event_map, state_res_store) - if (aev.type, aev.state_key) == (EventTypes.Create, ""): + aev = yield _get_event( + room_id, aid, event_map, state_res_store, allow_none=True + ) + if aev and (aev.type, aev.state_key) == (EventTypes.Create, ""): if aev.content.get("creator") == event.sender: return 100 break @@ -403,10 +407,17 @@ def _iterative_auth_checks( auth_events = {} for aid in event.auth_event_ids(): - ev = yield _get_event(room_id, aid, event_map, state_res_store) + ev = yield _get_event( + room_id, aid, event_map, state_res_store, allow_none=True + ) - if ev.rejected_reason is None: - auth_events[(ev.type, ev.state_key)] = ev + if not ev: + logger.warning( + "auth_event id %s for event %s is missing", aid, event_id + ) + else: + if ev.rejected_reason is None: + auth_events[(ev.type, ev.state_key)] = ev for key in event_auth.auth_types_for_event(event): if key in resolved_state: @@ -457,8 +468,10 @@ def _mainline_sort( auth_events = pl_ev.auth_event_ids() pl = None for aid in auth_events: - ev = yield _get_event(room_id, aid, event_map, state_res_store) - if (ev.type, ev.state_key) == (EventTypes.PowerLevels, ""): + ev = yield _get_event( + room_id, aid, event_map, state_res_store, allow_none=True + ) + if ev and (ev.type, ev.state_key) == (EventTypes.PowerLevels, ""): pl = aid break @@ -506,8 +519,10 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor event = None for aid in auth_events: - aev = yield _get_event(room_id, aid, event_map, state_res_store) - if (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""): + aev = yield _get_event( + room_id, aid, event_map, state_res_store, allow_none=True + ) + if aev and (aev.type, aev.state_key) == (EventTypes.PowerLevels, ""): event = aev break @@ -516,7 +531,7 @@ def _get_mainline_depth_for_event(event, mainline_map, event_map, state_res_stor @defer.inlineCallbacks -def _get_event(room_id, event_id, event_map, state_res_store): +def _get_event(room_id, event_id, event_map, state_res_store, allow_none=False): """Helper function to look up event in event_map, falling back to looking it up in the store @@ -525,15 +540,22 @@ def _get_event(room_id, event_id, event_map, state_res_store): event_id (str) event_map (dict[str,FrozenEvent]) state_res_store (StateResolutionStore) + allow_none (bool): if the event is not found, return None rather than raising + an exception Returns: - Deferred[FrozenEvent] + Deferred[Optional[FrozenEvent]] """ if event_id not in event_map: events = yield state_res_store.get_events([event_id], allow_rejected=True) event_map.update(events) - event = event_map[event_id] - assert event is not None + event = event_map.get(event_id) + + if event is None: + if allow_none: + return None + raise Exception("Unknown event %s" % (event_id,)) + if event.room_id != room_id: raise Exception( "In state res for room %s, event %s is in %s"