From: Jeff King <peff@peff.net>
Date: Sat, 18 Oct 2025 09:51:25 GMT
Subject: Re: t7528-signed-commit-ssh.sh fails due to ssh-agent fails to start with ENAMETOOLONG
Message-ID: <20251018095125.GE1060824@coredump.intra.peff.net>
In-Reply-To: <xmqqbjm51l3a.fsf@gitster.g>

On Fri, Oct 17, 2025 at 10:42:17AM -0700, Junio C Hamano wrote:

> Jeff King <peff@peff.net> writes:
> 
> > AFAICT, ssh-agent does not quote the path in its output. So for example:
> >
> >   d='/tmp/has spaces'
> >   mkdir "$d"
> >   HOME=$d ssh-agent
> >
> > will produce:
> >
> >   SSH_AUTH_SOCK=/tmp/has spaces/.ssh/agent/s.IcPuGe26YY.agent.6PtD3uhM4O; export SSH_AUTH_SOCK;
> >
> > which is nonsense to eval.
> 
> So if $d were
> 
>     d='/tmp/has rm -rf in it'
> 
> would that produce some interesting side effect?

Yep. Somewhat terrifying, though I guess if an attacker controls your
$HOME environment variable you probably have bigger worries.

-Peff