From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
---|---|
To: | pgsql-committers(at)lists(dot)postgresql(dot)org |
Subject: | pgsql: pg_stat_statements: fetch stmt location/length before it disappe |
Date: | 2022-11-01 16:48:22 |
Message-ID: | E1opuR4-001lkw-7I@gemulon.postgresql.org |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-committers |
pg_stat_statements: fetch stmt location/length before it disappears.
When executing a utility statement, we must fetch everything
we need out of the PlannedStmt data structure before calling
standard_ProcessUtility. In certain cases (possibly only ROLLBACK
in extended query protocol), that data structure will get freed
during command execution. The situation is probably often harmless
in production builds, but in debug builds we intentionally overwrite
the freed memory with garbage, leading to picking up garbage values
of statement location and length, typically causing an assertion
failure later in pg_stat_statements. In non-debug builds, if
something did go wrong it would likely lead to storing garbage
for the query string.
Report and fix by zhaoqigui (with cosmetic adjustments by me).
It's an old problem, so back-patch to all supported versions.
Discussion: https://postgr.es/m/17663-a344fd0675f92128@postgresql.org
Discussion: https://postgr.es/m/1667307420050.56657@hundsun.com
Branch
------
REL_15_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/8b0a5cf3fe48a929b26e6e305f0765cf383d2ade
Modified Files
--------------
contrib/pg_stat_statements/pg_stat_statements.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2022-11-01 18:34:56 | pgsql: Fix planner failure with extended statistics on partitioned tabl |
Previous Message | Peter Eisentraut | 2022-11-01 13:21:31 | pgsql: doc: Add note about lack of publication privileges |