Additional error checking.

synapse/federation/federation_client.py

@@ -1332,14 +1332,28 @@ async def send_request(
             if not isinstance(room, dict):
                 raise InvalidResponseError("'room' must be a dict")
 
-            # TODO Validate children_state of the room.
+            # Validate children_state of the room.
+            children_state = room.get("children_state", [])
+            if not isinstance(children_state, Sequence):
+                raise InvalidResponseError("'room.children_state' must be a list")
+            if any(not isinstance(e, dict) for e in children_state):
+                raise InvalidResponseError("Invalid event in 'children_state' list")
+            try:
+                [
+                    FederationSpaceSummaryEventResult.from_json_dict(e)
+                    for e in children_state
+                ]
+            except ValueError as e:
+                raise InvalidResponseError(str(e))
 
+            # Validate the children rooms.
             children = res.get("children", [])
             if not isinstance(children, Sequence):
                 raise InvalidResponseError("'children' must be a list")
             if any(not isinstance(r, dict) for r in children):
                 raise InvalidResponseError("Invalid room in 'children' list")
 
+            # Validate the inaccessible children.
             inaccessible_children = res.get("inaccessible_children", [])
             if not isinstance(inaccessible_children, Sequence):
                 raise InvalidResponseError("'inaccessible_children' must be a list")

synapse/handlers/space_summary.py

@@ -412,7 +412,8 @@ async def _get_room_hierarchy(
                             children_room_entries.get(ev["state_key"]),
                         )
                         for ev in reversed(room_entry.children)
-                        if ev["state_key"] not in inaccessible_children
+                        if ev["type"] == EventTypes.SpaceChild
+                        and ev["state_key"] not in inaccessible_children
                     )
 
         result: JsonDict = {"rooms": rooms_result}

tests/handlers/test_space_summary.py

@@ -458,7 +458,7 @@ def test_pagination(self):
         self.assertNotIn("next_token", result)
 
     def test_invalid_pagination_token(self):
-        """"""
+        """An invalid pagination token, or changing other parameters, shoudl be rejected."""
         room_ids = []
         for i in range(1, 10):
             room = self.helper.create_room_as(self.user, tok=self.token)
@@ -575,6 +575,7 @@ def test_fed_complex(self):
             },
             [
                 {
+                    "type": EventTypes.SpaceChild,
                     "room_id": subspace,
                     "state_key": subroom,
                     "content": {"via": [fed_hostname]},
@@ -731,6 +732,7 @@ def test_fed_filtering(self):
             # Place each room in the sub-space.
             [
                 {
+                    "type": EventTypes.SpaceChild,
                     "room_id": subspace,
                     "state_key": room_id,
                     "content": {"via": [fed_hostname]},