agora inbox for pgsql-committers@postgresql.org
help / color / mirror / Atom feedFrom: Fujii Masao <fujii@postgresql.org>
To: pgsql-committers@lists.postgresql.org
Subject: pgsql: Check CREATE_REPLICATION_SLOT response shape in libpqwalreceiver
Date: Thu, 16 Jul 2026 04:41:24 +0000
Message-ID: <E1wkDuV-000ObQ-3C@gemulon.postgresql.org> (raw)
Check CREATE_REPLICATION_SLOT response shape in libpqwalreceiver
Previously, libpqrcv_create_slot() checked only that
CREATE_REPLICATION_SLOT returned PGRES_TUPLES_OK before reading
values from the first row. If the server unexpectedly returned an
invalid result, such as zero rows, PQgetvalue() could return NULL,
leading to a crash while parsing the LSN.
Other replication commands, such as IDENTIFY_SYSTEM, already validate
the response shape before accessing result values, but
CREATE_REPLICATION_SLOT did not.
Fix this by verifying that CREATE_REPLICATION_SLOT response contains
exactly one row with four fields, and report a protocol violation otherwise.
Backpatch to all supported versions.
Bug: #19547
Reported-by: Yuelin Wang <1217816127@qq.com>
Author: Kenny Chen <kennychen851228@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/19547-f7986f668f71e788@postgresql.org
Discussion: https://postgr.es/m/CAPXstDtW2iqe+DJAOTQTX+rRziJp2UhZSo1+HRj1COAtbu+nKw@mail.gmail.com
Backpatch-through: 14
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/3cf5264557bee2ba848e5276beecc10571d468a6
Modified Files
--------------
src/backend/replication/libpqwalreceiver/libpqwalreceiver.c | 8 ++++++++
1 file changed, 8 insertions(+)
view thread (7+ messages) latest in thread
Message-ID: <E1wkDuV-000ObQ-3C@gemulon.postgresql.org>
Permalink: ../E1wkDuV-000ObQ-3C@gemulon.postgresql.org/
Also on: postgresql.org/message-id/E1wkDuV-000ObQ-3C@gemulon.postgresql.org
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-committers@postgresql.org
Cc: fujii@postgresql.org, pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Check CREATE_REPLICATION_SLOT response shape in libpqwalreceiver
In-Reply-To: <E1wkDuV-000ObQ-3C@gemulon.postgresql.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox