diff options
| -rw-r--r-- | changelog.d/12087.bugfix | 1 | ||||
| -rw-r--r-- | synapse/federation/federation_server.py | 7 | ||||
| -rw-r--r-- | synapse/handlers/federation.py | 61 |
3 files changed, 25 insertions, 44 deletions
diff --git a/changelog.d/12087.bugfix b/changelog.d/12087.bugfix new file mode 100644 index 0000000000..6dacdddd0d --- /dev/null +++ b/changelog.d/12087.bugfix @@ -0,0 +1 @@ +Fix a long-standing bug which caused the `/_matrix/federation/v1/state` and `.../state_ids` endpoints to return incorrect or invalid data when called for an event which we have stored as an "outlier". diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py index 482bbdd867..af2d0f7d79 100644 --- a/synapse/federation/federation_server.py +++ b/synapse/federation/federation_server.py @@ -22,7 +22,6 @@ from typing import ( Callable, Collection, Dict, - Iterable, List, Optional, Tuple, @@ -577,10 +576,10 @@ class FederationServer(FederationBase): async def _on_context_state_request_compute( self, room_id: str, event_id: Optional[str] ) -> Dict[str, list]: + pdus: Collection[EventBase] if event_id: - pdus: Iterable[EventBase] = await self.handler.get_state_for_pdu( - room_id, event_id - ) + event_ids = await self.handler.get_state_ids_for_pdu(room_id, event_id) + pdus = await self.store.get_events_as_list(event_ids) else: pdus = (await self.state.get_current_state(room_id)).values() diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py index db39aeabde..350ec9c03a 100644 --- a/synapse/handlers/federation.py +++ b/synapse/handlers/federation.py @@ -950,54 +950,35 @@ class FederationHandler: return event - async def get_state_for_pdu(self, room_id: str, event_id: str) -> List[EventBase]: - """Returns the state at the event. i.e. not including said event.""" - - event = await self.store.get_event(event_id, check_room_id=room_id) - - state_groups = await self.state_store.get_state_groups(room_id, [event_id]) - - if state_groups: - _, state = list(state_groups.items()).pop() - results = {(e.type, e.state_key): e for e in state} - - if event.is_state(): - # Get previous state - if "replaces_state" in event.unsigned: - prev_id = event.unsigned["replaces_state"] - if prev_id != event.event_id: - prev_event = await self.store.get_event(prev_id) - results[(event.type, event.state_key)] = prev_event - else: - del results[(event.type, event.state_key)] - - res = list(results.values()) - return res - else: - return [] - async def get_state_ids_for_pdu(self, room_id: str, event_id: str) -> List[str]: """Returns the state at the event. i.e. not including said event.""" event = await self.store.get_event(event_id, check_room_id=room_id) + if event.internal_metadata.outlier: + raise NotFoundError("State not known at event %s" % (event_id,)) state_groups = await self.state_store.get_state_groups_ids(room_id, [event_id]) - if state_groups: - _, state = list(state_groups.items()).pop() - results = state + # get_state_groups_ids should return exactly one result + assert len(state_groups) == 1 - if event.is_state(): - # Get previous state - if "replaces_state" in event.unsigned: - prev_id = event.unsigned["replaces_state"] - if prev_id != event.event_id: - results[(event.type, event.state_key)] = prev_id - else: - results.pop((event.type, event.state_key), None) + state_map = next(iter(state_groups.values())) - return list(results.values()) - else: - return [] + state_key = event.get_state_key() + if state_key is not None: + # the event was not rejected (get_event raises a NotFoundError for rejected + # events) so the state at the event should include the event itself. + assert ( + state_map.get((event.type, state_key)) == event.event_id + ), "State at event did not include event itself" + + # ... but we need the state *before* that event + if "replaces_state" in event.unsigned: + prev_id = event.unsigned["replaces_state"] + state_map[(event.type, state_key)] = prev_id + else: + del state_map[(event.type, state_key)] + + return list(state_map.values()) async def on_backfill_request( self, origin: str, room_id: str, pdu_list: List[str], limit: int |