mirrors/postgres
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Check syscache result in AlterStatistics

Browse Source 
The syscache lookup may return NULL even for valid OID, for example due
to a concurrent DROP STATISTICS, so a HeapTupleIsValid is necessary.
Without it, it may fail with a segfault.

Reported by Alexander Lakhin, patch by me. Backpatch to 13, where ALTER
STATISTICS ... SET STATISTICS was introduced.

Backpatch-through: 13
Discussion: https://postgr.es/m/17372-bf3b6e947e35ae77%40postgresql.org
This commit is contained in:
Tomas Vondra 2022-01-23 02:49:41 +01:00
parent 31b7b4d26e
commit 267ccc38ba
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/backend/commands/statscmds.c
View File

@ -493,6 +493,8 @@ AlterStatistics(AlterStatsStmt *stmt)
rel = table_open(StatisticExtRelationId, RowExclusiveLock);
oldtup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(stxoid));
if (!HeapTupleIsValid(oldtup))
elog(ERROR, "cache lookup failed for extended statistics object %u", stxoid);
/* Must be owner of the existing statistics object */
if (!pg_statistics_object_ownercheck(stxoid, GetUserId()))