From 76a106f264b78b35b4f522e07cca84b90af83f50 Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Thu, 29 Jul 2010 16:15:33 +0000 Subject: [PATCH] Fix possible page corruption by ALTER TABLE .. SET TABLESPACE. If a zeroed page is present in the heap, ALTER TABLE .. SET TABLESPACE will set the LSN and TLI while copying it, which is wrong, and heap_xlog_newpage() will do the same thing during replay, so the corruption propagates to any standby. Note, however, that the bug can't be demonstrated unless archiving is enabled, since in that case we skip WAL logging altogether, and the LSN/TLI are not set. Back-patch to 8.0; prior releases do not have tablespaces. Analysis and patch by Jeff Davis. Adjustments for back-branches and minor wordsmithing by me. --- src/backend/access/heap/heapam.c | 14 +++++++++++--- src/backend/commands/tablecmds.c | 13 ++++++++++--- 2 files changed, 21 insertions(+), 6 deletions(-) diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c index 35ad3d88ac..8a9e13902e 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 1.200.2.3 2006/11/17 18:00:25 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.200.2.4 2010/07/29 16:15:33 rhaas Exp $ * * * INTERFACE ROUTINES @@ -2740,8 +2740,16 @@ heap_xlog_newpage(XLogRecPtr lsn, XLogRecord *record) Assert(record->xl_len == SizeOfHeapNewpage + BLCKSZ); memcpy(page, (char *) xlrec + SizeOfHeapNewpage, BLCKSZ); - PageSetLSN(page, lsn); - PageSetTLI(page, ThisTimeLineID); + /* + * The page may be uninitialized. If so, we can't set the LSN + * and TLI because that would corrupt the page. + */ + if (!PageIsNew(page)) + { + PageSetLSN(page, lsn); + PageSetTLI(page, ThisTimeLineID); + } + LockBuffer(buffer, BUFFER_LOCK_UNLOCK); WriteBuffer(buffer); } diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 59c99fc3e1..8f8d28e825 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.174.2.10 2010/07/01 14:11:03 rhaas Exp $ + * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.174.2.11 2010/07/29 16:15:33 rhaas Exp $ * *------------------------------------------------------------------------- */ @@ -5893,8 +5893,15 @@ copy_relation_data(Relation rel, SMgrRelation dst) recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_NEWPAGE, rdata); - PageSetLSN(page, recptr); - PageSetTLI(page, ThisTimeLineID); + /* + * The page may be uninitialized. If so, we can't set the LSN + * and TLI because that would corrupt the page. + */ + if (!PageIsNew(page)) + { + PageSetLSN(page, recptr); + PageSetTLI(page, ThisTimeLineID); + } END_CRIT_SECTION(); } -- 2.40.0