At update of non-LP_NORMAL TID, fail instead of corrupting page header.
authorNoah Misch <noah@leadboat.com>
Sat, 25 Jan 2025 19:28:14 +0000 (11:28 -0800)
committerNoah Misch <noah@leadboat.com>
Sat, 25 Jan 2025 19:28:18 +0000 (11:28 -0800)
commit9311fcb8648075782f59d534010352264bf8dc54
tree93a9116bf2283bff14263b79bdabb6460a0b4844
parent3d57f7cf300540bea6939fe5bdd820a606aa2669
At update of non-LP_NORMAL TID, fail instead of corrupting page header.

The right mix of DDL and VACUUM could corrupt a catalog page header such
that PageIsVerified() durably fails, requiring a restore from backup.
This affects only catalogs that both have a syscache and have DDL code
that uses syscache tuples to construct updates.  One of the test
permutations shows a variant not yet fixed.

This makes !TransactionIdIsValid(TM_FailureData.xmax) possible with
TM_Deleted.  I think core and PGXN are indifferent to that.

Per bug #17821 from Alexander Lakhin.  Back-patch to v13 (all supported
versions).  The test case is v17+, since it uses INJECTION_POINT.

Discussion: https://postgr.es/m/17821-dd8c334263399284@postgresql.org
src/backend/access/heap/heapam.c
src/include/access/tableam.h