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Jeff King 69bbbe484b hash-object: use fsck for object checks 
Since c879daa237 (Make hash-object more robust against malformed
objects, 2011-02-05), we've done some rudimentary checks against objects
we're about to write by running them through our usual parsers for
trees, commits, and tags.

These parsers catch some problems, but they are not nearly as careful as
the fsck functions (which make sense; the parsers are designed to be
fast and forgiving, bailing only when the input is unintelligible). We
are better off doing the more thorough fsck checks when writing objects.
Doing so at write time is much better than writing garbage only to find
out later (after building more history atop it!) that fsck complains
about it, or hosts with transfer.fsckObjects reject it.

This is obviously going to be a user-visible behavior change, and the
test changes earlier in this series show the scope of the impact. But
I'd argue that this is OK:

  - the documentation for hash-object is already vague about which
    checks we might do, saying that --literally will allow "any
    garbage[...] which might not otherwise pass standard object parsing
    or git-fsck checks". So we are already covered under the documented
    behavior.

  - users don't generally run hash-object anyway. There are a lot of
    spots in the tests that needed to be updated because creating
    garbage objects is something that Git's tests disproportionately do.

  - it's hard to imagine anyone thinking the new behavior is worse. Any
    object we reject would be a potential problem down the road for the
    user. And if they really want to create garbage, --literally is
    already the escape hatch they need.

Note that the change here is actually in index_mem(), which handles the
HASH_FORMAT_CHECK flag passed by hash-object. That flag is also used by
"git-replace --edit" to sanity-check the result. Covering that with more
thorough checks likewise seems like a good thing.

Besides being more thorough, there are a few other bonuses:

  - we get rid of some questionable stack allocations of object structs.
    These don't seem to currently cause any problems in practice, but
    they subtly violate some of the assumptions made by the rest of the
    code (e.g., the "struct commit" we put on the stack and
    zero-initialize will not have a proper index from
    alloc_comit_index().

  - likewise, those parsed object structs are the source of some small
    memory leaks

  - the resulting messages are much better. For example:

      [before]
      $ echo 'tree 123' | git hash-object -t commit --stdin
      error: bogus commit object 0000000000000000000000000000000000000000
      fatal: corrupt commit

      [after]
      $ echo 'tree 123' | git.compile hash-object -t commit --stdin
      error: object fails fsck: badTreeSha1: invalid 'tree' line format - bad sha1
      fatal: refusing to create malformed object

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-18 12:59:45 -08:00
.github ci: use a newer github-script version 2022-12-10 16:32:16 +09:00
block-sha1
builtin Merge branch 'ab/doc-synopsis-and-cmd-usage' 2022-11-29 10:41:06 +09:00
ci Merge branch 'jx/ci-ubuntu-fix' into maint-2.38 2022-12-10 16:17:47 +09:00
compat Merge branch 'sz/macos-fsmonitor-symlinks' 2022-11-23 11:22:25 +09:00
contrib Merge branch 'ab/fewer-the-index-macros' 2022-12-01 18:38:07 +09:00
Documentation fsck: document the new gitattributes message IDs 2023-01-16 12:03:14 -08:00
ewah
git-gui Makefiles: change search through $(MAKEFLAGS) for GNU make 4.4 2022-12-01 07:24:12 +09:00
gitk-git
gitweb
mergetools
negotiator
oss-fuzz
perl Git.pm: trust rev-parse to find bare repositories 2022-10-22 16:39:48 -07:00
po l10n: zh_TW.po: Git 2.39-rc2 2022-12-11 01:27:25 +08:00
refs
reftable
sha1collisiondetection@855827c583
sha1dc
sha256
t hash-object: use fsck for object checks 2023-01-18 12:59:45 -08:00
templates
trace2
xdiff
.cirrus.yml
.clang-format
.editorconfig
.gitattributes
.gitignore Merge branch 'ab/coccicheck-incremental' 2022-11-23 11:22:23 +09:00
.gitmodules
.mailmap mailmap: update email address of Matheus Tavares 2022-12-10 09:17:36 +09:00
.tsan-suppressions
abspath.c
aclocal.m4
add-interactive.c read-cache API & users: make discard_index() return void 2022-11-21 12:06:15 +09:00
add-interactive.h
add-patch.c read-cache API & users: make discard_index() return void 2022-11-21 12:06:15 +09:00
advice.c
advice.h
alias.c
alias.h
alloc.c alloc.[ch]: remove alloc_report() function 2022-04-01 10:16:11 -07:00
alloc.h
apply.c Merge branch 'tb/cap-patch-at-1gb' 2022-10-30 21:04:43 -04:00
apply.h
archive-tar.c
archive-zip.c
archive.c
archive.h
attr.c attr: adjust a mismatched data type 2023-01-17 06:58:20 -08:00
attr.h Merge branch 'maint-2.35' into maint-2.36 2022-12-13 21:19:11 +09:00
banned.h
base85.c
bisect.c
bisect.h
blame.c
blame.h
blob.c
blob.h
bloom.c
bloom.h
branch.c
branch.h
builtin.h
bulk-checkin.c
bulk-checkin.h
bundle-uri.c
bundle-uri.h
bundle.c
bundle.h Merge branch 'ds/bundle-uri-3' 2022-10-30 21:04:44 -04:00
cache-tree.c
cache-tree.h
cache.h cocci: apply "pending" index-compatibility to some "builtin/*.c" 2022-11-21 12:06:15 +09:00
cbtree.c
cbtree.h
chdir-notify.c
chdir-notify.h
check-builtins.sh
checkout.c
checkout.h
chunk-format.c
chunk-format.h
CODE_OF_CONDUCT.md
color.c
color.h
column.c utf8: fix truncated string lengths in utf8_strnwidth() 2022-12-09 14:26:21 +09:00
column.h
combine-diff.c
command-list.txt
commit-graph.c
commit-graph.h
commit-reach.c
commit-reach.h
commit-slab-decl.h
commit-slab-impl.h
commit-slab.h
commit.c Merge branch 'pw/rebase-keep-base-fixes' 2022-10-30 21:04:42 -04:00
commit.h
common-main.c
config.c Merge branch 'pw/config-int-parse-fixes' 2022-11-28 12:13:43 +09:00
config.h
config.mak.dev
config.mak.in
config.mak.uname
configure.ac
connect.c
connect.h
connected.c receive-pack: only use visible refs for connectivity check 2022-11-17 16:22:52 -05:00
connected.h receive-pack: only use visible refs for connectivity check 2022-11-17 16:22:52 -05:00
convert.c
convert.h
copy.c
COPYING
credential.c
credential.h
csum-file.c
csum-file.h
ctype.c
daemon.c
date.c
date.h
decorate.c
decorate.h
delta-islands.c delta-islands: free island-related data after use 2022-11-18 18:30:49 -05:00
delta-islands.h
delta.h
detect-compiler
diagnose.c
diagnose.h
diff-delta.c
diff-lib.c
diff-merges.c
diff-merges.h
diff-no-index.c
diff.c Merge branch 'sg/plug-line-log-leaks' 2022-11-28 12:13:46 +09:00
diff.h
diffcore-break.c
diffcore-delta.c
diffcore-order.c
diffcore-pickaxe.c
diffcore-rename.c
diffcore-rotate.c
diffcore.h line-log: free diff queue when processing non-merge commits 2022-11-02 20:16:34 -04:00
dir-iterator.c
dir-iterator.h
dir.c
dir.h
editor.c
entry.c
entry.h
environment.c
environment.h
exec-cmd.c
exec-cmd.h
fetch-negotiator.c
fetch-negotiator.h
fetch-pack.c
fetch-pack.h
fmt-merge-msg.c
fmt-merge-msg.h
fsck.c fsck: provide a function to fsck buffer without object struct 2023-01-18 12:59:44 -08:00
fsck.h fsck: provide a function to fsck buffer without object struct 2023-01-18 12:59:44 -08:00
fsmonitor--daemon.h
fsmonitor-ipc.c
fsmonitor-ipc.h
fsmonitor-path-utils.h
fsmonitor-settings.c
fsmonitor-settings.h
fsmonitor.c
fsmonitor.h
generate-cmdlist.sh
generate-configlist.sh
generate-hooklist.sh
gettext.c
gettext.h
git-add--interactive.perl
git-archimport.perl
git-bisect.sh bisect--helper: parse subcommand with OPT_SUBCOMMAND 2022-11-11 17:04:57 -05:00
git-compat-util.h Sync with 2.38.3 2022-12-13 21:25:15 +09:00
git-curl-compat.h
git-cvsexportcommit.perl
git-cvsimport.perl
git-cvsserver.perl
git-difftool--helper.sh
git-filter-branch.sh
git-instaweb.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-quiltimport.sh
git-request-pull.sh
git-send-email.perl
git-sh-i18n.sh
git-sh-setup.sh
git-submodule.sh submodule--helper: drop "update --prefix <pfx>" for "-C <pfx> update" 2022-11-08 14:55:30 -05:00
git-svn.perl
GIT-VERSION-GEN Git 2.39.1 2022-12-13 21:25:28 +09:00
git-web--browse.sh
git.c Merge branch 'ab/submodule-helper-prep-only' 2022-11-23 11:22:22 +09:00
git.rc
gpg-interface.c
gpg-interface.h
graph.c
graph.h
grep.c
grep.h
hash-lookup.c
hash-lookup.h
hash.h
hashmap.c
hashmap.h
help.c
help.h
hex.c
hook.c
hook.h
http-backend.c
http-fetch.c
http-push.c
http-walker.c
http.c http: redact curl h2h3 headers in info 2022-11-14 17:42:46 -05:00
http.h
ident.c
imap-send.c
INSTALL INSTALL: remove discussion of SHA-1 backends 2022-11-07 22:11:51 -05:00
iterator.h
json-writer.c
json-writer.h
khash.h
kwset.c
kwset.h
levenshtein.c
levenshtein.h
LGPL-2.1
line-log.c line-log: free the diff queues' arrays when processing merge commits 2022-11-02 20:16:34 -04:00
line-log.h
line-range.c
line-range.h
linear-assignment.c
linear-assignment.h
list-objects-filter-options.c
list-objects-filter-options.h
list-objects-filter.c list-objects-filter: plug combine_filter_data leak 2022-11-21 16:43:26 +09:00
list-objects-filter.h
list-objects.c
list-objects.h
list.h
ll-merge.c Merge branch 'rs/no-more-run-command-v' 2022-11-08 17:15:12 -05:00
ll-merge.h
lockfile.c
lockfile.h
log-tree.c
log-tree.h
ls-refs.c refs: get rid of global list of hidden refs 2022-11-17 16:22:51 -05:00
ls-refs.h
mailinfo.c
mailinfo.h
mailmap.c
mailmap.h shortlog: remove unused(?) "repo-abbrev" feature 2021-01-12 14:04:42 -08:00
Makefile Merge branch 'ab/coccicheck-incremental' 2022-11-23 11:22:23 +09:00
match-trees.c
mem-pool.c
mem-pool.h
merge-blobs.c
merge-blobs.h
merge-ort-wrappers.c
merge-ort-wrappers.h
merge-ort.c Merge branch 'en/ort-dir-rename-and-symlink-fix' 2022-10-30 21:04:43 -04:00
merge-ort.h
merge-recursive.c merge-recursive: fix variable typo in error message 2022-11-27 10:26:10 +09:00
merge-recursive.h
merge.c
mergesort.h
midx.c
midx.h
name-hash.c
notes-cache.c
notes-cache.h
notes-merge.c
notes-merge.h
notes-utils.c
notes-utils.h
notes.c
notes.h
object-file.c hash-object: use fsck for object checks 2023-01-18 12:59:45 -08:00
object-name.c
object-store.h
object.c parse_object(): simplify blob conditional 2022-11-22 10:13:54 +09:00
object.h
oid-array.c
oid-array.h
oidmap.c
oidmap.h
oidset.c
oidset.h
oidtree.c
oidtree.h
pack-bitmap-write.c
pack-bitmap.c
pack-bitmap.h
pack-check.c
pack-mtimes.c
pack-mtimes.h
pack-objects.c
pack-objects.h
pack-revindex.c
pack-revindex.h
pack-write.c
pack.h
packfile.c
packfile.h
pager.c
parallel-checkout.c
parallel-checkout.h
parse-options-cb.c
parse-options.c
parse-options.h
patch-delta.c
patch-ids.c Merge branch 'jz/patch-id' 2022-10-30 21:04:41 -04:00
patch-ids.h
path.c
path.h
pathspec.c
pathspec.h
pkt-line.c
pkt-line.h
preload-index.c
pretty.c Sync with Git 2.37.5 2022-12-13 21:23:36 +09:00
pretty.h
prio-queue.c
prio-queue.h
progress.c
progress.h
promisor-remote.c
promisor-remote.h
prompt.c
prompt.h
protocol-caps.c
protocol-caps.h
protocol.c
protocol.h
prune-packed.c
prune-packed.h
quote.c
quote.h
range-diff.c
range-diff.h
reachable.c
reachable.h
read-cache.c read-cache API & users: make discard_index() return void 2022-11-21 12:06:15 +09:00
README.md
rebase-interactive.c
rebase-interactive.h
rebase.c
rebase.h
ref-filter.c ref-filter: fix parsing of signatures with CRLF and no body 2022-11-02 21:36:04 -04:00
ref-filter.h
reflog-walk.c
reflog-walk.h
reflog.c
reflog.h
refs.c refs: get rid of global list of hidden refs 2022-11-17 16:22:51 -05:00
refs.h refs: get rid of global list of hidden refs 2022-11-17 16:22:51 -05:00
refspec.c
refspec.h
RelNotes Git 2.39.1 2022-12-13 21:25:28 +09:00
remote-curl.c
remote.c
remote.h
replace-object.c
replace-object.h
repo-settings.c Merge branch 'es/mark-gc-cruft-as-experimental' 2022-11-08 17:14:48 -05:00
repository.c {builtin/*,repository}.c: add & use "USE_THE_INDEX_VARIABLE" 2022-11-21 12:06:15 +09:00
repository.h Merge branch 'es/mark-gc-cruft-as-experimental' 2022-11-08 17:14:48 -05:00
rerere.c
rerere.h
reset.c rebase: use 'skip_cache_tree_update' option 2022-11-10 21:49:34 -05:00
reset.h
resolve-undo.c
resolve-undo.h
revision.c Merge branch 'ps/receive-use-only-advertised' 2022-11-23 11:22:25 +09:00
revision.h Merge branch 'ps/receive-use-only-advertised' 2022-11-23 11:22:25 +09:00
run-command.c Merge branch 'rs/no-more-run-command-v' 2022-11-08 17:15:12 -05:00
run-command.h Merge branch 'rs/no-more-run-command-v' 2022-11-08 17:15:12 -05:00
scalar.c Merge branch 'js/remove-stale-scalar-repos' 2022-11-23 11:22:23 +09:00
SECURITY.md
send-pack.c
send-pack.h
sequencer.c rebase --update-refs: avoid unintended ref deletion 2022-12-09 19:31:45 +09:00
sequencer.h sequencer: stop exporting GIT_REFLOG_ACTION 2022-11-09 18:15:43 -05:00
serve.c
serve.h
server-info.c
setup.c
sh-i18n--envsubst.c
sha1dc_git.c
sha1dc_git.h Makefile & test-tool: replace "DC_SHA1" variable with a "define" 2022-11-07 22:11:51 -05:00
shallow.c
shallow.h
shared.mak Merge branch 'ab/gnumake-4.4-fix' 2022-12-01 18:38:07 +09:00
shell.c
shortlog.h
sideband.c
sideband.h
sigchain.c
sigchain.h
simple-ipc.h
sparse-index.c index: raise a bug if the index is materialised more than once 2022-11-04 20:28:28 -04:00
sparse-index.h
split-index.c
split-index.h
stable-qsort.c
strbuf.c
strbuf.h
streaming.c
streaming.h
string-list.c
string-list.h
strmap.c
strmap.h
strvec.c
strvec.h
sub-process.c
sub-process.h
submodule-config.c
submodule-config.h
submodule.c Merge branch 'jt/submodule-on-demand' 2022-11-23 11:22:25 +09:00
submodule.h submodule API & "absorbgitdirs": remove "----recursive" option 2022-11-08 14:55:30 -05:00
symlinks.c
tag.c
tag.h
tar.h
tempfile.c
tempfile.h
thread-utils.c
thread-utils.h
tmp-objdir.c
tmp-objdir.h
trace2.c
trace2.h
trace.c
trace.h
trailer.c
trailer.h
transport-helper.c
transport-internal.h
transport.c Merge branch 'ds/bundle-uri-3' 2022-10-30 21:04:44 -04:00
transport.h
tree-diff.c
tree-walk.c
tree-walk.h
tree.c
tree.h
unicode-width.h
unimplemented.sh
unix-socket.c
unix-socket.h
unix-stream-server.c
unix-stream-server.h
unpack-trees.c unpack-trees: add 'skip_cache_tree_update' option 2022-11-10 21:49:34 -05:00
unpack-trees.h unpack-trees: add 'skip_cache_tree_update' option 2022-11-10 21:49:34 -05:00
upload-pack.c refs: get rid of global list of hidden refs 2022-11-17 16:22:51 -05:00
upload-pack.h
url.c
url.h
urlmatch.c
urlmatch.h
usage.c
userdiff.c
userdiff.h
utf8.c Sync with Git 2.31.6 2022-12-13 21:09:40 +09:00
utf8.h Sync with Git 2.31.6 2022-12-13 21:09:40 +09:00
varint.c
varint.h
version.c
version.h
versioncmp.c
walker.c
walker.h
wildmatch.c
wildmatch.h
worktree.c
worktree.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

README.md

Build status

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 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 with just "subscribe git" in the body to majordomo@vger.kernel.org (not the Git list). 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