backups/grapevine
1
0
Fork 0
mirror of https://gitlab.computer.surgery/matrix/grapevine.git synced 2025-12-17 07:41:23 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

tolerate invalid m.direct events when upgrading rooms

Browse source 
Previous behavior was causing us to error out of the entire
state_cache::update_membership function when it saw an invalid m.direct,
making it impossible for affected users to join upgraded rooms. This bug
is especially bad if an affected user attempts to upgrade a room,
because we will fail to create their join event in the new room, leaving
both rooms permanently bricked.

The new behavior should never prevent users from joining a room based on
the contents of their account data, and should migrate the `m.direct`
event in a reasonable way even if it is partially corrupted by the
element bug.

This also fixes a bug where the previous implementation will
unintentionally remove any keys that aren't part of the expected
m.direct schema. I don't know of any cases where this came up in
practice.

Fixes: #46
This commit is contained in:
Benjamin Lee 2024-06-25 17:11:39 -07:00
parent 18360cd3f9
commit a32dc1a3ee
No known key found for this signature in database
GPG key ID: FB9624E2885D55A4
1 changed files with 55 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

86
src/service/rooms/state_cache.rs
View file

@ -4,7 +4,6 @@ use std::{collections::HashSet, sync::Arc};
pub(crate) use data::Data;
use ruma::{
events::{
direct::DirectEvent,
ignored_user_list::IgnoredUserListEvent,
room::{create::RoomCreateEventContent, member::MembershipState},
AnyStrippedStateEvent, AnySyncStateEvent, GlobalAccountDataEventType,
@ -218,39 +217,64 @@ impl Service {
let event_kind = RoomAccountDataEventType::from(
GlobalAccountDataEventType::Direct.to_string(),
);
if let Some(direct_event) = services()
.account_data
.get(
let Some(event) =
services().account_data.get(None, user_id, event_kind.clone())?
else {
return Ok(());
};
let mut event = serde_json::from_str::<serde_json::Value>(event.get())
.expect("RawValue -> Value should always succeed");
// As a server, we should try not to assume anything about the schema
// of this event. Account data may be arbitrary JSON.
//
// In particular, there is an element bug[1] that causes it to store
// m.direct events that don't match the schema from the spec.
//
// [1]: https://github.com/element-hq/element-web/issues/27630
//
// A valid m.direct event looks like this:
//
// {
// "type": "m.account_data",
// "content": {
// "@userid1": [ "!roomid1", "!roomid2" ],
// "@userid2": [ "!roomid3" ],
// }
// }
//
// We want to find userid keys where the value contains from_room_id,
// and insert a new entry for to_room_id. This should work even if some
// of the userid keys do not conform to the spec. If parts of the object
// do not match the expected schema, we should prefer to skip just those
// parts.
let mut event_updated = false;
let Some(direct_user_ids) = event.get_mut("content") else {
return Ok(());
};
let Some(direct_user_ids) = direct_user_ids.as_object_mut() else {
return Ok(());
};
for room_ids in direct_user_ids.values_mut() {
let Some(room_ids) = room_ids.as_array_mut() else {
continue;
};
if room_ids.iter().any(|room_id| room_id == from_room_id.as_str()) {
room_ids.push(to_room_id.to_string().into());
event_updated = true;
}
}
if event_updated {
if let Err(error) = services().account_data.update(
None,
user_id,
event_kind.clone(),
)?
.map(|event| {
serde_json::from_str::<DirectEvent>(event.get())
.map_err(|error| {
warn!(%error, %event_kind, "Invalid account data event");
Error::BadDatabase("Invalid account data event.")
})
})
{
let mut direct_event = direct_event?;
let mut room_ids_updated = false;
for room_ids in direct_event.content.0.values_mut() {
if room_ids.iter().any(|r| r == from_room_id) {
room_ids.push(to_room_id.to_owned());
room_ids_updated = true;
}
}
if room_ids_updated {
services().account_data.update(
None,
user_id,
event_kind,
&serde_json::to_value(&direct_event)
.expect("to json always works"),
)?;
&event,
) {
warn!(%event_kind, %error, "error writing account data event after upgrading room");
}
}
Ok(())