2455720950
It is possible to trigger an integer overflow when parsing attribute
names that are longer than 2^31 bytes because we assign the result of
strlen(3P) to an `int` instead of to a `size_t`. This can lead to an
abort in vsnprintf(3P) with the following reproducer:
blob=$(perl -e 'print "A " . "B"x2147483648 . "\n"' | git hash-object -w --stdin)
git update-index --add --cacheinfo 100644,$blob,.gitattributes
git check-attr --all path
BUG: strbuf.c:400: your vsnprintf is broken (returned -1)
But furthermore, assuming that the attribute name is even longer than
that, it can cause us to silently truncate the attribute and thus lead
to wrong results.
Fix this integer overflow by using a `size_t` instead. This fixes the
silent truncation of attribute names, but it only partially fixes the
BUG we hit: even though the initial BUG is fixed, we can still hit a BUG
when parsing invalid attribute lines via `report_invalid_attr()`.
This is due to an underlying design issue in vsnprintf(3P) which only
knows to return an `int`, and thus it may always overflow with large
inputs. This issue is benign though: the worst that can happen is that
the error message is misreported to be either truncated or too long, but
due to the buffer being NUL terminated we wouldn't ever do an
out-of-bounds read here.
Reported-by: Markus Vervier <markus.vervier@x41-dsec.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
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).
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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