From: Chao Li <li.evan.chao@gmail.com>
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Subject: Re: Fix unsafe PlannedStmt access in pg_stat_statements
Date: Mon, 11 May 2026 16:11:41 +0800
References: <2F91906A-F2B5-4A6B-9695-D136957D4545@gmail.com>
To: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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> On May 11, 2026, at 16:07, Chao Li <li.evan.chao@gmail.com> wrote:
>=20
> Hi,
>=20
> I spotted this small issue while working on [1].
>=20
> In pgss_ProcessUtility(), there is this comment:
> ```
> /*
> * CAUTION: do not access the *pstmt data structure again below here.
> * If it was a ROLLBACK or similar, that data structure may have been
> * freed.  We must copy everything we still need into local variables,
> * which we did above.
> *
> * For the same reason, we can't risk restoring pstmt->queryId to its
> * former value, which'd otherwise be a good idea.
> */
> ```
>=20
> However, commit 3357471cf9f5e470dfed0c7919bcf31c7efaf2b9 added a new =
access to pstmt after that point:
> ```
> pgss_store(queryString,
>   saved_queryId,
>   saved_stmt_location,
>   saved_stmt_len,
>   PGSS_EXEC,
>   INSTR_TIME_GET_MILLISEC(duration),
>   rows,
>   &bufusage,
>   &walusage,
>   NULL,
>   NULL,
>   0,
>   0,
>   pstmt->planOrigin);
> ```
>=20
> The attached patch fixes this by saving pstmt->planOrigin, following =
the same pattern already used for queryId, stmt_location, and stmt_len.
>=20
> [1] =
https://www.postgresql.org/message-id/8ED8C22D-54CD-4EC4-B53C-D39F935FA83D=
%40gmail.com
>=20
> Best regards,
> --
> Chao Li (Evan)
> HighGo Software Co., Ltd.
> https://www.highgo.com/
>=20

Oops! Forgot the attachment.

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/


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contrib/pg_stat_statements/pg_stat_statements.c=20|=203=20++-=0A=201=20=
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pgss_enabled(nesting_level);=0A=20=0A=20=09/*=0A@@=20-1210,7=20+1211,7=20=
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