Fix get|set_type_stream_id_for_appservice store functions (#8648)

1 files changed, 22 insertions, 7 deletions

diff --git a/synapse/storage/databases/main/appservice.py b/synapse/storage/databases/main/appservice.py
index 43bf0f649a..637a938bac 100644
--- a/synapse/storage/databases/main/appservice.py
+++ b/synapse/storage/databases/main/appservice.py
@@ -369,17 +369,25 @@ class ApplicationServiceTransactionWorkerStore(
     async def get_type_stream_id_for_appservice(
         self, service: ApplicationService, type: str
     ) -> int:
+        if type not in ("read_receipt", "presence"):
+            raise ValueError(
+                "Expected type to be a valid application stream id type, got %s"
+                % (type,)
+            )
+
         def get_type_stream_id_for_appservice_txn(txn):
             stream_id_type = "%s_stream_id" % type
             txn.execute(
-                "SELECT ? FROM application_services_state WHERE as_id=?",
-                (stream_id_type, service.id,),
+                # We do NOT want to escape `stream_id_type`.
+                "SELECT %s FROM application_services_state WHERE as_id=?"
+                % stream_id_type,
+                (service.id,),
             )
-            last_txn_id = txn.fetchone()
-            if last_txn_id is None or last_txn_id[0] is None:  # no row exists
+            last_stream_id = txn.fetchone()
+            if last_stream_id is None or last_stream_id[0] is None:  # no row exists
                 return 0
             else:
-                return int(last_txn_id[0])
+                return int(last_stream_id[0])
 
         return await self.db_pool.runInteraction(
             "get_type_stream_id_for_appservice", get_type_stream_id_for_appservice_txn
@@ -388,11 +396,18 @@ class ApplicationServiceTransactionWorkerStore(
     async def set_type_stream_id_for_appservice(
         self, service: ApplicationService, type: str, pos: int
     ) -> None:
+        if type not in ("read_receipt", "presence"):
+            raise ValueError(
+                "Expected type to be a valid application stream id type, got %s"
+                % (type,)
+            )
+
         def set_type_stream_id_for_appservice_txn(txn):
             stream_id_type = "%s_stream_id" % type
             txn.execute(
-                "UPDATE ? SET device_list_stream_id = ? WHERE as_id=?",
-                (stream_id_type, pos, service.id),
+                "UPDATE application_services_state SET %s = ? WHERE as_id=?"
+                % stream_id_type,
+                (pos, service.id),
             )
 
         await self.db_pool.runInteraction(