mirror of
https://github.com/git-for-windows/git.git
synced 2026-06-11 08:30:32 -05:00
65ea197dca
Running t4205 under UBSan with the EXPENSIVE prereq enabled triggers an
error when we try to create a commit message that is over 2GB:
commit.c:1574:6: runtime error: signed integer overflow:
-2147483648 - 1 cannot be represented in type 'int'
The problem is that find_invalid_utf8() is not prepared to handle
large buffers, as it uses an "int" to represent buffer sizes and
offsets.
We can fix this with a few changes:
1. We'll take in "len" as a size_t (which is what the caller has
anyway, since it's working with a strbuf).
2. We need to return a size_t to give the offset to the invalid utf8,
but we also need a sentinel value for "no invalid value"
(previously "-1"). Let's split these to return a bool for "found
invalid utf8" and then pass back the offset as an out-parameter.
We'll switch the function name to match the new semantics.
3. The caller in verify_utf8() uses a "long" to store buffer
positions, which is a bit funny. This goes back to 08a94a145c
(commit/commit-tree: correct latin1 to utf-8, 2012-06-28) and is
perhaps trying to match our use of "unsigned long" for object sizes
(though we don't care about it ever becoming negative here). This
should be a size_t, too, as some platforms (like Windows) still use
a 32-bit long on machines with 64-bit pointers.
4. The "bytes" field within find_invalid_utf() does not have range
problems. It is the number of bytes the utf8 sequence claims to
have, so is limited by how many bits can be set in a single 8-bit
byte. However, if we leave it as an "int" then the compiler will
complain about the sign mismatch when comparing it to "len". So
let's make it unsigned, too.
All of this is a little silly, of course, because 2GB text commit
messages are clearly nonsense. So we might consider rejecting them
outright, but it is easy enough to make these helper functions more
robust in the meantime.
Signed-off-by: Jeff King <peff@peff.net>
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.adoc to get started, then see
Documentation/giteveryday.adoc for a useful minimum set of commands, and
Documentation/git-<commandname>.adoc 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.adoc
(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 and Documentation/CodingGuidelines).
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).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://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