From: Jeff King <peff@peff.net>
Date: Mon, 23 Aug 2010 20:33:04 GMT
Subject: Re: "git -c web.browser=w3m help -w help" still kicks firefox
Message-ID: <20100823203304.GB4458@coredump.intra.peff.net>
In-Reply-To: <AANLkTi=R6ZdD9GUO6T6uCUkF+KVPbG1FGrieOfeusKct@mail.gmail.com>

On Mon, Aug 23, 2010 at 09:02:36PM +0200, Alex Riesen wrote:

> Maybe it is worth fixing, but on a case-by-case basis?
> 
> I mean changing the execv_git_cmd interface (or create a new execv
> function), so that it can get the list of config vars to pass down to
> the callee. A trivial case of its use would be to just pass the
> current config (or, more likely, none).  Or, one could give it its own
> list of config parameters.

I don't think that is enough. We don't necessarily know which config
options will be relevant to exec'd processes. We could be running some
user-defined command that calls a bunch of other git commands. Or a
hook, for that matter.

Which does bring up one interesting boundary. If I run:

  git -c receive.denyDeletes=false git push

what should happen? Obviously with cross-server communication the
environment won't get passed. I am inclined to say that even for local
cases, receive-pack should clear the string. Certainly for the sake of
consistency between local and remote transports, but it may also be a
security issue (in most cases, no, since you would have to be exec'ing
receive-pack directly, and you are clearly already running an arbitrary
command, but I can see somebody perhaps crossing a setuid boundary with
receive-pack).

-Peff