1
0
mirror of https://github.com/git/git.git synced 2024-09-21 09:42:22 +02:00
Git Source Code Mirror. Please follow Documentation/SubmittingPatches procedure for any of your improvements.
Go to file
Jeff King 3b910d0c5e add tests for indexing packs with delta cycles
If we receive a broken or malicious pack from a remote, we
will feed it to index-pack. As index-pack processes the
objects as a stream, reconstructing and hashing each object
to get its name, it is not very susceptible to doing the
wrong with bad data (it simply notices that the data is
bogus and aborts).

However, one question raised on the list is whether it could
be susceptible to problems during the delta-resolution
phase. In particular, can a cycle in the packfile deltas
cause us to go into an infinite loop or cause any other
problem?

The answer is no.

We cannot have a cycle of delta-base offsets, because they
go only in one direction (the OFS_DELTA object mentions its
base by an offset towards the beginning of the file, and we
explicitly reject negative offsets).

We can have a cycle of REF_DELTA objects, which refer to
base objects by sha1 name. However, index-pack does not know
these sha1 names ahead of time; it has to reconstruct the
objects to get their names, and it cannot do so if there is
a delta cycle (in other words, it does not even realize
there is a cycle, but only that there are items that cannot
be resolved).

Even though we can reason out that index-pack should handle
this fine, let's add a few tests to make sure it behaves
correctly.

Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-08-24 22:31:47 -07:00
block-sha1
builtin
compat
contrib
Documentation
git_remote_helpers
git-gui
gitk-git
gitweb
mergetools
perl
po
ppc
t add tests for indexing packs with delta cycles 2013-08-24 22:31:47 -07:00
templates
vcs-svn
xdiff
.gitattributes
.gitignore
.mailmap
abspath.c
aclocal.m4
advice.c
advice.h
alias.c
alloc.c
archive-tar.c
archive-zip.c
archive.c
archive.h
argv-array.c
argv-array.h
attr.c
attr.h
base85.c
bisect.c
bisect.h
blob.c
blob.h
branch.c
branch.h
builtin.h
bulk-checkin.c
bulk-checkin.h
bundle.c
bundle.h
cache-tree.c
cache-tree.h
cache.h
check_bindir
check-builtins.sh
check-racy.c
color.c
color.h
column.c
column.h
combine-diff.c
command-list.txt
commit.c
commit.h
config.c
config.mak.in
config.mak.uname
configure.ac
connect.c
connected.c
connected.h
convert.c
convert.h
copy.c
COPYING
credential-cache--daemon.c
credential-cache.c
credential-store.c
credential.c
credential.h
csum-file.c
csum-file.h
ctype.c
daemon.c
date.c
decorate.c
decorate.h
delta.h
diff-delta.c
diff-lib.c
diff-no-index.c
diff.c
diff.h
diffcore-break.c
diffcore-delta.c
diffcore-order.c
diffcore-pickaxe.c
diffcore-rename.c
diffcore.h
dir.c
dir.h
editor.c
entry.c
environment.c
exec_cmd.c
exec_cmd.h
fast-import.c
fetch-pack.c
fetch-pack.h
fmt-merge-msg.h
fsck.c
fsck.h
generate-cmdlist.sh
gettext.c
gettext.h
git-add--interactive.perl
git-am.sh
git-archimport.perl
git-bisect.sh
git-compat-util.h
git-cvsexportcommit.perl
git-cvsimport.perl
git-cvsserver.perl
git-difftool--helper.sh
git-difftool.perl
git-filter-branch.sh
git-instaweb.sh
git-lost-found.sh
git-merge-octopus.sh
git-merge-one-file.sh
git-merge-resolve.sh
git-mergetool--lib.sh
git-mergetool.sh
git-p4.py
git-parse-remote.sh
git-pull.sh
git-quiltimport.sh
git-rebase--am.sh
git-rebase--interactive.sh
git-rebase--merge.sh
git-rebase.sh
git-relink.perl
git-remote-testgit
git-remote-testpy.py
git-repack.sh
git-request-pull.sh
git-send-email.perl
git-sh-i18n.sh
git-sh-setup.sh
git-stash.sh
git-submodule.sh
git-svn.perl
GIT-VERSION-GEN
git-web--browse.sh
git.c
git.spec.in
gpg-interface.c
gpg-interface.h
graph.c
graph.h
grep.c
grep.h
hash.c
hash.h
help.c
help.h
hex.c
http-backend.c
http-fetch.c
http-push.c
http-walker.c
http.c
http.h
ident.c
imap-send.c
INSTALL
kwset.c
kwset.h
levenshtein.c
levenshtein.h
LGPL-2.1
list-objects.c
list-objects.h
ll-merge.c
ll-merge.h
lockfile.c
log-tree.c
log-tree.h
mailmap.c
mailmap.h
Makefile
match-trees.c
merge-blobs.c
merge-blobs.h
merge-recursive.c
merge-recursive.h
merge.c
mergesort.c
mergesort.h
name-hash.c
notes-cache.c
notes-cache.h
notes-merge.c
notes-merge.h
notes.c
notes.h
object.c
object.h
pack-check.c
pack-refs.c
pack-refs.h
pack-revindex.c
pack-revindex.h
pack-write.c
pack.h
pager.c
parse-options-cb.c
parse-options.c
parse-options.h
patch-delta.c
patch-ids.c
patch-ids.h
path.c
pathspec.c
pathspec.h
pkt-line.c
pkt-line.h
preload-index.c
pretty.c
progress.c
progress.h
prompt.c
prompt.h
quote.c
quote.h
reachable.c
reachable.h
read-cache.c
README
reflog-walk.c
reflog-walk.h
refs.c
refs.h
RelNotes
remote-curl.c
remote-testsvn.c
remote.c
remote.h
replace_object.c
rerere.c
rerere.h
resolve-undo.c
resolve-undo.h
revision.c
revision.h
run-command.c
run-command.h
send-pack.c
send-pack.h
sequencer.c
sequencer.h
server-info.c
setup.c
sh-i18n--envsubst.c
sha1_file.c
sha1_name.c
sha1-array.c
sha1-array.h
sha1-lookup.c
sha1-lookup.h
shallow.c
shell.c
shortlog.h
show-index.c
sideband.c
sideband.h
sigchain.c
sigchain.h
strbuf.c
strbuf.h
streaming.c
streaming.h
string-list.c
string-list.h
submodule.c
submodule.h
symlinks.c
tag.c
tag.h
tar.h
test-chmtime.c
test-ctype.c
test-date.c
test-delta.c
test-dump-cache-tree.c
test-genrandom.c
test-index-version.c
test-line-buffer.c
test-match-trees.c
test-mergesort.c
test-mktemp.c
test-parse-options.c
test-path-utils.c
test-read-cache.c
test-regex.c
test-revision-walking.c
test-run-command.c
test-scrap-cache-tree.c
test-sha1.c
test-sha1.sh
test-sigchain.c
test-string-list.c
test-subprocess.c
test-svn-fe.c
test-wildmatch.c
thread-utils.c
thread-utils.h
trace.c
transport-helper.c
transport.c
transport.h
tree-diff.c
tree-walk.c
tree-walk.h
tree.c
tree.h
unimplemented.sh
unix-socket.c
unix-socket.h
unpack-trees.c
unpack-trees.h
upload-pack.c
url.c
url.h
usage.c
userdiff.c
userdiff.h
utf8.c
utf8.h
varint.c
varint.h
version.c
version.h
walker.c
walker.h
wildmatch.c
wildmatch.h
wrap-for-bin.sh
wrapper.c
write_or_die.c
ws.c
wt-status.c
wt-status.h
xdiff-interface.c
xdiff-interface.h
zlib.c

////////////////////////////////////////////////////////////////

	Git - the stupid content tracker

////////////////////////////////////////////////////////////////

"git" can mean anything, 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

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.

See Documentation/gittutorial.txt to get started, then see
Documentation/everyday.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).

Many Git online resources are accessible from http://git-scm.com/
including full documentation and Git related tools.

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.