]> git.ipfire.org Git - thirdparty/postgresql.git/commit
Fix unsafe order of operations in ResourceOwnerReleaseAll().
authorTom Lane <tgl@sss.pgh.pa.us>
Mon, 22 Jun 2026 22:03:23 +0000 (18:03 -0400)
committerTom Lane <tgl@sss.pgh.pa.us>
Mon, 22 Jun 2026 22:03:23 +0000 (18:03 -0400)
commitac6a58a700da1262d669e970f7ccba66f916c412
tree8c597503bc9196225c77ae01c80f661a8398baa9
parent020426268ff6acaa140780336eb1c50b034cb893
Fix unsafe order of operations in ResourceOwnerReleaseAll().

This function called the resource-kind-specific ReleaseResource()
method for each item before deleting that item from the resowner.
That's backwards from the ordering in ResourceOwnerReleaseAllOfKind,
and it's not very safe.  If ReleaseResource throws an error then the
subsequent abort cleanup will come back here and try to release that
item again, possibly leading to a double-free or similar crash,
and in any case risking an infinite error cleanup loop.  This mistake
explains why the pgcrypto bug just fixed in 80bb0ebcc led to a crash
rather than something more benign.

Remove the item from the resowner, then call ReleaseResource,
matching the way things were done before b8bff07da.  If there
is a problem of this sort, we'd prefer to leak the item than
suffer the other likely consequences.

Per further analysis of bug #19527.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/646741.1782157515@sss.pgh.pa.us
Backpatch-through: 17
src/backend/utils/resowner/resowner.c