Feedback-ID: i0fe9450f:Fastmail
Date: Thu, 15 Jun 2023 13:53:36 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Alexander Lakhin <exclusion@gmail.com>
Cc: Richard Guo <guofenglinux@gmail.com>,
	Ankit Kumar Pandey <itsankitkp@gmail.com>,
	David Rowley <dgrowleyml@gmail.com>,
	Teodor Sigaev <teodor@sigaev.ru>, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #17888: Incorrect memory access in gist__int_ops for an
 input array with many elements
Message-ID: <ZIqZUKZ/PpMfbqXT@paquier.xyz>
References: <17888-f72930e6b5ce8c14@postgresql.org>
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 <ZIlAVBmmAhVaVGHR@paquier.xyz>
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On Wed, Jun 14, 2023 at 01:21:40PM +0900, Michael Paquier wrote:
> Likely that's something we'd better backpatch, to avoid people playing
> with that too much in the back-branches.  Thoughts or objections?

Well, we could perhaps revisit the choice of 08ee64e to remove the
LEAF flag from the data stored.  However, seeing the lack of
complaints for the past 18 years with users storing large arrays under
gist__int_ops, spending more time on this is not really appealing,
either.  Or we would have heard about that because the decompression
immediately breaks for this case.

I have spent some time on that today, and applied what has been
suggested to restrict the usage of this operator when inserting data=20
for a leaf page, so as the decompression does not get crazy when
retrieving the contents of the leaf pages.
--
Michael

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