Commit Graph

69453 Commits

Author SHA1 Message Date
Elijah Newren
b8ad365640 rebase: fix docs about incompatibilities with --root
In commit 5dacd4abdd ("git-rebase.txt: document incompatible options",
2018-06-25), I added notes about incompatibilities between options for
the apply and merge backends.  Unfortunately, I inverted the condition
when --root was incompatible with the apply backend.  Fix the
documentation, and add a testcase that verifies the documentation
matches the code.

While at it, the documentation for --root also tried to cover some of
the backend differences between the apply and merge backends in relation
to reapplying cherry picks.  The information:
  * assumed that the apply backend was the default (it isn't anymore)
  * was written before --reapply-cherry-picks became an option
  * was written before the detailed information on backend differences
All of these factors make the sentence under --root about reapplying
cherry picks contradict information that is now available elsewhere in
the manual, and the other references are correct.  So just strike this
sentence.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-25 09:20:53 -08:00
Elijah Newren
1a66d8c6f6 rebase: remove --allow-empty-message from incompatible opts
--allow-empty-message was turned into a no-op and even documented
as such; the flag is simply ignored.  Since the flag is ignored, it
shouldn't be documented as being incompatible with other flags.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-25 09:20:52 -08:00
Elijah Newren
7d718c552b rebase: flag --apply and --merge as incompatible
Previously, we flagged options which implied --apply as being
incompatible with options which implied --merge.  But if both options
were given explicitly, then we didn't flag the incompatibility.  The
same is true with --apply and --interactive.  Add the check, and add
some testcases to verify these are also caught.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-25 09:20:52 -08:00
Elijah Newren
1207599e83 rebase: mark --update-refs as requiring the merge backend
--update-refs is built in terms of the sequencer, which requires the
merge backend.  It was already marked as incompatible with the apply
backend in the git-rebase manual, but the code didn't check for this
incompatibility and warn the user.  Check and error now.

While at it, fix a typo in t3422...and fix some misleading wording
(most options which used to be am-specific have since been implemented
in the merge backend as well).

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-25 09:20:52 -08:00
Adam Szkoda
dce7b31126 ssh signing: better error message when key not in agent
When signing a commit with a SSH key, with the private key missing from
ssh-agent, a confusing error message is produced:

    error: Load key
    "/var/folders/t5/cscwwl_n3n1_8_5j_00x_3t40000gn/T//.git_signing_key_tmpkArSj7":
    invalid format? fatal: failed to write commit object

The temporary file .git_signing_key_tmpkArSj7 created by git contains a
valid *public* key.  The error message comes from `ssh-keygen -Y sign' and
is caused by a fallback mechanism in ssh-keygen whereby it tries to
interpret .git_signing_key_tmpkArSj7 as a *private* key if it can't find in
the agent [1].  A fix is scheduled to be released in OpenSSH 9.1. All that
needs to be done is to pass an additional backward-compatible option -U to
'ssh-keygen -Y sign' call.  With '-U', ssh-keygen always interprets the file
as public key and expects to find the private key in the agent.

As a result, when the private key is missing from the agent, a more accurate
error message gets produced:

    error: Couldn't find key in agent

[1] https://bugzilla.mindrot.org/show_bug.cgi?id=3429

Signed-off-by: Adam Szkoda <adaszko@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-25 08:59:51 -08:00
Taylor Blau
bffc762f87 dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
When using the dir_iterator API, we first stat(2) the base path, and
then use that as a starting point to enumerate the directory's contents.

If the directory contains symbolic links, we will immediately die() upon
encountering them without the `FOLLOW_SYMLINKS` flag. The same is not
true when resolving the top-level directory, though.

As explained in a previous commit, this oversight in 6f054f9fb3
(builtin/clone.c: disallow `--local` clones with symlinks, 2022-07-28)
can be used as an attack vector to include arbitrary files on a victim's
filesystem from outside of the repository.

Prevent resolving top-level symlinks unless the FOLLOW_SYMLINKS flag is
given, which will cause clones of a repository with a symlink'd
"$GIT_DIR/objects" directory to fail.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-24 16:52:16 -08:00
Taylor Blau
cf8f6ce02a clone: delay picking a transport until after get_repo_path()
In the previous commit, t5619 demonstrates an issue where two calls to
`get_repo_path()` could trick Git into using its local clone mechanism
in conjunction with a non-local transport.

That sequence is:

 - the starting state is that the local path https:/example.com/foo is a
   symlink that points to ../../../.git/modules/foo. So it's dangling.

 - get_repo_path() sees that no such path exists (because it's
   dangling), and thus we do not canonicalize it into an absolute path

 - because we're using --separate-git-dir, we create .git/modules/foo.
   Now our symlink is no longer dangling!

 - we pass the url to transport_get(), which sees it as an https URL.

 - we call get_repo_path() again, on the url. This second call was
   introduced by f38aa83f9a (use local cloning if insteadOf makes a
   local URL, 2014-07-17). The idea is that we want to pull the url
   fresh from the remote.c API, because it will apply any aliases.

And of course now it sees that there is a local file, which is a
mismatch with the transport we already selected.

The issue in the above sequence is calling `transport_get()` before
deciding whether or not the repository is indeed local, and not passing
in an absolute path if it is local.

This is reminiscent of a similar bug report in [1], where it was
suggested to perform the `insteadOf` lookup earlier. Taking that
approach may not be as straightforward, since the intent is to store the
original URL in the config, but to actually fetch from the insteadOf
one, so conflating the two early on is a non-starter.

Note: we pass the path returned by `get_repo_path(remote->url[0])`,
which should be the same as `repo_name` (aside from any `insteadOf`
rewrites).

We *could* pass `absolute_pathdup()` of the same argument, which
86521acaca (Bring local clone's origin URL in line with that of a remote
clone, 2008-09-01) indicates may differ depending on the presence of
".git/" for a non-bare repo. That matters for forming relative submodule
paths, but doesn't matter for the second call, since we're just feeding
it to the transport code, which is fine either way.

[1]: https://lore.kernel.org/git/CAMoD=Bi41mB3QRn3JdZL-FGHs4w3C2jGpnJB-CqSndO7FMtfzA@mail.gmail.com/

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-24 16:52:16 -08:00
Taylor Blau
58325b93c5 t5619: demonstrate clone_local() with ambiguous transport
When cloning a repository, Git must determine (a) what transport
mechanism to use, and (b) whether or not the clone is local.

Since f38aa83f9a (use local cloning if insteadOf makes a local URL,
2014-07-17), the latter check happens after the remote has been
initialized, and references the remote's URL instead of the local path.
This is done to make it possible for a `url.<base>.insteadOf` rule to
convert a remote URL into a local one, in which case the `clone_local()`
mechanism should be used.

However, with a specially crafted repository, Git can be tricked into
using a non-local transport while still setting `is_local` to "1" and
using the `clone_local()` optimization. The below test case
demonstrates such an instance, and shows that it can be used to include
arbitrary (known) paths in the working copy of a cloned repository on a
victim's machine[^1], even if local file clones are forbidden by
`protocol.file.allow`.

This happens in a few parts:

 1. We first call `get_repo_path()` to see if the remote is a local
    path. If it is, we replace the repo name with its absolute path.

 2. We then call `transport_get()` on the repo name and decide how to
    access it. If it was turned into an absolute path in the previous
    step, then we should always treat it like a file.

 3. We use `get_repo_path()` again, and set `is_local` as appropriate.
    But it's already too late to rewrite the repo name as an absolute
    path, since we've already fed it to the transport code.

The attack works by including a submodule whose URL corresponds to a
path on disk. In the below example, the repository "sub" is reachable
via the dumb HTTP protocol at (something like):

    http://127.0.0.1:NNNN/dumb/sub.git

However, the path "http:/127.0.0.1:NNNN/dumb" (that is, a top-level
directory called "http:", then nested directories "127.0.0.1:NNNN", and
"dumb") exists within the repository, too.

To determine this, it first picks the appropriate transport, which is
dumb HTTP. It then uses the remote's URL in order to determine whether
the repository exists locally on disk. However, the malicious repository
also contains an embedded stub repository which is the target of a
symbolic link at the local path corresponding to the "sub" repository on
disk (i.e., there is a symbolic link at "http:/127.0.0.1/dumb/sub.git",
pointing to the stub repository via ".git/modules/sub/../../../repo").

This stub repository fools Git into thinking that a local repository
exists at that URL and thus can be cloned locally. The affected call is
in `get_repo_path()`, which in turn calls `get_repo_path_1()`, which
locates a valid repository at that target.

This then causes Git to set the `is_local` variable to "1", and in turn
instructs Git to clone the repository using its local clone optimization
via the `clone_local()` function.

The exploit comes into play because the stub repository's top-level
"$GIT_DIR/objects" directory is a symbolic link which can point to an
arbitrary path on the victim's machine. `clone_local()` resolves the
top-level "objects" directory through a `stat(2)` call, meaning that we
read through the symbolic link and copy or hardlink the directory
contents at the destination of the link.

In other words, we can get steps (1) and (3) to disagree by leveraging
the dangling symlink to pick a non-local transport in the first step,
and then set is_local to "1" in the third step when cloning with
`--separate-git-dir`, which makes the symlink non-dangling.

This can result in data-exfiltration on the victim's machine when
sensitive data is at a known path (e.g., "/home/$USER/.ssh").

The appropriate fix is two-fold:

 - Resolve the transport later on (to avoid using the local
   clone optimization with a non-local transport).

 - Avoid reading through the top-level "objects" directory when
   (correctly) using the clone_local() optimization.

This patch merely demonstrates the issue. The following two patches will
implement each part of the above fix, respectively.

[^1]: Provided that any target directory does not contain symbolic
  links, in which case the changes from 6f054f9fb3 (builtin/clone.c:
  disallow `--local` clones with symlinks, 2022-07-28) will abort the
  clone.

Reported-by: yvvdwf <yvvdwf@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-24 16:52:16 -08:00
Junio C Hamano
5dec958dcf The tenth batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-23 13:39:52 -08:00
Junio C Hamano
ebed06a3e9 Merge branch 'zh/scalar-progress'
"scalar" learned to give progress bar.

* zh/scalar-progress:
  scalar: show progress if stderr refers to a terminal
2023-01-23 13:39:52 -08:00
Junio C Hamano
5287319bf8 Merge branch 'ds/omit-trailing-hash-in-index'
Quickfix for a topic already in 'master'.

* ds/omit-trailing-hash-in-index:
  t1600: fix racy index.skipHash test
2023-01-23 13:39:52 -08:00
Junio C Hamano
019a1031ea Merge branch 'jc/format-patch-v-unleak'
Plug a small leak.

* jc/format-patch-v-unleak:
  format-patch: unleak "-v <num>"
2023-01-23 13:39:52 -08:00
Junio C Hamano
6e0f966efe Merge branch 'sk/win32-close-handle-upon-pthread-join'
Pthread emulation on Win32 leaked thread handle when a thread is
joined.

* sk/win32-close-handle-upon-pthread-join:
  win32: close handles of threads that have been joined
  win32: prepare pthread.c for change by formatting
2023-01-23 13:39:51 -08:00
Junio C Hamano
5427bb4893 Merge branch 'rs/use-enhanced-bre-on-macos'
Newer regex library macOS stopped enabling GNU-like enhanced BRE,
where '\(A\|B\)' works as alternation, unless explicitly asked with
the REG_ENHANCED flag.  "git grep" now can be compiled to do so, to
retain the old behaviour.

* rs/use-enhanced-bre-on-macos:
  use enhanced basic regular expressions on macOS
2023-01-23 13:39:51 -08:00
Junio C Hamano
cd37c45acf Merge branch 'ab/test-env-helper'
Remove "git env--helper" and demote it to a test-tool subcommand.

* ab/test-env-helper:
  env-helper: move this built-in to "test-tool env-helper"
2023-01-23 13:39:51 -08:00
Junio C Hamano
577bff3a81 Merge branch 'kn/attr-from-tree'
"git check-attr" learned to take an optional tree-ish to read the
.gitattributes file from.

* kn/attr-from-tree:
  attr: add flag `--source` to work with tree-ish
  t0003: move setup for `--all` into new block
2023-01-23 13:39:51 -08:00
Junio C Hamano
8a40af9cab Merge branch 'rs/ls-tree-path-expansion-fix'
"git ls-tree --format='%(path) %(path)' $tree $path" showed the
path three times, which has been corrected.

* rs/ls-tree-path-expansion-fix:
  ls-tree: remove dead store and strbuf for quote_c_style()
  ls-tree: fix expansion of repeated %(path)
2023-01-23 13:39:50 -08:00
Junio C Hamano
b269563512 Merge branch 'en/t6426-todo-cleanup'
Test clean-up.

* en/t6426-todo-cleanup:
  t6426: fix TODO about making test more comprehensive
2023-01-23 13:39:50 -08:00
Junio C Hamano
8844c1125e Merge branch 'ab/cache-api-cleanup'
Code clean-up to tighten the use of in-core index in the API.

* ab/cache-api-cleanup:
  cache API: add a "INDEX_STATE_INIT" macro/function, add release_index()
  read-cache.c: refactor set_new_index_sparsity() for subsequent commit
  sparse-index API: BUG() out on NULL ensure_full_index()
  sparse-index.c: expand_to_path() can assume non-NULL "istate"
  builtin/difftool.c: { 0 }-initialize rather than using memset()
2023-01-23 13:39:49 -08:00
Andrei Rybak
70661d288b Documentation: render dash correctly
Three hyphens are rendered verbatim in documentation, so "--" has to be
used to produce a dash.  Fix asciidoc output for dashes.  This is
similar to previous commits f0b922473e (Documentation: render special
characters correctly, 2021-07-29) and de82095a95 (doc
hash-function-transition: fix asciidoc output, 2021-02-05).

Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-23 09:40:14 -08:00
Torsten Bögershausen
5458ba0a4d t0003: call dd with portable blocksize
The command `dd bs=101M count=1` is not portable,
e.g. dd shipped with MacOs does not understand the 'M'.

Use `dd bs=1048576 count=101`, which achives the same, instead.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-22 08:14:40 -08:00
Junio C Hamano
56c8fb1e95 The ninth batch
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-21 17:22:01 -08:00
Junio C Hamano
86ccd39a74 Merge branch 'yc/doc-fetch-fix'
Doc fix.

* yc/doc-fetch-fix:
  doc: fix non-existent config name
2023-01-21 17:22:01 -08:00
Junio C Hamano
30b4e5c888 Merge branch 'ab/bisect-cleanup'
Code clean-up.

* ab/bisect-cleanup:
  bisect: no longer try to clean up left-over `.git/head-name` files
  bisect: remove Cogito-related code
  bisect run: fix the error message
  bisect: verify that a bogus option won't try to start a bisection
  bisect--helper: make the order consistently `argc, argv`
  bisect--helper: simplify exit code computation
2023-01-21 17:22:01 -08:00
Junio C Hamano
38a49aba90 Merge branch 'tl/ls-tree-code-clean-up'
Code clean-up.

* tl/ls-tree-code-clean-up:
  t3104: remove shift code in 'test_ls_tree_format'
  ls-tree: cleanup the redundant SPACE
  ls-tree: make "line_termination" less generic
  ls-tree: fold "show_tree_data" into "cb" struct
  ls-tree: use a "struct options"
  ls-tree: don't use "show_tree_data" for "fast" callbacks
2023-01-21 17:22:00 -08:00
Junio C Hamano
d2917b9099 Merge branch 'ph/parse-date-reduced-precision'
Loosen date parsing heuristics.

* ph/parse-date-reduced-precision:
  date.c: allow ISO 8601 reduced precision times
2023-01-21 17:22:00 -08:00
Junio C Hamano
e28d5d2160 Merge branch 'pw/rebase-exec-cleanup'
Code clean-up.

* pw/rebase-exec-cleanup:
  rebase: cleanup "--exec" option handling
2023-01-21 17:22:00 -08:00
Junio C Hamano
9c2003a6cb Merge branch 'pb/doc-orig-head'
Document ORIG_HEAD a bit more.

* pb/doc-orig-head:
  git-rebase.txt: add a note about 'ORIG_HEAD' being overwritten
  revisions.txt: be explicit about commands writing 'ORIG_HEAD'
  git-merge.txt: mention 'ORIG_HEAD' in the Description
  git-reset.txt: mention 'ORIG_HEAD' in the Description
  git-cherry-pick.txt: do not use 'ORIG_HEAD' in example
2023-01-21 17:22:00 -08:00
Junio C Hamano
b106341d57 Merge branch 'yo/doc-use-more-switch-c'
Doc update.

* yo/doc-use-more-switch-c:
  doc: add "git switch -c" as another option on detached HEAD
2023-01-21 17:22:00 -08:00
Junio C Hamano
df786f6efe Merge branch 'sk/merge-filtering-strategies-micro-optim'
Micro optimization.

* sk/merge-filtering-strategies-micro-optim:
  merge: break out of all_strategy loop when strategy is found
2023-01-21 17:21:59 -08:00
Junio C Hamano
42423c61d9 Merge branch 'jk/interop-error'
Test helper improvement.

* jk/interop-error:
  t/interop: report which vanilla git command failed
2023-01-21 17:21:59 -08:00
Junio C Hamano
f2744aa37e Merge branch 'ar/bisect-doc-update'
Doc update.

* ar/bisect-doc-update:
  git-bisect-lk2009: update nist report link
  git-bisect-lk2009: update java code conventions link
2023-01-21 17:21:59 -08:00
Junio C Hamano
013f168211 Merge branch 'ar/test-cleanup'
Test clean-up.

* ar/test-cleanup:
  t7527: use test_when_finished in 'case insensitive+preserving'
  t6422: drop commented out code
  t6003: uncomment test '--max-age=c3, --topo-order'
2023-01-21 17:21:59 -08:00
Junio C Hamano
c253d61137 Merge branch 'jc/doc-diff-patch.txt'
Doc update.

* jc/doc-diff-patch.txt:
  docs: link generating patch sections
2023-01-21 17:21:58 -08:00
Junio C Hamano
fc2735f427 Merge branch 'es/hooks-and-local-env'
Doc update for environment variables set when hooks are invoked.

* es/hooks-and-local-env:
  githooks: discuss Git operations in foreign repositories
2023-01-21 17:21:58 -08:00
Junio C Hamano
60ce816cb6 Merge branch 'rs/dup-array'
Code cleaning.

* rs/dup-array:
  use DUP_ARRAY
  add DUP_ARRAY
  do full type check in BARF_UNLESS_COPYABLE
  factor out BARF_UNLESS_COPYABLE
  mingw: make argv2 in try_shell_exec() non-const
2023-01-21 17:21:58 -08:00
Junio C Hamano
90c47b3fba Merge branch 'jx/t1301-updates'
Test updates.

* jx/t1301-updates:
  t1301: do not change $CWD in "shared=all" test case
  t1301: use test_when_finished for cleanup
  t1301: fix wrong template dir for git-init
2023-01-21 17:21:58 -08:00
Junio C Hamano
904d404274 The eighth batch
The cURL one hasn't cooked for a week in 'next', but let's fast
track it so that linux-musl CI job would be happy.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-20 15:36:22 -08:00
Junio C Hamano
5970a4b797 Merge branch 'jk/read-object-cleanup'
Code clean-up.

* jk/read-object-cleanup:
  object-file: fix indent-with-space
  packfile: inline custom read_object()
  repo_read_object_file(): stop wrapping read_object_file_extended()
  read_object_file_extended(): drop lookup_replace option
  streaming: inline call to read_object_file_extended()
  object-file: inline calls to read_object()
2023-01-20 15:36:21 -08:00
Junio C Hamano
10925f5e8a Merge branch 'jk/curl-avoid-deprecated-api'
Deal with a few deprecation warning from cURL library.

* jk/curl-avoid-deprecated-api:
  http: support CURLOPT_PROTOCOLS_STR
  http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
  http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
2023-01-20 15:36:21 -08:00
Jeff King
8e4309038f fsck: do not assume NUL-termination of buffers
The fsck code operates on an object buffer represented as a pointer/len
combination. However, the parsing of commits and tags is a little bit
loose; we mostly scan left-to-right through the buffer, without checking
whether we've gone past the length we were given.

This has traditionally been OK because the buffers we feed to fsck
always have an extra NUL after the end of the object content, which ends
any left-to-right scan. That has always been true for objects we read
from the odb, and we made it true for incoming index-pack/unpack-objects
checks in a1e920a0a7 (index-pack: terminate object buffers with NUL,
2014-12-08).

However, we recently added an exception: hash-object asks index_fd() to
do fsck checks. That _may_ have an extra NUL (if we read from a pipe
into a strbuf), but it might not (if we read the contents from the
file). Nor can we just teach it to always add a NUL. We may mmap the
on-disk file, which will not have any extra bytes (if it's a multiple of
the page size). Not to mention that this is a rather subtle assumption
for the fsck code to make.

Instead, let's make sure that the fsck parsers don't ever look past the
size of the buffer they've been given. This _almost_ works already,
thanks to earlier work in 4d0d89755e (Make sure fsck_commit_buffer()
does not run out of the buffer, 2014-09-11). The theory there is that we
check up front whether we have the end of header double-newline
separator. And then any left-to-right scanning we do is OK as long as it
stops when it hits that boundary.

However, we later softened that in 84d18c0bcf (fsck: it is OK for a tag
and a commit to lack the body, 2015-06-28), which allows the
double-newline header to be missing, but does require that the header
ends in a newline. That was OK back then, because of the NUL-termination
guarantees (including the one from a1e920a0a7 mentioned above).

Because 84d18c0bcf guarantees that any header line does end in a
newline, we are still OK with most of the left-to-right scanning. We
only need to take care after completing a line, to check that there is
another line (and we didn't run out of buffer).

Most of these checks are just need to check "buffer < buffer_end" (where
buffer is advanced as we parse) before scanning for the next header
line. But here are a few notes:

  - we don't technically need to check for remaining buffer before
    parsing the very first line ("tree" for a commit, or "object" for a
    tag), because verify_headers() rejects a totally empty buffer. But
    we'll do so in the name of consistency and defensiveness.

  - there are some calls to strchr('\n'). These are actually OK by the
    "the final header line must end in a newline" guarantee from
    verify_headers(). They will always find that rather than run off the
    end of the buffer. Curiously, they do check for a NULL return and
    complain, but I believe that condition can never be reached.

    However, I converted them to use memchr() with a proper size and
    retained the NULL checks. Using memchr() is not much longer and
    makes it more obvious what is going on. Likewise, retaining the NULL
    checks serves as a defensive measure in case my analysis is wrong.

  - commit 9a1a3a4d4c (mktag: allow omitting the header/body \n
    separator, 2021-01-05), does check for the end-of-buffer condition,
    but does so with "!*buffer", relying explicitly on the NUL
    termination. We can accomplish the same thing with a pointer
    comparison. I also folded it into the follow-on conditional that
    checks the contents of the buffer, for consistency with the other
    checks.

  - fsck_ident() uses parse_timestamp(), which is based on strtoumax().
    That function will happily skip past leading whitespace, including
    newlines, which makes it a risk. We can fix this by scanning to the
    first digit ourselves, and then using parse_timestamp() to do the
    actual numeric conversion.

    Note that as a side effect this fixes the fact that we missed
    zero-padded timestamps like "<email>   0123" (whereas we would
    complain about "<email> 0123"). I doubt anybody cares, but I
    mention it here for completeness.

  - fsck_tree() does not need any modifications. It relies on
    decode_tree_entry() to do the actual parsing, and that function
    checks both that there are enough bytes in the buffer to represent
    an entry, and that there is a NUL at the appropriate spot (one
    hash-length from the end; this may not be the NUL for the entry we
    are parsing, but we know that in the worst case, everything from our
    current position to that NUL is a filename, so we won't run out of
    bytes).

In addition to fixing the code itself, we'd like to make sure our rather
subtle assumptions are not violated in the future. So this patch does
two more things:

  - add comments around verify_headers() documenting the link between
    what it checks and the memory safety of the callers. I don't expect
    this code to be modified frequently, but this may help somebody from
    accidentally breaking things.

  - add a thorough set of tests covering truncations at various key
    spots (e.g., for a "tree $oid" line, in the middle of the word
    "tree", right after it, after the space, in the middle of the $oid,
    and right at the end of the line. Most of these are fine already (it
    is only truncating right at the end of the line that is currently
    broken). And some of them are not even possible with the current
    code (we parse "tree " as a unit, so truncating before the space is
    equivalent). But I aimed here to consider the code a black box and
    look for any truncations that would be a problem for a left-to-right
    parser.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 15:39:43 -08:00
Calvin Wan
06a668cb90 fetch: fix duplicate remote parallel fetch bug
Fetching in parallel from a remote group with a duplicated remote results
in the following:

error: cannot lock ref '<ref>': is at <oid> but expected <oid>

This doesn't happen in serial since fetching from the same remote that
has already been fetched from is a noop. Therefore, remove any duplicated
remotes after remote groups are parsed.

Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:41:48 -08:00
Philip Oakley
540e7bc477 doc: pretty-formats note wide char limitations, and add tests
The previous commits added clarifications to the column alignment
placeholders, note that the spaces are optional around the parameters.

Also, a proposed extension [1] to allow hard truncation (without
ellipsis '..') highlighted that the existing code does not play well
with wide characters, such as Asian fonts and emojis.

For example, N wide characters take 2N columns so won't fit an odd number
column width, causing misalignment somewhere.

Further analysis also showed that decomposed characters, e.g. separate
`a` + `umlaut` Unicode code-points may also be mis-counted, in some cases
leaving multiple loose `umlauts` all combined together.

Add some notes about these limitations, and add basic tests to demonstrate
them.

The chosen solution for the tests is to substitute any wide character
that overlaps a splitting boundary for the unicode vertical ellipsis
code point as a rare but 'obvious' substitution.

An alternative could be the substitution with a single dot '.' which
matches regular expression usage, and our two dot ellipsis, and further
in scenarios where the bulk of the text is wide characters, would be
obvious. In mainly 'ascii' scenarios a singleton emoji being substituted
by a dot could be confusing.

It is enough that the tests fail cleanly. The final choice for the
substitute character can be deferred.

[1]
https://lore.kernel.org/git/20221030185614.3842-1-philipoakley@iee.email/

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:35:15 -08:00
Philip Oakley
b5cd634d7a doc: pretty-formats describe use of ellipsis in truncation
Commit a7f01c6b4d (pretty: support truncating in %>, %< and %><,
2013-04-19) added the use of ellipsis when truncating placeholder
values.

Show our 'two dot' ellipsis, and examples for the left, middle and
right truncation to avoid any confusion as to which end of the string
is adjusted. (cf justification and sub-string).

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:35:15 -08:00
Philip Oakley
63792c564c doc: pretty-formats document negative column alignments
Commit 066790d7cb (pretty.c: support <direction>|(<negative number>) forms,
2016-06-16) added the option for right justified column alignment without
updating the documentation.

Add an explanation of its use of negative column values.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:35:15 -08:00
Philip Oakley
8bcb8f8e22 doc: pretty-formats: delineate %<|( parameter values
Commit a57523428b (pretty: support padding placeholders, %< %> and %><,
2013-04-19) introduced column width place holders. It also added
separate column position `%<|(` placeholders for display screen based
placement.

Change the display screen parameter reference from 'N' to 'M' and
corresponding descriptives to make the distinction clearer.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:35:15 -08:00
Philip Oakley
d664a7ad20 doc: pretty-formats: separate parameters from placeholders
Commit a57523428b (pretty: support padding placeholders, %< %> and %><,
2013-04-19) introduced columnated place holders. These placeholders
can be confusing as they contain `<` and `>` characters as part
of their placeholders adjacent to the `<N>` parameters.

Add spaces either side of the `<N>` parameters in the title line.
The code (strtol) will consume any spaces around the number values
(assuming they are passed as a quoted string with spaces).
Note that the spaces are optional.

Subsequent commits will clarify other confusions.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-19 14:35:15 -08:00
Junio C Hamano
221222b278 Sync with 'maint' 2023-01-19 13:49:38 -08:00
Junio C Hamano
844ede312b Sync with maint-2.38
* maint-2.38:
  attr: adjust a mismatched data type
2023-01-19 13:49:08 -08:00
Junio C Hamano
b78628d426 Sync with maint-2.37
* maint-2.37:
  attr: adjust a mismatched data type
2023-01-19 13:48:26 -08:00