Commit Graph

378 Commits

Author SHA1 Message Date
Christian Couder
dba94e3a85 test-bloom: fix missing 'bloom' from usage string
Like 'get_murmur3' and 'generate_filter', 'get_filter_for_commit' is a
subcommand of `test-tool bloom` not of `test-tool` itself.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-05 22:54:34 -07:00
Jeff King
1b4c57fa87 test-bloom: check that we have expected arguments
If "test-tool bloom" is not fed a command, or if arguments are missing
for some commands, it will just segfault. Let's check argc and write a
friendlier usage message.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-23 16:05:29 -07:00
Jeff King
24b7d1e7b0 test-bloom: fix some whitespace issues
Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-23 16:05:29 -07:00
Garima Singh
a759bfa9ee t4216: add end to end tests for git log with Bloom filters
These tests exercises writing commit graph with Bloom filters
and exercises 'git log -- path' with all the applicable
options. They check that the output is the same with and
without Bloom filters, confirm Bloom filters were used by
checking if trace2 statistics were logged correctly.

Also confirms cases where Bloom filters are not used:
1. Multiple path specs,
2. --walk-reflogs (see patch titled 'revision.c: use Bloom filters...'
   for details,
3. If the latest commit graph does not have Bloom filters

Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-06 11:08:37 -07:00
Garima Singh
1217c03e7b commit-graph: reuse existing Bloom filters during write
Add logic to
a) parse Bloom filter information from the commit graph file and,
b) re-use existing Bloom filters.

See Documentation/technical/commit-graph-format for the format in which
the Bloom filter information is written to the commit graph file.

To read Bloom filter for a given commit with lexicographic position
'i' we need to:
1. Read BIDX[i] which essentially gives us the starting index in BDAT for
   filter of commit i+1. It is essentially the index past the end
   of the filter of commit i. It is called end_index in the code.

2. For i>0, read BIDX[i-1] which will give us the starting index in BDAT
   for filter of commit i. It is called the start_index in the code.
   For the first commit, where i = 0, Bloom filter data starts at the
   beginning, just past the header in the BDAT chunk. Hence, start_index
   will be 0.

3. The length of the filter will be end_index - start_index, because
   BIDX[i] gives the cumulative 8-byte words including the ith
   commit's filter.

We toggle whether Bloom filters should be recomputed based on the
compute_if_not_present flag.

Helped-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-06 11:08:37 -07:00
Garima Singh
ed591febb4 bloom.c: core Bloom filter implementation for changed paths.
Add the core implementation for computing Bloom filters for
the paths changed between a commit and it's first parent.

We fill the Bloom filters as (const char *data, int len) pairs
as `struct bloom_filters" within a commit slab.

Filters for commits with no changes and more than 512 changes,
is represented with a filter of length zero. There is no gain
in distinguishing between a computed filter of length zero for
a commit with no changes, and an uncomputed filter for new commits
or for commits with more than 512 changes. The effect on
`git log -- path` is the same in both cases. We will fall back to
the normal diffing algorithm when we can't benefit from the
existence of Bloom filters.

Helped-by: Jeff King <peff@peff.net>
Helped-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jakub Narębski <jnareb@gmail.com>
Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-30 09:59:53 -07:00
Garima Singh
f1294eaf7f bloom.c: introduce core Bloom filter constructs
Introduce the constructs for Bloom filters, Bloom filter keys
and Bloom filter settings.
For details on what Bloom filters are and how they work, refer
to Dr. Derrick Stolee's blog post [1]. It provides a concise
explanation of the adoption of Bloom filters as described in
[2] and [3].

Implementation specifics:
1. We currently use 7 and 10 for the number of hashes and the
   size of each entry respectively. They served as great starting
   values, the mathematical details behind this choice are
   described in [1] and [4]. The implementation, while not
   completely open to it at the moment, is flexible enough to allow
   for tweaking these settings in the future.

   Note: The performance gains we have observed with these values
   are significant enough that we did not need to tweak these
   settings. The performance numbers are included in the cover letter
   of this series and in the commit message of the subsequent commit
   where we use Bloom filters to speed up `git log -- path`.

2. As described in [1] and [3], we do not need 7 independent hashing
   functions. We use the Murmur3 hashing scheme, seed it twice and
   then combine those to procure an arbitrary number of hash values.

3. The filters will be sized according to the number of changes in
   each commit, in multiples of 8 bit words.

[1] Derrick Stolee
      "Supercharging the Git Commit Graph IV: Bloom Filters"
      https://devblogs.microsoft.com/devops/super-charging-the-git-commit-graph-iv-Bloom-filters/

[2] Flavio Bonomi, Michael Mitzenmacher, Rina Panigrahy, Sushil Singh, George Varghese
    "An Improved Construction for Counting Bloom Filters"
    http://theory.stanford.edu/~rinap/papers/esa2006b.pdf
    https://doi.org/10.1007/11841036_61

[3] Peter C. Dillinger and Panagiotis Manolios
    "Bloom Filters in Probabilistic Verification"
    http://www.ccs.neu.edu/home/pete/pub/Bloom-filters-verification.pdf
    https://doi.org/10.1007/978-3-540-30494-4_26

[4] Thomas Mueller Graf, Daniel Lemire
    "Xor Filters: Faster and Smaller Than Bloom and Cuckoo Filters"
    https://arxiv.org/abs/1912.08258

Helped-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jakub Narębski <jnareb@gmail.com>
Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-30 09:59:53 -07:00
Garima Singh
f52207a45c bloom.c: add the murmur3 hash implementation
In preparation for computing changed paths Bloom filters,
implement the Murmur3 hash algorithm as described in [1].
It hashes the given data using the given seed and produces
a uniformly distributed hash value.

[1] https://en.wikipedia.org/wiki/MurmurHash#Algorithm

Helped-by: Derrick Stolee <dstolee@microsoft.com>
Helped-by: Szeder Gábor <szeder.dev@gmail.com>
Reviewed-by: Jakub Narębski <jnareb@gmail.com>
Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-30 09:59:53 -07:00
Junio C Hamano
f8cb64e3d4 Merge branch 'bc/sha-256-part-1-of-4'
SHA-256 transition continues.

* bc/sha-256-part-1-of-4: (22 commits)
  fast-import: add options for rewriting submodules
  fast-import: add a generic function to iterate over marks
  fast-import: make find_marks work on any mark set
  fast-import: add helper function for inserting mark object entries
  fast-import: permit reading multiple marks files
  commit: use expected signature header for SHA-256
  worktree: allow repository version 1
  init-db: move writing repo version into a function
  builtin/init-db: add environment variable for new repo hash
  builtin/init-db: allow specifying hash algorithm on command line
  setup: allow check_repository_format to read repository format
  t/helper: make repository tests hash independent
  t/helper: initialize repository if necessary
  t/helper/test-dump-split-index: initialize git repository
  t6300: make hash algorithm independent
  t6300: abstract away SHA-1-specific constants
  t: use hash-specific lookup tables to define test constants
  repository: require a build flag to use SHA-256
  hex: add functions to parse hex object IDs in any algorithm
  hex: introduce parsing variants taking hash algorithms
  ...
2020-03-26 17:11:20 -07:00
Junio C Hamano
4d0e8996ec Merge branch 'am/real-path-fix'
The real_path() convenience function can easily be misused; with a
bit of code refactoring in the callers' side, its use has been
eliminated.

* am/real-path-fix:
  get_superproject_working_tree(): return strbuf
  real_path_if_valid(): remove unsafe API
  real_path: remove unsafe API
  set_git_dir: fix crash when used with real_path()
2020-03-25 13:57:43 -07:00
Junio C Hamano
c4a09cc9cc Merge branch 'hw/advise-ng'
Revamping of the advise API to allow more systematic enumeration of
advice knobs in the future.

* hw/advise-ng:
  tag: use new advice API to check visibility
  advice: revamp advise API
  advice: change "setupStreamFailure" to "setUpstreamFailure"
  advice: extract vadvise() from advise()
2020-03-25 13:57:41 -07:00
Alexandr Miloslavskiy
3d7747e318 real_path: remove unsafe API
Returning a shared buffer invites very subtle bugs due to reentrancy or
multi-threading, as demonstrated by the previous patch.

There was an unfinished effort to abolish this [1].

Let's finally rid of `real_path()`, using `strbuf_realpath()` instead.

This patch uses a local `strbuf` for most places where `real_path()` was
previously called.

However, two places return the value of `real_path()` to the caller. For
them, a `static` local `strbuf` was added, effectively pushing the
problem one level higher:
    read_gitfile_gently()
    get_superproject_working_tree()

[1] https://lore.kernel.org/git/1480964316-99305-1-git-send-email-bmwill@google.com/

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-10 11:41:40 -07:00
Junio C Hamano
0e0d717537 Merge branch 'pb/am-show-current-patch'
"git am --short-current-patch" is a way to show the piece of e-mail
for the stopped step, which is not suitable to directly feed "git
apply" (it is designed to be a good "git am" input).  It learned a
new option to show only the patch part.

* pb/am-show-current-patch:
  am: support --show-current-patch=diff to retrieve .git/rebase-apply/patch
  am: support --show-current-patch=raw as a synonym for--show-current-patch
  am: convert "resume" variable to a struct
  parse-options: convert "command mode" to a flag
  parse-options: add testcases for OPT_CMDMODE()
2020-03-09 11:21:19 -07:00
Heba Waly
b3b18d1621 advice: revamp advise API
Currently it's very easy for the advice library's callers to miss
checking the visibility step before printing an advice. Also, it makes
more sense for this step to be handled by the advice library.

Add a new advise_if_enabled function that checks the visibility of
advice messages before printing.

Add a new helper advise_enabled to check the visibility of the advice
if the caller needs to carry out complicated processing based on that
value.

A list of advice_settings is added to cache the config variables names
and values, it's intended to replace advice_config[] and the global
variables once we migrate all the callers to use the new APIs.

Signed-off-by: Heba Waly <heba.waly@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-03-05 06:15:02 -08:00
Junio C Hamano
ff41848e99 Merge branch 'rs/micro-cleanups'
Code cleanup.

* rs/micro-cleanups:
  use strpbrk(3) to search for characters from a given set
  quote: use isalnum() to check for alphanumeric characters
2020-03-02 15:07:20 -08:00
Junio C Hamano
d0038f4b31 Merge branch 'bw/remote-rename-update-config'
"git remote rename X Y" needs to adjust configuration variables
(e.g. branch.<name>.remote) whose value used to be X to Y.
branch.<name>.pushRemote is now also updated.

* bw/remote-rename-update-config:
  remote rename/remove: gently handle remote.pushDefault config
  config: provide access to the current line number
  remote rename/remove: handle branch.<name>.pushRemote config values
  remote: clean-up config callback
  remote: clean-up by returning early to avoid one indentation
  pull --rebase/remote rename: document and honor single-letter abbreviations rebase types
2020-02-25 11:18:32 -08:00
brian m. carlson
bf154a8782 t/helper: make repository tests hash independent
This test currently hard-codes the hash algorithm as SHA-1 when calling
repo_set_hash_algo so that the_hash_algo is properly initialized.
However, this does not work with SHA-256 repositories. Read the
repository value that repo_init has read into the local repository
variable and set the algorithm based on that value.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:27 -08:00
brian m. carlson
8dca7f30e4 t/helper: initialize repository if necessary
The repository helper is used in t5318 to read commit graphs whether
we're in a repository or not. However, without a repository, we have no
way to properly initialize the hash algorithm, meaning that the file is
misread.

Fix this by calling setup_git_directory_gently, which will read the
environment variable the testsuite sets to ensure that the correct hash
algorithm is set.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:27 -08:00
brian m. carlson
6946e525ae t/helper/test-dump-split-index: initialize git repository
In this test helper, we read the index.  In order to have the proper
hash algorithm set up, we must call setup_git_directory.  Do so, so that
the test works when extensions.objectFormat is set.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:33:24 -08:00
René Scharfe
2ce6d075fa use strpbrk(3) to search for characters from a given set
We can check if certain characters are present in a string by calling
strchr(3) on each of them, or we can pass them all to a single
strpbrk(3) call.  The latter is shorter, less repetitive and slightly
more efficient, so let's do that instead.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-24 09:30:31 -08:00
Paolo Bonzini
62e7a6f7a1 parse-options: add testcases for OPT_CMDMODE()
Before modifying the implementation, ensure that general operation of
OPT_CMDMODE() and detection of incompatible options are covered.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-20 13:20:40 -08:00
Junio C Hamano
5d55554b1d Merge branch 'mr/show-config-scope'
"git config" learned to show in which "scope", in addition to in
which file, each config setting comes from.

* mr/show-config-scope:
  config: add '--show-scope' to print the scope of a config value
  submodule-config: add subomdule config scope
  config: teach git_config_source to remember its scope
  config: preserve scope in do_git_config_sequence
  config: clarify meaning of command line scoping
  config: split repo scope to local and worktree
  config: make scope_name non-static and rename it
  t1300: create custom config file without special characters
  t1300: fix over-indented HERE-DOCs
  config: fix typo in variable name
2020-02-17 13:22:17 -08:00
Junio C Hamano
53c3be2c29 Merge branch 'tb/commit-graph-object-dir'
The code to compute the commit-graph has been taught to use a more
robust way to tell if two object directories refer to the same
thing.

* tb/commit-graph-object-dir:
  commit-graph.h: use odb in 'load_commit_graph_one_fd_st'
  commit-graph.c: remove path normalization, comparison
  commit-graph.h: store object directory in 'struct commit_graph'
  commit-graph.h: store an odb in 'struct write_commit_graph_context'
  t5318: don't pass non-object directory to '--object-dir'
2020-02-14 12:54:24 -08:00
Junio C Hamano
c9a33e5e5d Merge branch 'kw/fsmonitor-watchman-racefix'
A new version of fsmonitor-watchman hook has been introduced, to
avoid races.

* kw/fsmonitor-watchman-racefix:
  fsmonitor: update documentation for hook version and watchman hooks
  fsmonitor: add fsmonitor hook scripts for version 2
  fsmonitor: handle version 2 of the hooks that will use opaque token
  fsmonitor: change last update timestamp on the index_state to opaque token
2020-02-14 12:54:20 -08:00
Bert Wesarg
f2a2327a4a config: provide access to the current line number
Users are nowadays trained to see message from CLI tools in the form

    <file>:<lno>: …

To be able to give such messages when notifying the user about
configurations in any config file, it is currently only possible to get
the file name (if the value originates from a file to begin with) via
`current_config_name()`. Now it is also possible to query the current line
number for the configuration.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-10 10:52:10 -08:00
Matthew Rogers
a5cb4204b6 config: make scope_name non-static and rename it
To prepare for the upcoming --show-scope option, we require the ability
to convert a config_scope enum to a string.  As this was originally
implemented as a static function 'scope_name()' in
t/helper/test-config.c, we expose it via config.h and give it a less
ambiguous name 'config_scope_name()'

Signed-off-by: Matthew Rogers <mattr94@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-10 10:32:18 -08:00
Taylor Blau
a7df60cac8 commit-graph.h: use odb in 'load_commit_graph_one_fd_st'
Apply a similar treatment as in the previous patch to pass a 'struct
object_directory *' through the 'load_commit_graph_one_fd_st'
initializer, too.

This prevents a potential bug where a pointer comparison is made to a
NULL 'g->odb', which would cause the commit-graph machinery to think
that a pair of commit-graphs belonged to different alternates when in
fact they do not (i.e., in the case of no '--object-dir').

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-04 11:36:51 -08:00
Taylor Blau
ad2dd5bb63 commit-graph.c: remove path normalization, comparison
As of the previous patch, all calls to 'commit-graph.c' functions which
perform path normalization (for e.g., 'get_commit_graph_filename()') are
of the form 'ctx->odb->path', which is always in normalized form.

Now that there are no callers passing non-normalized paths to these
functions, ensure that future callers are bound by the same restrictions
by making these functions take a 'struct object_directory *' instead of
a 'const char *'. To match, replace all calls with arguments of the form
'ctx->odb->path' with 'ctx->odb' To recover the path, functions that
perform path manipulation simply use 'odb->path'.

Further, avoid string comparisons with arguments of the form
'odb->path', and instead prefer raw pointer comparisons, which
accomplish the same effect, but are far less brittle.

This has a pleasant side-effect of making these functions much more
robust to paths that cannot be normalized by 'normalize_path_copy()',
i.e., because they are outside of the current working directory.

For example, prior to this patch, Valgrind reports that the following
uninitialized memory read [1]:

  $ ( cd t && GIT_DIR=../.git valgrind git rev-parse HEAD^ )

because 'normalize_path_copy()' can't normalize '../.git' (since it's
relative to but above of the current working directory) [2].

By using a 'struct object_directory *' directly,
'get_commit_graph_filename()' does not need to normalize, because all
paths are relative to the current working directory since they are
always read from the '->path' of an object directory.

[1]: https://lore.kernel.org/git/20191027042116.GA5801@sigill.intra.peff.net.
[2]: The bug here is that 'get_commit_graph_filename()' returns the
     result of 'normalize_path_copy()' without checking the return
     value.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-02-04 11:36:51 -08:00
Alexandr Miloslavskiy
d0d0a357a1 t: directly test parse_pathspec_file()
Previously, `parse_pathspec_file()` was tested indirectly by invoking
git commands with properly crafted inputs. As demonstrated by the
previous bugfix, testing complicated black boxes indirectly can lead to
tests that silently test the wrong thing.

Introduce direct tests for `parse_pathspec_file()`.

Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-15 12:14:20 -08:00
Kevin Willford
56c6910028 fsmonitor: change last update timestamp on the index_state to opaque token
Some file system monitors might not use or take a timestamp for processing
and in the case of watchman could have race conditions with using a
timestamp. Watchman uses something called a clockid that is used for race
free queries to it. The clockid for watchman is simply a string.

Change the fsmonitor_last_update from being a uint64_t to a char pointer
so that any arbitrary data can be stored in it and passed back to the
fsmonitor.

Signed-off-by: Kevin Willford <Kevin.Willford@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-01-13 14:58:43 -08:00
Junio C Hamano
55d607d85b Merge branch 'js/mingw-inherit-only-std-handles'
Work around a issue where a FD that is left open when spawning a
child process and is kept open in the child can interfere with the
operation in the parent process on Windows.

* js/mingw-inherit-only-std-handles:
  mingw: forbid translating ERROR_SUCCESS to an errno value
  mingw: do set `errno` correctly when trying to restrict handle inheritance
  mingw: restrict file handle inheritance only on Windows 7 and later
  mingw: spawned processes need to inherit only standard handles
  mingw: work around incorrect standard handles
  mingw: demonstrate that all file handles are inherited by child processes
2019-12-10 13:11:42 -08:00
Junio C Hamano
7034cd094b Sync with Git 2.24.1 2019-12-09 22:17:55 -08:00
Johannes Schindelin
67af91c47a Sync with 2.23.1
* maint-2.23: (44 commits)
  Git 2.23.1
  Git 2.22.2
  Git 2.21.1
  mingw: sh arguments need quoting in more circumstances
  mingw: fix quoting of empty arguments for `sh`
  mingw: use MSYS2 quoting even when spawning shell scripts
  mingw: detect when MSYS2's sh is to be spawned more robustly
  t7415: drop v2.20.x-specific work-around
  Git 2.20.2
  t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
  Git 2.19.3
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  ...
2019-12-06 16:31:39 +01:00
Johannes Schindelin
7fd9fd94fb Sync with 2.22.2
* maint-2.22: (43 commits)
  Git 2.22.2
  Git 2.21.1
  mingw: sh arguments need quoting in more circumstances
  mingw: fix quoting of empty arguments for `sh`
  mingw: use MSYS2 quoting even when spawning shell scripts
  mingw: detect when MSYS2's sh is to be spawned more robustly
  t7415: drop v2.20.x-specific work-around
  Git 2.20.2
  t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
  Git 2.19.3
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  ...
2019-12-06 16:31:30 +01:00
Johannes Schindelin
5421ddd8d0 Sync with 2.21.1
* maint-2.21: (42 commits)
  Git 2.21.1
  mingw: sh arguments need quoting in more circumstances
  mingw: fix quoting of empty arguments for `sh`
  mingw: use MSYS2 quoting even when spawning shell scripts
  mingw: detect when MSYS2's sh is to be spawned more robustly
  t7415: drop v2.20.x-specific work-around
  Git 2.20.2
  t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
  Git 2.19.3
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  ...
2019-12-06 16:31:23 +01:00
Johannes Schindelin
fc346cb292 Sync with 2.20.2
* maint-2.20: (36 commits)
  Git 2.20.2
  t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
  Git 2.19.3
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  ...
2019-12-06 16:31:12 +01:00
Johannes Schindelin
d851d94151 Sync with 2.19.3
* maint-2.19: (34 commits)
  Git 2.19.3
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  ...
2019-12-06 16:30:49 +01:00
Johannes Schindelin
7c9fbda6e2 Sync with 2.18.2
* maint-2.18: (33 commits)
  Git 2.18.2
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  is_ntfs_dotgit(): speed it up
  ...
2019-12-06 16:30:38 +01:00
Johannes Schindelin
14af7ed5a9 Sync with 2.17.3
* maint-2.17: (32 commits)
  Git 2.17.3
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  is_ntfs_dotgit(): speed it up
  mingw: disallow backslash characters in tree objects' file names
  ...
2019-12-06 16:29:15 +01:00
Johannes Schindelin
bdfef0492c Sync with 2.16.6
* maint-2.16: (31 commits)
  Git 2.16.6
  test-drop-caches: use `has_dos_drive_prefix()`
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  is_ntfs_dotgit(): speed it up
  mingw: disallow backslash characters in tree objects' file names
  path: safeguard `.git` against NTFS Alternate Streams Accesses
  ...
2019-12-06 16:27:36 +01:00
Johannes Schindelin
68440496c7 test-drop-caches: use has_dos_drive_prefix()
This is a companion patch to 'mingw: handle `subst`-ed "DOS drives"':
use the DOS drive prefix handling that is already provided by
`compat/mingw.c` (and which just learned to handle non-alphabetical
"drive letters").

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-06 16:27:20 +01:00
Johannes Schindelin
9ac92fed5b Sync with 2.15.4
* maint-2.15: (29 commits)
  Git 2.15.4
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  is_ntfs_dotgit(): speed it up
  mingw: disallow backslash characters in tree objects' file names
  path: safeguard `.git` against NTFS Alternate Streams Accesses
  clone --recurse-submodules: prevent name squatting on Windows
  is_ntfs_dotgit(): only verify the leading segment
  ...
2019-12-06 16:27:18 +01:00
Johannes Schindelin
d3ac8c3f27 Sync with 2.14.6
* maint-2.14: (28 commits)
  Git 2.14.6
  mingw: handle `subst`-ed "DOS drives"
  mingw: refuse to access paths with trailing spaces or periods
  mingw: refuse to access paths with illegal characters
  unpack-trees: let merged_entry() pass through do_add_entry()'s errors
  quote-stress-test: offer to test quoting arguments for MSYS2 sh
  t6130/t9350: prepare for stringent Win32 path validation
  quote-stress-test: allow skipping some trials
  quote-stress-test: accept arguments to test via the command-line
  tests: add a helper to stress test argument quoting
  mingw: fix quoting of arguments
  Disallow dubiously-nested submodule git directories
  protect_ntfs: turn on NTFS protection by default
  path: also guard `.gitmodules` against NTFS Alternate Data Streams
  is_ntfs_dotgit(): speed it up
  mingw: disallow backslash characters in tree objects' file names
  path: safeguard `.git` against NTFS Alternate Streams Accesses
  clone --recurse-submodules: prevent name squatting on Windows
  is_ntfs_dotgit(): only verify the leading segment
  test-path-utils: offer to run a protectNTFS/protectHFS benchmark
  ...
2019-12-06 16:26:55 +01:00
Johannes Schindelin
65d30a19de Merge branch 'win32-filenames-cannot-have-trailing-spaces-or-periods'
On Windows, filenames cannot have trailing spaces or periods, when
opening such paths, they are stripped automatically. Read: you can open
the file `README` via the file name `README . . .`. This ambiguity can
be used in combination with other security bugs to cause e.g. remote
code execution during recursive clones. This patch series fixes that.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:37:09 +01:00
Johannes Schindelin
d2c84dad1c mingw: refuse to access paths with trailing spaces or periods
When creating a directory on Windows whose path ends in a space or a
period (or chains thereof), the Win32 API "helpfully" trims those. For
example, `mkdir("abc ");` will return success, but actually create a
directory called `abc` instead.

This stems back to the DOS days, when all file names had exactly 8
characters plus exactly 3 characters for the file extension, and the
only way to have shorter names was by padding with spaces.

Sadly, this "helpful" behavior is a bit inconsistent: after a successful
`mkdir("abc ");`, a `mkdir("abc /def")` will actually _fail_ (because
the directory `abc ` does not actually exist).

Even if it would work, we now have a serious problem because a Git
repository could contain directories `abc` and `abc `, and on Windows,
they would be "merged" unintentionally.

As these paths are illegal on Windows, anyway, let's disallow any
accesses to such paths on that Operating System.

For practical reasons, this behavior is still guarded by the
config setting `core.protectNTFS`: it is possible (and at least two
regression tests make use of it) to create commits without involving the
worktree. In such a scenario, it is of course possible -- even on
Windows -- to create such file names.

Among other consequences, this patch disallows submodules' paths to end
in spaces on Windows (which would formerly have confused Git enough to
try to write into incorrect paths, anyway).

While this patch does not fix a vulnerability on its own, it prevents an
attack vector that was exploited in demonstrations of a number of
recently-fixed security bugs.

The regression test added to `t/t7417-submodule-path-url.sh` reflects
that attack vector.

Note that we have to adjust the test case "prevent git~1 squatting on
Windows" in `t/t7415-submodule-names.sh` because of a very subtle issue.
It tries to clone two submodules whose names differ only in a trailing
period character, and as a consequence their git directories differ in
the same way. Previously, when Git tried to clone the second submodule,
it thought that the git directory already existed (because on Windows,
when you create a directory with the name `b.` it actually creates `b`),
but with this patch, the first submodule's clone will fail because of
the illegal name of the git directory. Therefore, when cloning the
second submodule, Git will take a different code path: a fresh clone
(without an existing git directory). Both code paths fail to clone the
second submodule, both because the the corresponding worktree directory
exists and is not empty, but the error messages are worded differently.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:37:06 +01:00
Johannes Schindelin
379e51d1ae quote-stress-test: offer to test quoting arguments for MSYS2 sh
It is unfortunate that we need to quote arguments differently on
Windows, depending whether we build a command-line for MSYS2's `sh` or
for other Windows executables.

We already have a test helper to verify the latter, with this patch we
can also verify the former.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:37:06 +01:00
Johannes Schindelin
7530a6287e quote-stress-test: allow skipping some trials
When the, say, 93rd trial run fails, it is a good idea to have a way to
skip the first 92 trials and dig directly into the 93rd in a debugger.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:37:06 +01:00
Johannes Schindelin
55953c77c0 quote-stress-test: accept arguments to test via the command-line
When the stress test reported a problem with quoting certain arguments,
it is helpful to have a facility to play with those arguments in order
to find out whether variations of those arguments are affected, too.

Let's allow `test-run-command quote-stress-test -- <args>` to be used
for that purpose.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:36:53 +01:00
Garima Singh
ad15592529 tests: add a helper to stress test argument quoting
On Windows, we have to do all the command-line argument quoting
ourselves. Worse: we have to have two versions of said quoting, one for
MSYS2 programs (which have their own dequoting rules) and the rest.

We care mostly about the rest, and to make sure that that works, let's
have a stress test that comes up with all kinds of awkward arguments,
verifying that a spawned sub-process receives those unharmed.

Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:36:52 +01:00
Garima Singh
a62f9d1ace test-path-utils: offer to run a protectNTFS/protectHFS benchmark
In preparation to flipping the default on `core.protectNTFS`, let's have
some way to measure the speed impact of this config setting reliably
(and for comparison, the `core.protectHFS` config setting).

For now, this is a manual performance benchmark:

	./t/helper/test-path-utils protect_ntfs_hfs [arguments...]

where the arguments are an optional number of file names to test with,
optionally followed by minimum and maximum length of the random file
names. The default values are one million, 3 and 20, respectively.

Just like `sqrti()` in `bisect.c`, we introduce a very simple function
to approximation the square root of a given value, in order to avoid
having to introduce the first user of `<math.h>` in Git's source code.

Note: this is _not_ implemented as a Unix shell script in t/perf/
because we really care about _very_ precise timings here, and Unix shell
scripts are simply unsuited for precise and consistent benchmarking.

Signed-off-by: Garima Singh <garima.singh@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2019-12-05 15:36:40 +01:00