Feedback-ID: i0fe9450f:Fastmail
Date: Fri, 5 Jun 2026 13:53:36 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Andrey Chernyy <andrey.cherny@tantorlabs.com>
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: [PATCH] xml2: Fix stylesheet document leak in xslt_process()
Message-ID: <aiJWUH85UH4nVex_@paquier.xyz>
References: <20260605024642.5a1b6518@andrnote>
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On Fri, Jun 05, 2026 at 02:46:42AM +0300, Andrey Chernyy wrote:
> xslt_process() parses the stylesheet argument with xmlReadMemory(), then
> passes the resulting xmlDoc to xsltParseStylesheetDoc().  On failure,
> libxslt leaves that document owned by the caller, as can be seen from
> its own xsltParseStylesheetFile() wrapper.  Postgres currently cannot
> release it in the error cleanup path because ssdoc is scoped inside the
> PG_TRY block.

In libxslt/xslt.c, the top comment of xsltParseStylesheetDoc() says:
"the doc is automatically freed when the stylesheet is closed."

Reading the code, I can confirm that xsltFreeStylesheet() does a bunch
of stuff, and that it has the idea to call xmlFreeDoc() once at the
end.

Will address this one as well.  Thanks.
--
Michael

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