Prevent local user profiles leaking when a "per-room profile" is changed

synapse/handlers/user_directory.py

@@ -236,7 +236,7 @@ async def _handle_deltas(self, deltas: List[Dict[str, Any]]) -> None:
                 if joined is MatchChange.no_change:
                     # Handle any profile changes for remote users
                     if not self.is_mine_id(state_key):
-                        await self._handle_profile_change(
+                        await self._handle_possible_remote_profile_change(
                             state_key, room_id, prev_event_id, event_id
                         )
 
@@ -341,11 +341,13 @@ async def _handle_new_user(
             room_id: The room ID that user joined or started being public
             user_id
         """
-        logger.debug("Adding new user to dir, %r", user_id)
-
-        await self.store.update_profile_in_user_dir(
-            user_id, profile.display_name, profile.avatar_url
-        )
+        # Local users' directory entries are created and updated in tandem with
+        # their global profile, not in response to room events.
+        if not self.is_mine_id(user_id):
+            logger.debug("Adding new user to dir, %r", user_id)
+            await self.store.update_profile_in_user_dir(
+                user_id, profile.display_name, profile.avatar_url
+            )
 
         is_public = await self.store.is_room_world_readable_or_publicly_joinable(
             room_id
@@ -405,7 +407,7 @@ async def _handle_remove_user(self, room_id: str, user_id: str) -> None:
         if len(rooms_user_is_in) == 0:
             await self.store.remove_from_user_dir(user_id)
 
-    async def _handle_profile_change(
+    async def _handle_possible_remote_profile_change(
         self,
         user_id: str,
         room_id: str,