From 62938d6cc84f3f4b1b3cf90af3a4b6303cacf6c2 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 2 May 2010 22:28:11 +0000 Subject: [PATCH] Fix replay of XLOG_HEAP_NEWPAGE WAL records to pay attention to the forknum field of the WAL record. The previous coding always wrote to the main fork, resulting in data corruption if the page was meant to go into a non-default fork. At present, the only operation that can produce such WAL records is ALTER TABLE/INDEX SET TABLESPACE when executed with archive_mode = on. Data corruption would be observed on standby slaves, and could occur on the master as well if a database crash and recovery occurred after committing the ALTER and before the next checkpoint. Per report from Gordon Shannon. Back-patch to 8.4; the problem doesn't exist in earlier branches because we didn't have a concept of multiple relation forks then. --- src/backend/access/heap/heapam.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 0f04f845cf..e87e096419 100644 --- a/src/backend/access/heap/heapam.c +++ b/src/backend/access/heap/heapam.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.277.2.1 2009/08/24 02:18:40 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.277.2.2 2010/05/02 22:28:11 tgl Exp $ * * * INTERFACE ROUTINES @@ -4195,8 +4195,10 @@ heap_xlog_newpage(XLogRecPtr lsn, XLogRecord *record) * Note: the NEWPAGE log record is used for both heaps and indexes, so do * not do anything that assumes we are touching a heap. */ - buffer = XLogReadBuffer(xlrec->node, xlrec->blkno, true); + buffer = XLogReadBufferExtended(xlrec->node, xlrec->forknum, xlrec->blkno, + RBM_ZERO); Assert(BufferIsValid(buffer)); + LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE); page = (Page) BufferGetPage(buffer); Assert(record->xl_len == SizeOfHeapNewpage + BLCKSZ);