From: Fujii Masao <fujii@postgresql.org>
Date: Tue, 12 Jul 2022 02:53:29 +0000 (+0900)
Subject: Fix assertion failure and segmentation fault in backup code.
X-Git-Tag: REL_10_22~23
X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=2497d2b770916f802353f3bf5e03d42c4c98d3cf;p=postgresql.git

Fix assertion failure and segmentation fault in backup code.

When a non-exclusive backup is canceled, do_pg_abort_backup() is called
and resets some variables set by pg_backup_start (pg_start_backup in v14
or before). But previously it forgot to reset the session state indicating
whether a non-exclusive backup is in progress or not in this session.

This issue could cause an assertion failure when the session running
BASE_BACKUP is terminated after it executed pg_backup_start and
pg_backup_stop (pg_stop_backup in v14 or before). Also it could cause
a segmentation fault when pg_backup_stop is called after BASE_BACKUP
in the same session is canceled.

This commit fixes the issue by making do_pg_abort_backup reset
that session state.

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
---

diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 414b7d2dcc0..ef5ce8c1caa 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -11484,6 +11484,8 @@ do_pg_abort_backup(void)
 	{
 		XLogCtl->Insert.forcePageWrites = false;
 	}
+
+	sessionBackupState = SESSION_BACKUP_NONE;
 	WALInsertLockRelease();
 }