From 116b4ebe813edee660b63309004ff8ffe14c533c Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Tue, 12 Jul 2022 09:31:57 +0900 Subject: [PATCH] Prevent BASE_BACKUP in the middle of another backup in the same session. Multiple non-exclusive backups are able to be run conrrently in different sessions. But, in the same session, only one non-exclusive backup can be run at the same moment. If pg_backup_start (pg_start_backup in v14 or before) is called in the middle of another non-exclusive backup in the same session, an error is thrown. However, previously, in logical replication walsender mode, even if that walsender session had already called pg_backup_start and started a non-exclusive backup, it could execute BASE_BACKUP command and start another non-exclusive backup. Which caused subsequent pg_backup_stop to throw an error because BASE_BACKUP unexpectedly reset the session state marked by pg_backup_start. This commit prevents BASE_BACKUP command in the middle of another non-exclusive backup in the same session. Back-patch to all supported branches. Author: Fujii Masao Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Michael Paquier, Robert Haas Discussion: https://postgr.es/m/3374718f-9fbf-a950-6d66-d973e027f44c@oss.nttdata.com --- src/backend/replication/basebackup.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/backend/replication/basebackup.c b/src/backend/replication/basebackup.c index e09108d0ec..d142cc2131 100644 --- a/src/backend/replication/basebackup.c +++ b/src/backend/replication/basebackup.c @@ -932,6 +932,12 @@ void SendBaseBackup(BaseBackupCmd *cmd) { basebackup_options opt; + SessionBackupState status = get_backup_status(); + + if (status == SESSION_BACKUP_NON_EXCLUSIVE) + ereport(ERROR, + (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), + errmsg("a backup is already in progress in this session"))); parse_basebackup_options(cmd->options, &opt); -- 2.36.0