From: Stefan Beller <sbeller@google.com>
To: "René Scharfe" <l.s.r@web.de>
Cc: jeremy@feusi.co, git <git@vger.kernel.org>,
Prathamesh Chavan <pc44800@gmail.com>,
Junio C Hamano <gitster@pobox.com>
Subject: Re: Null pointer dereference in git-submodule
Date: Tue, 27 Mar 2018 23:50:44 +0000 [thread overview]
Message-ID: <CAGZ79kYagdvpOcZykF4JPQc9vpVb8_xyFiQkE9yznBQTD1PWJw@mail.gmail.com> (raw)
In-Reply-To: <9c3c0161-f894-3368-ece2-500d0bb6f475@web.de>
On Sun, Mar 25, 2018 at 3:58 AM René Scharfe <l.s.r@web.de> wrote:
> Am 25.03.2018 um 11:50 schrieb Jeremy Feusi:
> >
> > Hmm... That's weird. I can reproduce it on 3 independant systems with
> > versions 2.16.2 up, although it does not work with version 2.11.0.
> > Anyway, I figured out how to reproduce this bug. It is caused when a
> > submodule is added and then the directory it resides in is moved or
> > deleted without commiting. For example:
> >
> > git init
> > git submodule add https://github.com/git/git git
> > mv git git.BAK
> > git submodule status #this command segfaults
> With the patch I sent in my first reply the last command reports:
> fatal: no ref store in submodule 'git'
> That may not be the most helpful message -- not just the ref store is
> missing, the whole submodule is gone!
> Come to think about it, this removal may be intended. How about
> showing the submodule as not being initialized at that point?
At first I thought we could still retrieve the ref store via a lookup of
path -> name in .gitmodules and then navigate to
.git/modules<name>/ (as seen from the superproject)
and load the ref store. But loading the refstore is a mere detail.
"not initialized" is technically correct, the existing git directory
inside the superproject doesn't matter.
> -- >8 --
> Subject: [PATCH v2] submodule: check for NULL return of
get_submodule_ref_store()
Maybe more imperative, telling what we actually want
to achieve instead of what we do?
submodule: report deleted submodules as not initialized
> If we can't find a ref store for a submodule then assume it the latter
> is not initialized (or was removed). Print a status line accordingly
> instead of causing a segmentation fault by passing NULL as the first
> parameter of refs_head_ref().
Thanks for the message here. Looks good!
> Reported-by: Jeremy Feusi <jeremy@feusi.co>
Please also sign off instead of just claiming to report it.
(The sign off has legal implications, see
https://developercertificate.org/ or our copy in
Documentation/SubmittingPatches)
> Signed-off-by: Rene Scharfe <l.s.r@web.de>
> ---
> Test missing..
Which would be added in t/t7400-submodule-basic.sh
Thanks for coming up with a sensible patch!
Stefan
> builtin/submodule--helper.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
> diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
> index ee020d4749..ae3014ac5a 100644
> --- a/builtin/submodule--helper.c
> +++ b/builtin/submodule--helper.c
> @@ -654,9 +654,13 @@ static void status_submodule(const char *path, const
struct object_id *ce_oid,
> displaypath);
> } else if (!(flags & OPT_CACHED)) {
> struct object_id oid;
> + struct ref_store *refs = get_submodule_ref_store(path);
> - if (refs_head_ref(get_submodule_ref_store(path),
> - handle_submodule_head_ref, &oid))
> + if (!refs) {
> + print_status(flags, '-', path, ce_oid,
displaypath);
> + goto cleanup;
> + }
> + if (refs_head_ref(refs, handle_submodule_head_ref, &oid))
> die(_("could not resolve HEAD ref inside the "
> "submodule '%s'"), path);
> --
> 2.17.0.rc1.38.g7c51fd80b8
next prev parent reply other threads:[~2018-03-27 23:50 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-25 9:50 Null pointer dereference in git-submodule Jeremy Feusi
2018-03-25 10:57 ` René Scharfe
2018-03-27 23:50 ` Stefan Beller [this message]
2018-03-28 16:52 ` Junio C Hamano
2018-03-28 17:03 ` Stefan Beller
2018-03-28 18:38 ` [PATCH] submodule: check for NULL return of get_submodule_ref_store() Stefan Beller
2018-03-28 18:57 ` Eric Sunshine
2018-03-28 20:08 ` Stefan Beller
2018-03-28 20:21 ` Eric Sunshine
2018-03-28 20:54 ` Stefan Beller
2018-03-28 21:14 ` René Scharfe
2018-03-28 21:37 ` Stefan Beller
2018-03-28 22:24 ` René Scharfe
2018-03-28 22:35 ` Junio C Hamano
-- strict thread matches above, loose matches on Subject: below --
2018-03-24 17:42 Null pointer dereference in git-submodule Jeremy Feusi
2018-03-24 20:42 ` René Scharfe
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=CAGZ79kYagdvpOcZykF4JPQc9vpVb8_xyFiQkE9yznBQTD1PWJw@mail.gmail.com \
--to=sbeller@google.com \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=jeremy@feusi.co \
--cc=l.s.r@web.de \
--cc=pc44800@gmail.com \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public 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).