8d133f500a
To keep track of which object filters are allowed or not, 'git
upload-pack' stores the name of each filter in a string_list, and sets
it ->util pointer to be either 0 or 1, indicating whether it is banned
or allowed.
Later on, we attempt to clear that list, but we incorrectly ask for the
util pointers to be free()'d, too. This behavior (introduced back in
6dd3456a8c (upload-pack.c: allow banning certain object filter(s),
2020-08-03)) leads to an invalid free, and causes us to crash.
In order to trigger this, one needs to fetch from a server that (a) has
at least one object filter allowed, and (b) issue a fetch that contains
a subset of the allowed filters (i.e., we cannot ask for a banned
filter, since this causes us to die() before we hit the bogus
string_list_clear()).
In that case, whatever banned filters exist will cause a noop free()
(since those ->util pointers are set to 0), but the first allowed filter
we try to free will crash us.
We never noticed this in the tests because we didn't have an example of
setting 'uploadPackFilter' configuration variables and then following up
with a valid fetch. The first new 'git clone' prevents further
regression here. For good measure on top, add a test which checks the
same behavior at a tree depth greater than 0.
Signed-off-by: Taylor Blau <me@ttaylorr.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).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just "subscribe git" in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.
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