From: Junio C Hamano <gitster@pobox.com>
Date: Thu, 07 May 2020 21:58:16 GMT
Subject: Re: [PATCH v2] ci: allow per-branch config for GitHub Actions
Message-ID: <xmqqo8qz2yrr.fsf@gitster.c.googlers.com>
In-Reply-To: <20200507204626.GG29683@coredump.intra.peff.net>

Jeff King <peff@peff.net> writes:

> It was deliberate in the sense that I would allow them to write useful
> messages to the Actions log. If they want to do nonsense like
> "::set-output", then it's their foot and their gun.

It's not like fooling the framework you laid out here is a
potentially useful attack vector.  We can assume that it is unlikely
for the custom allow-ref to be writing a string that happens to
begin with double-colon by mistake and making it harder to debug.

> I don't know if Actions distinguishes between stdout and stderr here
> (i.e., if we redirected the script's stdout to stderr, would that
> prevent this case or not?).

Perhaps we can experiment with "echo >&2 we are getting called" in
the allow-ref script itself ;-).

In any case, I'll queue it on 'pu'.  Thanks.