diff --git a/changelog.d/15300.bugfix b/changelog.d/15300.bugfix
new file mode 100644
index 0000000000..8f29b08444
--- /dev/null
+++ b/changelog.d/15300.bugfix
@@ -0,0 +1 @@
+Fix a bug in which the [`POST /_matrix/client/v3/rooms/{roomId}/report/{eventId}`](https://spec.matrix.org/v1.6/client-server-api/#post_matrixclientv3roomsroomidreporteventid) endpoint would return the wrong error if the user did not have permission to view the event. This aligns Synapse's implementation with [MSC2249](https://github.com/matrix-org/matrix-spec-proposals/pull/2249).
\ No newline at end of file
diff --git a/docs/upgrade.md b/docs/upgrade.md
index f06e874054..f14444a400 100644
--- a/docs/upgrade.md
+++ b/docs/upgrade.md
@@ -88,6 +88,18 @@ process, for example:
dpkg -i matrix-synapse-py3_1.3.0+stretch1_amd64.deb
```
+# Upgrading to v1.80.0
+
+## Reporting events error code change
+
+Before this update, the
+[`POST /_matrix/client/v3/rooms/{roomId}/report/{eventId}`](https://spec.matrix.org/v1.6/client-server-api/#post_matrixclientv3roomsroomidreporteventid)
+endpoint would return a `403` if a user attempted to report an event that they did not have access to.
+This endpoint will now return a `404` in this case instead.
+
+Clients that implement event reporting should check that their error handling code will handle this
+change.
+
# Upgrading to v1.79.0
## The `on_threepid_bind` module callback method has been deprecated
diff --git a/synapse/rest/client/report_event.py b/synapse/rest/client/report_event.py
index 9be5860221..ac1a63ca27 100644
--- a/synapse/rest/client/report_event.py
+++ b/synapse/rest/client/report_event.py
@@ -16,7 +16,7 @@ import logging
from http import HTTPStatus
from typing import TYPE_CHECKING, Tuple
-from synapse.api.errors import Codes, NotFoundError, SynapseError
+from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
from synapse.http.server import HttpServer
from synapse.http.servlet import RestServlet, parse_json_object_from_request
from synapse.http.site import SynapseRequest
@@ -62,12 +62,18 @@ class ReportEventRestServlet(RestServlet):
Codes.BAD_JSON,
)
- event = await self._event_handler.get_event(
- requester.user, room_id, event_id, show_redacted=False
- )
+ try:
+ event = await self._event_handler.get_event(
+ requester.user, room_id, event_id, show_redacted=False
+ )
+ except AuthError:
+ # The event exists, but this user is not allowed to access this event.
+ event = None
+
if event is None:
raise NotFoundError(
- "Unable to report event: it does not exist or you aren't able to see it."
+ "Unable to report event: "
+ "it does not exist or you aren't able to see it."
)
await self.store.add_event_report(
diff --git a/synapse/storage/databases/main/events_worker.py b/synapse/storage/databases/main/events_worker.py
index 20b7a68362..0cf46626d2 100644
--- a/synapse/storage/databases/main/events_worker.py
+++ b/synapse/storage/databases/main/events_worker.py
@@ -805,7 +805,6 @@ class EventsWorkerStore(SQLBaseStore):
# the events have been redacted, and if so pulling the redaction event
# out of the database to check it.
#
- missing_events = {}
try:
# Try to fetch from any external cache. We already checked the
# in-memory cache above.
diff --git a/tests/rest/client/test_report_event.py b/tests/rest/client/test_report_event.py
index 1a8ab067a9..b88f1d61a0 100644
--- a/tests/rest/client/test_report_event.py
+++ b/tests/rest/client/test_report_event.py
@@ -90,6 +90,43 @@ class ReportEventTestCase(unittest.HomeserverTestCase):
msg=channel.result["body"],
)
+ def test_cannot_report_event_if_not_in_room(self) -> None:
+ """
+ Tests that we don't accept event reports for events that exist, but for which
+ the reporter should not be able to view (because they are not in the room).
+ """
+ # Have the admin user create a room (the "other" user will not join this room).
+ new_room_id = self.helper.create_room_as(tok=self.admin_user_tok)
+
+ # Have the admin user send an event in this room.
+ response = self.helper.send_event(
+ new_room_id,
+ "m.room.message",
+ content={
+ "msgtype": "m.text",
+ "body": "This event has some bad words in it! Flip!",
+ },
+ tok=self.admin_user_tok,
+ )
+ event_id = response["event_id"]
+
+ # Have the "other" user attempt to report it. Perhaps they found the event ID
+ # in a screenshot or something...
+ channel = self.make_request(
+ "POST",
+ f"rooms/{new_room_id}/report/{event_id}",
+ {"reason": "I'm not in this room but I have opinions anyways!"},
+ access_token=self.other_user_tok,
+ )
+
+ # The "other" user is not in the room, so their report should be rejected.
+ self.assertEqual(404, channel.code, msg=channel.result["body"])
+ self.assertEqual(
+ "Unable to report event: it does not exist or you aren't able to see it.",
+ channel.json_body["error"],
+ msg=channel.result["body"],
+ )
+
def _assert_status(self, response_status: int, data: JsonDict) -> None:
channel = self.make_request(
"POST", self.report_path, data, access_token=self.other_user_tok
|
