f53c5de29c
'git {log,diff,...} -S<...> --pickaxe-regex' can segfault as a result
of out-of-bounds memory reads.
diffcore-pickaxe.c:contains() looks for all matches of the given regex
in a buffer in a loop, advancing the buffer pointer to the end of the
last match in each iteration. When we switched to REG_STARTEND in
b7d36ffca (regex: use regexec_buf(), 2016-09-21), we started passing
the size of that buffer to the regexp engine, too. Unfortunately,
this buffer size is never updated on subsequent iterations, and as the
buffer pointer advances on each iteration, this "bufptr+bufsize"
points past the end of the buffer. This results in segmentation
fault, if that memory can't be accessed. In case of 'git log' it can
also result in erroneously listed commits, if the memory past the end
of buffer is accessible and happens to contain data matching the
regex.
Reduce the buffer size on each iteration as the buffer pointer is
advanced, thus maintaining the correct end of buffer location.
Furthermore, make sure that the buffer pointer is not dereferenced in
the control flow statements when we already reached the end of the
buffer.
The new test is flaky, I've never seen it fail on my Linux box even
without the fix, but this is expected according to db5dfa3 (regex:
-G<pattern> feeds a non NUL-terminated string to regexec() and fails,
2016-09-21). However, it did fail on Travis CI with the first (and
incomplete) version of the fix, and based on that commit message I
would expect the new test without the fix to fail most of the time on
Windows.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.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 http://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 http://news.gmane.org/gmane.comp.version-control.git/, http://marc.info/?l=git and other archival sites.
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