From: Jeff King <email@example.com> To: Brandon Williams <firstname.lastname@example.org> Cc: email@example.com Subject: Re: [PATCH 2/2] submodule: munge paths to submodule git directories Date: Tue, 14 Aug 2018 14:58:00 -0400 [thread overview] Message-ID: <20180814185759.GA28452@sigill.intra.peff.net> (raw) In-Reply-To: <20180814180406.GA86804@google.com> On Tue, Aug 14, 2018 at 11:04:06AM -0700, Brandon Williams wrote: > > I think this backwards-compatibility is necessary to avoid pain. But > > until it goes away, I don't think this is helping the vulnerability from > > 0383bbb901. Because there the issue was that the submodule name pointed > > back into the working tree, so this access() would find the untrusted > > working tree code and say "ah, an old-fashioned name!". > [...] > > Oh I know that this doesn't help with that vulnerability. As you've > said we fix it and now disallow ".." at the submodule-config level so > really this path is simply about using what we get out of > submodule-config in a more sane manor. OK, I'm alright with that as long as we are all on the same page. I think I mistook "this addresses the vulnerability" from your commit message the wrong way. I took it as "this patch", but reading it again, you simply mean "the '..' handling we already did". I do think eventually dropping this back-compatibility could save us from another directory-escape problem, but it's hard to justify the real-world pain for a hypothetical benefit. Maybe in a few years we could get rid of it in a major version bump. > > One interesting thing about url-encoding is that it's not one-to-one. > > This case could also be %2F, which is a different file (on a > > case-sensitive filesystem). I think "%20" and "+" are similarly > > interchangeable. > > > > If we were decoding the filenames, that's fine. The round-trip is > > lossless. > > > > But that's not quite how the new code behaves. We encode the input and > > then check to see if it matches an encoding we previously performed. So > > if our urlencode routines ever change, this will subtly break. > > > > I don't know how much it's worth caring about. We're not that likely to > > change the routines ourself (though certainly a third-party > > implementation would need to know our exact url-encoding decisions). > > This is exactly the reason why I wanted to get some opinions on what the > best thing to do here would be. I _think_ the best thing would probably > be to write a specific routine to do the conversion, and it wouldn't > even have to be all that complex. Basically I'm just interested in > converting '/' characters so that things no longer behave like > nested directories. I think we benefit from catching names that would trigger filesystem case-folding, too. If I have submodules with names "foo" and "FOO", we would not want to confuse them (or at least we should confuse them equally on all platforms). I doubt you can do anything malicious, but it might simply be annoying. That implies to me using a custom function (even if its encoded form ends up being understandable as url-encoding). -Peff
next prev parent reply other threads:[~2018-08-14 18:58 UTC|newest] Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-08-07 23:06 [RFC] " Brandon Williams 2018-08-07 23:25 ` Jonathan Nieder 2018-08-08 0:14 ` Junio C Hamano 2018-08-08 22:33 ` [PATCH 0/2] munge submodule names Brandon Williams 2018-08-08 22:33 ` [PATCH 1/2] submodule: create helper to build paths to submodule gitdirs Brandon Williams 2018-08-08 23:21 ` Stefan Beller 2018-08-09 0:45 ` Brandon Williams 2018-08-10 21:27 ` Junio C Hamano 2018-08-10 21:45 ` Brandon Williams 2018-08-08 22:33 ` [PATCH 2/2] submodule: munge paths to submodule git directories Brandon Williams 2018-08-09 21:26 ` Jeff King 2018-08-14 18:04 ` Brandon Williams 2018-08-14 18:57 ` Jonathan Nieder 2018-08-14 21:08 ` Stefan Beller 2018-08-14 21:12 ` Jonathan Nieder 2018-08-14 22:34 ` Stefan Beller 2018-08-16 2:34 ` Jonathan Nieder 2018-08-16 2:39 ` Stefan Beller 2018-08-16 2:47 ` Jonathan Nieder 2018-08-16 17:34 ` Brandon Williams 2018-08-16 18:19 ` [PATCH] submodule: add config for where gitdirs are located Brandon Williams 2018-08-20 22:03 ` Junio C Hamano 2018-08-16 15:07 ` [PATCH 2/2] submodule: munge paths to submodule git directories Junio C Hamano 2018-08-14 18:58 ` Jeff King [this message] 2018-08-28 21:35 ` Stefan Beller 2018-08-29 5:25 ` Jeff King 2018-08-29 18:10 ` Stefan Beller 2018-08-29 21:03 ` Jeff King 2018-08-29 21:10 ` Stefan Beller 2018-08-29 21:18 ` Jonathan Nieder 2018-08-29 21:27 ` Stefan Beller 2018-08-29 21:30 ` Jeff King 2018-08-29 21:09 ` Jonathan Nieder 2018-08-29 21:14 ` Stefan Beller 2018-08-29 21:25 ` Brandon Williams 2018-08-29 21:32 ` Jeff King 2018-08-16 0:19 ` Aaron Schrab 2019-01-15 1:25 ` [RFC] " Jonathan Nieder 2019-01-17 17:32 ` Jeff King 2019-01-17 17:57 ` Stefan Beller
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=20180814185759.GA28452@sigill.intra.peff.net \ --firstname.lastname@example.org \ --email@example.com \ --firstname.lastname@example.org \ --subject='Re: [PATCH 2/2] submodule: munge paths to submodule git directories' \ /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
Code repositories for project(s) associated with this inbox: https://80x24.org/mirrors/git.git This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).