Fix locking bugs that could corrupt pg_control.

Thomas Munro <tmunro@postgresql.org>

Commit: 09dc17486393563a680400908b33061ada5826f5
Author: Thomas Munro <tmunro@postgresql.org>
Date: 2020-06-08T02:02:20Z
Releases: 9.5.23
Fix locking bugs that could corrupt pg_control.

The redo routines for XLOG_CHECKPOINT_{ONLINE,SHUTDOWN} must acquire
ControlFileLock before modifying ControlFile->checkPointCopy, or the
checkpointer could write out a control file with a bad checksum.

Likewise, XLogReportParameters() must acquire ControlFileLock before
modifying ControlFile and calling UpdateControlFile().

Back-patch to all supported releases.

Author: Nathan Bossart <bossartn@amazon.com>
Author: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/70BF24D6-DC51-443F-B55A-95735803842A%40amazon.com

Files

PathChange+/−
src/backend/access/transam/xlog.c modified +8 −0

Discussion