]> 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)
commit011eedcdc3fe04000c46881333aaa0ac70a1aa1f
tree09bd49245f0cc9b6cd88ef751a0ad20af453d5d8
parent2aa6be6e64812ab3421b506c20b0e15078160e75
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