s4-server: Open and close a transaction on sam.ldb at startup

[samba.git] / source4 / smbd / server.c

diff --git a/source4/smbd/server.c b/source4/smbd/server.c
index ea421b3bd68811ed8e4fe4163b6241a7e2946061..badc21270c08b90081719b7981676bd09abaad9c 100644 (file)
--- a/source4/smbd/server.c
+++ b/source4/smbd/server.c
@@ -230,6 +230,41 @@ _NORETURN_ static void max_runtime_handler(struct tevent_context *ev,
        exit(0);
 }
 
+/*
+ * When doing an in-place upgrade of Samba, the database format may have
+ * changed between versions. E.g. between 4.7 and 4.8 the DB changed from
+ * DN-based indexes to GUID-based indexes, so we have to re-index the DB after
+ * upgrading.
+ * This function handles migrating an older samba DB to a new Samba release.
+ * Note that we have to maintain DB compatibility between *all* older versions
+ * of Samba, not just the ones still under maintenance support.
+ */
+static int handle_inplace_db_upgrade(struct ldb_context *ldb_ctx)
+{
+       int ret;
+
+       /*
+        * The DSDB stack will handle reindexing the DB (if needed) upon the first
+        * DB write. Open and close a transaction on the DB now to trigger a
+        * reindex if required, rather than waiting for the first write.
+        * We do this here to guarantee that the DB will have been re-indexed by
+        * the time the main samba code runs.
+        * Refer to dsdb_schema_set_indices_and_attributes() for the actual reindexing
+        * code, called from
+        * source4/dsdb/samdb/ldb_modules/schema_load.c:schema_load_start_transaction()
+        */
+       ret = ldb_transaction_start(ldb_ctx);
+       if (ret != LDB_SUCCESS) {
+               return ret;
+       }
+
+       ret = ldb_transaction_commit(ldb_ctx);
+       if (ret != LDB_SUCCESS) {
+               return ret;
+       }
+       return LDB_SUCCESS;
+}
+
 /*
   pre-open the key databases. This saves a lot of time in child
   processes
@@ -262,6 +297,13 @@ static int prime_ldb_databases(struct tevent_context *event_ctx, bool *am_backup
                talloc_free(db_context);
                return LDB_ERR_OPERATIONS_ERROR;
        }
+
+       ret = handle_inplace_db_upgrade(ldb_ctx);
+       if (ret != LDB_SUCCESS) {
+               talloc_free(db_context);
+               return ret;
+       }
+
        pdb = privilege_connect(db_context, cmdline_lp_ctx);
        if (pdb == NULL) {
                talloc_free(db_context);