Date: Tue, 19 Jul 2022 14:41:42 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Michael Paquier <michael@paquier.xyz>, pgsql-hackers@postgresql.org
Subject: Re: pg_parameter_aclcheck() and trusted extensions
Message-ID: <20220719214142.GA3720087@nathanxps13>
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On Tue, Jul 19, 2022 at 04:27:08PM -0400, Tom Lane wrote:
> Nathan Bossart <nathandbossart@gmail.com> writes:
>> However, I wonder if a
>> better way to fix this is to provide a way to stop set_config_option() from
>> throwing errors (e.g., setting elevel to -1).  That way, we could remove
>> the manual permissions checks in favor of always using the real ones, which
>> might help prevent similar bugs in the future.
> 
> I thought about that for a bit.  You could almost do it today if you
> passed elevel == DEBUG5; the ensuing log chatter for failures would be
> down in the noise compared to everything else you would see with
> min_messages cranked down that far.  However,
> 
> (1) As things stand, set_config_option()'s result does not distinguish
> no-permissions failures from other problems, so we'd need some rejiggering
> of its API anyway.
> 
> (2) As you mused upthread, it's possible that ACL_SET isn't what we should
> be checking here, but some more-specific privilege.  So I'd just as soon
> keep this privilege check separate from set_config_option's.

I think we'd also need to keep the manual permissions checks for
placeholders, so it wouldn't save much, anyway.

> I'll push ahead with fixing it like this.

Sounds good.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com