Horton

Re: glibc qsort() vulnerability

Mats Kindahl <mats@timescale.com>

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From: Mats Kindahl <mats@timescale.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Nathan Bossart <nathandbossart@gmail.com>, Andres Freund <andres@anarazel.de>, Thomas Munro <thomas.munro@gmail.com>, Heikki Linnakangas <hlinnaka@iki.fi>, pgsql-hackers@lists.postgresql.org
Date: 2024-02-09T19:35:57Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Use new overflow-safe integer comparison functions.

  2. Introduce overflow-safe integer comparison functions.

  3. Replace calls to pg_qsort() with the qsort() macro.

  4. Switch over to using our own qsort() all the time, as has been proposed

On Fri, Feb 9, 2024 at 5:27 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:

> Nathan Bossart <nathandbossart@gmail.com> writes:
> > On Fri, Feb 09, 2024 at 08:52:26AM +0100, Mats Kindahl wrote:
> >> The types "int" and "size_t" are treated as s32 and u32 respectively
> since
> >> that seems to be the case for most of the code, even if strictly not
> >> correct (size_t can be an unsigned long int for some architecture).
>
> > Why is it safe to do this?
>
> We do pretty much assume that "int" is "int32".  But I agree that
> assuming anything about the width of size_t is bad.  I think we need
> a separate pg_cmp_size() or pg_cmp_size_t().
>

I added precisely one first, but removed it when I saw that all uses
assumed that it was an int. :)

I'll add it back.

Best wishes,
Mats Kindahl

>
>                         regards, tom lane
>