git@vger.kernel.org list mirror (unofficial, one of many)
 help / color / mirror / Atom feed
From: "brian m. carlson" <sandals@crustytoothpaste.net>
To: Jeff King <peff@peff.net>
Cc: git@vger.kernel.org
Subject: Re: [PATCH 0/3] --end-of-options marker
Date: Wed, 7 Aug 2019 04:17:49 +0000
Message-ID: <20190807041749.GI118825@genre.crustytoothpaste.net> (raw)
In-Reply-To: <20190806234319.GA19178@sigill.intra.peff.net>

[-- Attachment #1: Type: text/plain, Size: 2321 bytes --]

On 2019-08-06 at 23:43:20, Jeff King wrote:
> On Tue, Aug 06, 2019 at 10:58:53PM +0000, brian m. carlson wrote:
> > Sorry, I hadn't had a chance to look at this series in depth, but I was
> > wondering: could we not just accept two separate "--" arguments, and if
> > there are two of them, interpret the first with the traditional meaning
> > and the second with the Git-specific meaning? That would be much more
> > intuitive for folks, although I suspect it would take a little more work
> > in the options parser.
> 
> That also crossed my mind, but I think it opens up some complicated
> corner cases.  For instance, if I'm parsing left-to-right and see "--",
> how do I know which separator it is meant to be? I think the only rule
> that makes sense is that you must have two "--", like:
> 
>   git rev-list [options] -- [revs] -- [paths]

I was assuming that we wouldn't have a huge number of command-line
arguments and we'd check ahead, although that could of course cause some
pain when used with xargs, I suppose, especially on Linux with its huge
ARG_MAX.

> but that means parsing the whole thing before we can interpret any of
> it. What kinds of tricks can an attacker play by putting "--" in the
> revs or paths areas? E.g., what does this mean:
> 
>   # expanded from "git rev-list -- $revs -- $paths"
>   git rev-list -- --foo -- -- --bar --
> 
> I think if we at least choose the left-most "--" as the official
> end-of-options then they can't inject an option (they can only inject a
> rev as a path). I guess that's the same as with --end-of-options. But it
> somehow feels less clear to me than a separate marker.

I suppose if there's more than two, then interpret the first one as the
end-of-options marker, the second one in the traditional way, and any
subsequent ones as pathspecs matching the file "--". Writing such a
command line would be silly, but we'd fail secure.

> It also doesn't allow this:
> 
>   # allow paths and revs, with optional separator, but no more options
>   git rev-list --end-of-options "$@"
> 
> though I'm not sure whether anybody cares.

That's a good point. I don't have a strong view either way, but I
thought I'd ask about alternatives.
-- 
brian m. carlson: Houston, Texas, US
OpenPGP: https://keybase.io/bk2204

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 868 bytes --]

  reply	other threads:[~2019-08-07  4:17 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-06 14:38 Jeff King
2019-08-06 14:39 ` [PATCH 1/3] revision: allow --end-of-options to end option parsing Jeff King
2019-08-06 14:40 ` [PATCH 2/3] parse-options: allow --end-of-options as a synonym for "--" Jeff King
2019-08-06 14:40 ` [PATCH 3/3] gitcli: document --end-of-options Jeff King
2019-08-06 16:24 ` [PATCH 0/3] --end-of-options marker Junio C Hamano
2019-08-06 16:36   ` Randall S. Becker
2019-08-06 17:38     ` Jeff King
2019-08-06 17:58       ` Randall S. Becker
2019-08-06 18:14       ` SZEDER Gábor
2019-08-08 10:03         ` Jeff King
2019-08-06 17:33   ` Jeff King
2019-08-06 22:58 ` brian m. carlson
2019-08-06 23:43   ` Jeff King
2019-08-07  4:17     ` brian m. carlson [this message]
2019-08-07 16:54       ` Taylor Blau
2019-08-08 10:28       ` Jeff King

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

  List information: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190807041749.GI118825@genre.crustytoothpaste.net \
    --to=sandals@crustytoothpaste.net \
    --cc=git@vger.kernel.org \
    --cc=peff@peff.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

git@vger.kernel.org list mirror (unofficial, one of many)

This inbox may be cloned and mirrored by anyone:

	git clone --mirror https://public-inbox.org/git
	git clone --mirror http://ou63pmih66umazou.onion/git
	git clone --mirror http://czquwvybam4bgbro.onion/git
	git clone --mirror http://hjrcffqmbrq6wope.onion/git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V1 git git/ https://public-inbox.org/git \
		git@vger.kernel.org
	public-inbox-index git

Example config snippet for mirrors.
Newsgroups are available over NNTP:
	nntp://news.public-inbox.org/inbox.comp.version-control.git
	nntp://ou63pmih66umazou.onion/inbox.comp.version-control.git
	nntp://czquwvybam4bgbro.onion/inbox.comp.version-control.git
	nntp://hjrcffqmbrq6wope.onion/inbox.comp.version-control.git
	nntp://news.gmane.io/gmane.comp.version-control.git
 note: .onion URLs require Tor: https://www.torproject.org/

code repositories for the project(s) associated with this inbox:

	https://80x24.org/mirrors/git.git

AGPL code for this site: git clone https://public-inbox.org/public-inbox.git