When cloning directly from a local repository, we load a list of refs
based on scanning the $GIT_DIR/refs/ directory of the "server"
repository. If files exist in that directory that do not parse as
hexadecimal hashes, then the ref array used by write_remote_refs()
ends up with some entries with null OIDs. This causes us to hit a BUG()
statement in ref_transaction_create():
BUG: create called without valid new_oid
This BUG() call used to be a die() until 033abf97f (Replace all
die("BUG: ...") calls by BUG() ones, 2018-05-02). Before that, the die()
was added by f04c5b552 (ref_transaction_create(): check that new_sha1 is
valid, 2015-02-17).
The original report for this bug [1] mentioned that this problem did not
exist in Git 2.27.0. The failure bisects unsurprisingly to 968f12fda
(refs: turn on GIT_REF_PARANOIA by default, 2021-09-24). When
GIT_REF_PARANOIA is enabled, this case always fails as far back as I am
able to successfully compile and test the Git codebase.
[1] https://github.com/git-for-windows/git/issues/3781
There are two approaches to consider here. One would be to remove this
BUG() statement in favor of returning with an error. There are only two
callers to ref_transaction_create(), so this would have a limited
impact.
The other approach would be to add special casing in 'git clone' to
avoid this faulty input to the method.
While I originally started with changing 'git clone', I decided that
modifying ref_transaction_create() was a more complete solution. This
prevents failing with a BUG() statement when we already have a good way
to report an error (including a reason for that error) within the
method. Both callers properly check the return value and die() with the
error message, so this is an appropriate direction.
The added test helps check against a regression, but does check that our
intended error message is handled correctly.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an
unusually rich command set that provides both high-level operations
and full access to internals.
Git is an Open Source project covered by the GNU General Public
License version 2 (some parts of it are under different licenses,
compatible with the GPLv2). It was originally written by Linus
Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/
including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
Issues which are security relevant should be disclosed privately to
the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that
list the current status of various development topics to the mailing
list. The discussion following them give a good reference for
project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very
first version. He described the tool as "the stupid content tracker"
and the name as (depending on your mood):
random three-letter combination that is pronounceable, and not
actually used by any common UNIX command. The fact that it is a
mispronunciation of "get" may or may not be relevant.
stupid. contemptible and despicable. simple. Take your pick from the
dictionary of slang.
"global information tracker": you're in a good mood, and it actually
works for you. Angels sing, and a light suddenly fills the room.
"goddamn idiotic truckload of sh*t": when it breaks
