From: Tom Lane <tgl@sss.pgh.pa.us>
To: =?utf-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?= <ilmari@ilmari.org>
cc: Nathan Bossart <nathandbossart@gmail.com>,
        Kyotaro Horiguchi <horikyota.ntt@gmail.com>, michael@paquier.xyz,
        gurjeet@singh.im, pgsql-hackers@postgresql.org
Subject: Re: Unprivileged user can induce crash by using an SUSET param in
 PGOPTIONS
In-reply-to: <87edy7j1zz.fsf@wibble.ilmari.org>
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 <20220722.151600.1094104349120879204.horikyota.ntt@gmail.com>
 <729330.1658516182@sss.pgh.pa.us> <20220722223359.GB3998906@nathanxps13>
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 <954936.1658597004@sss.pgh.pa.us> <20220725034040.GA4085281@nathanxps13>
 <1834276.1658720963@sss.pgh.pa.us> <20220725043044.GC4085281@nathanxps13>
 <2015981.1658759562@sss.pgh.pa.us> <87ilnli57b.fsf@wibble.ilmari.org>
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Comments: In-reply-to =?utf-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?=
 <ilmari@ilmari.org>
	message dated "Tue, 26 Jul 2022 17:02:40 +0100"
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Date: Tue, 26 Jul 2022 12:04:33 -0400
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=?utf-8?Q?Dagfinn_Ilmari_Manns=C3=A5ker?= <ilmari@ilmari.org> writes:
> Thanks!  Just one minor nitpick: setting an %ENV entry to `undef`
> doesn't unset the environment variable, it sets it to the empty string.
> To unset a variable it needs to be deleted from %ENV, i.e. `delete
> $ENV{PGUSER};`.

Ah.  Still, libpq doesn't distinguish, so the test works anyway.
Not sure if it's worth changing.

			regards, tom lane