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Author SHA1 Message Date
Junio C Hamano 5f22dcc02d Sync with Git 2.32.5 2022-12-13 21:13:11 +09:00
Junio C Hamano 8a755eddf5 Sync with Git 2.31.6 2022-12-13 21:09:40 +09:00
Junio C Hamano 16128765d7 Git 2.30.7
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Sync with Git 2.30.7
2022-12-13 21:02:20 +09:00
Patrick Steinhardt 3c50032ff5 attr: ignore overly large gitattributes files
Similar as with the preceding commit, start ignoring gitattributes files
that are overly large to protect us against out-of-bounds reads and
writes caused by integer overflows. Unfortunately, we cannot just define
"overly large" in terms of any preexisting limits in the codebase.

Instead, we choose a very conservative limit of 100MB. This is plenty of
room for specifying gitattributes, and incidentally it is also the limit
for blob sizes for GitHub. While we don't want GitHub to dictate limits
here, it is still sensible to use this fact for an informed decision
given that it is hosting a huge set of repositories. Furthermore, over
at GitLab we scanned a subset of repositories for their root-level
attribute files. We found that 80% of them have a gitattributes file
smaller than 100kB, 99.99% have one smaller than 1MB, and only a single
repository had one that was almost 3MB in size. So enforcing a limit of
100MB seems to give us ample of headroom.

With this limit in place we can be reasonably sure that there is no easy
way to exploit the gitattributes file via integer overflows anymore.
Furthermore, it protects us against resource exhaustion caused by
allocating the in-memory data structures required to represent the
parsed attributes.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:50:03 +09:00
Patrick Steinhardt dfa6b32b5e attr: ignore attribute lines exceeding 2048 bytes
There are two different code paths to read gitattributes: once via a
file, and once via the index. These two paths used to behave differently
because when reading attributes from a file, we used fgets(3P) with a
buffer size of 2kB. Consequentially, we silently truncate line lengths
when lines are longer than that and will then parse the remainder of the
line as a new pattern. It goes without saying that this is entirely
unexpected, but it's even worse that the behaviour depends on how the
gitattributes are parsed.

While this is simply wrong, the silent truncation saves us with the
recently discovered vulnerabilities that can cause out-of-bound writes
or reads with unreasonably long lines due to integer overflows. As the
common path is to read gitattributes via the worktree file instead of
via the index, we can assume that any gitattributes file that had lines
longer than that is already broken anyway. So instead of lifting the
limit here, we can double down on it to fix the vulnerabilities.

Introduce an explicit line length limit of 2kB that is shared across all
paths that read attributes and ignore any line that hits this limit
while printing a warning.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:33:07 +09:00
Patrick Steinhardt d74b1fd54f attr: fix silently splitting up lines longer than 2048 bytes
When reading attributes from a file we use fgets(3P) with a buffer size
of 2048 bytes. This means that as soon as a line exceeds the buffer size
we split it up into multiple parts and parse each of them as a separate
pattern line. This is of course not what the user intended, and even
worse the behaviour is inconsistent with how we read attributes from the
index.

Fix this bug by converting the code to use `strbuf_getline()` instead.
This will indeed read in the whole line, which may theoretically lead to
an out-of-memory situation when the gitattributes file is huge. We're
about to reject any gitattributes files larger than 100MB in the next
commit though, which makes this less of a concern.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:29:30 +09:00
Patrick Steinhardt a60a66e409 attr: harden allocation against integer overflows
When parsing an attributes line, we need to allocate an array that holds
all attributes specified for the given file pattern. The calculation to
determine the number of bytes that need to be allocated was prone to an
overflow though when there was an unreasonable amount of attributes.

Harden the allocation by instead using the `st_` helper functions that
cause us to die when we hit an integer overflow.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt e1e12e97ac attr: fix integer overflow with more than INT_MAX macros
Attributes have a field that tracks the position in the `all_attrs`
array they're stored inside. This field gets set via `hashmap_get_size`
when adding the attribute to the global map of attributes. But while the
field is of type `int`, the value returned by `hashmap_get_size` is an
`unsigned int`. It can thus happen that the value overflows, where we
would now dereference teh `all_attrs` array at an out-of-bounds value.

We do have a sanity check for this overflow via an assert that verifies
the index matches the new hashmap's size. But asserts are not a proper
mechanism to detect against any such overflows as they may not in fact
be compiled into production code.

Fix this by using an `unsigned int` to track the index and convert the
assert to a call `die()`.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt 447ac906e1 attr: fix out-of-bounds read with unreasonable amount of patterns
The `struct attr_stack` tracks the stack of all patterns together with
their attributes. When parsing a gitattributes file that has more than
2^31 such patterns though we may trigger multiple out-of-bounds reads on
64 bit platforms. This is because while the `num_matches` variable is an
unsigned integer, we always use a signed integer to iterate over them.

I have not been able to reproduce this issue due to memory constraints
on my systems. But despite the out-of-bounds reads, the worst thing that
can seemingly happen is to call free(3P) with a garbage pointer when
calling `attr_stack_free()`.

Fix this bug by using unsigned integers to iterate over the array. While
this makes the iteration somewhat awkward when iterating in reverse, it
is at least better than knowingly running into an out-of-bounds read.
While at it, convert the call to `ALLOC_GROW` to use `ALLOC_GROW_BY`
instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt 34ace8bad0 attr: fix out-of-bounds write when parsing huge number of attributes
It is possible to trigger an integer overflow when parsing attribute
names when there are more than 2^31 of them for a single pattern. This
can either lead to us dying due to trying to request too many bytes:

     blob=$(perl -e 'print "f" . " a=" x 2147483649' | git hash-object -w --stdin)
     git update-index --add --cacheinfo 100644,$blob,.gitattributes
     git attr-check --all file

    =================================================================
    ==1022==ERROR: AddressSanitizer: requested allocation size 0xfffffff800000032 (0xfffffff800001038 after adjustments for alignment, red zones etc.) exceeds maximum supported size of 0x10000000000 (thread T0)
        #0 0x7fd3efabf411 in __interceptor_calloc /usr/src/debug/gcc/libsanitizer/asan/asan_malloc_linux.cpp:77
        #1 0x5563a0a1e3d3 in xcalloc wrapper.c:150
        #2 0x5563a058d005 in parse_attr_line attr.c:384
        #3 0x5563a058e661 in handle_attr_line attr.c:660
        #4 0x5563a058eddb in read_attr_from_index attr.c:769
        #5 0x5563a058ef12 in read_attr attr.c:797
        #6 0x5563a058f24c in bootstrap_attr_stack attr.c:867
        #7 0x5563a058f4a3 in prepare_attr_stack attr.c:902
        #8 0x5563a05905da in collect_some_attrs attr.c:1097
        #9 0x5563a059093d in git_all_attrs attr.c:1128
        #10 0x5563a02f636e in check_attr builtin/check-attr.c:67
        #11 0x5563a02f6c12 in cmd_check_attr builtin/check-attr.c:183
        #12 0x5563a02aa993 in run_builtin git.c:466
        #13 0x5563a02ab397 in handle_builtin git.c:721
        #14 0x5563a02abb2b in run_argv git.c:788
        #15 0x5563a02ac991 in cmd_main git.c:926
        #16 0x5563a05432bd in main common-main.c:57
        #17 0x7fd3ef82228f  (/usr/lib/libc.so.6+0x2328f)

    ==1022==HINT: if you don't care about these errors you may set allocator_may_return_null=1
    SUMMARY: AddressSanitizer: allocation-size-too-big /usr/src/debug/gcc/libsanitizer/asan/asan_malloc_linux.cpp:77 in __interceptor_calloc
    ==1022==ABORTING

Or, much worse, it can lead to an out-of-bounds write because we
underallocate and then memcpy(3P) into an array:

    perl -e '
        print "A " . "\rh="x2000000000;
        print "\rh="x2000000000;
        print "\rh="x294967294 . "\n"
    ' >.gitattributes
    git add .gitattributes
    git commit -am "evil attributes"

    $ git clone --quiet /path/to/repo
    =================================================================
    ==15062==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x602000002550 at pc 0x5555559884d5 bp 0x7fffffffbc60 sp 0x7fffffffbc58
    WRITE of size 8 at 0x602000002550 thread T0
        #0 0x5555559884d4 in parse_attr_line attr.c:393
        #1 0x5555559884d4 in handle_attr_line attr.c:660
        #2 0x555555988902 in read_attr_from_index attr.c:784
        #3 0x555555988902 in read_attr_from_index attr.c:747
        #4 0x555555988a1d in read_attr attr.c:800
        #5 0x555555989b0c in bootstrap_attr_stack attr.c:882
        #6 0x555555989b0c in prepare_attr_stack attr.c:917
        #7 0x555555989b0c in collect_some_attrs attr.c:1112
        #8 0x55555598b141 in git_check_attr attr.c:1126
        #9 0x555555a13004 in convert_attrs convert.c:1311
        #10 0x555555a95e04 in checkout_entry_ca entry.c:553
        #11 0x555555d58bf6 in checkout_entry entry.h:42
        #12 0x555555d58bf6 in check_updates unpack-trees.c:480
        #13 0x555555d5eb55 in unpack_trees unpack-trees.c:2040
        #14 0x555555785ab7 in checkout builtin/clone.c:724
        #15 0x555555785ab7 in cmd_clone builtin/clone.c:1384
        #16 0x55555572443c in run_builtin git.c:466
        #17 0x55555572443c in handle_builtin git.c:721
        #18 0x555555727872 in run_argv git.c:788
        #19 0x555555727872 in cmd_main git.c:926
        #20 0x555555721fa0 in main common-main.c:57
        #21 0x7ffff73f1d09 in __libc_start_main ../csu/libc-start.c:308
        #22 0x555555723f39 in _start (git+0x1cff39)

    0x602000002552 is located 0 bytes to the right of 2-byte region [0x602000002550,0x602000002552) allocated by thread T0 here:
        #0 0x7ffff768c037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
        #1 0x555555d7fff7 in xcalloc wrapper.c:150
        #2 0x55555598815f in parse_attr_line attr.c:384
        #3 0x55555598815f in handle_attr_line attr.c:660
        #4 0x555555988902 in read_attr_from_index attr.c:784
        #5 0x555555988902 in read_attr_from_index attr.c:747
        #6 0x555555988a1d in read_attr attr.c:800
        #7 0x555555989b0c in bootstrap_attr_stack attr.c:882
        #8 0x555555989b0c in prepare_attr_stack attr.c:917
        #9 0x555555989b0c in collect_some_attrs attr.c:1112
        #10 0x55555598b141 in git_check_attr attr.c:1126
        #11 0x555555a13004 in convert_attrs convert.c:1311
        #12 0x555555a95e04 in checkout_entry_ca entry.c:553
        #13 0x555555d58bf6 in checkout_entry entry.h:42
        #14 0x555555d58bf6 in check_updates unpack-trees.c:480
        #15 0x555555d5eb55 in unpack_trees unpack-trees.c:2040
        #16 0x555555785ab7 in checkout builtin/clone.c:724
        #17 0x555555785ab7 in cmd_clone builtin/clone.c:1384
        #18 0x55555572443c in run_builtin git.c:466
        #19 0x55555572443c in handle_builtin git.c:721
        #20 0x555555727872 in run_argv git.c:788
        #21 0x555555727872 in cmd_main git.c:926
        #22 0x555555721fa0 in main common-main.c:57
        #23 0x7ffff73f1d09 in __libc_start_main ../csu/libc-start.c:308

    SUMMARY: AddressSanitizer: heap-buffer-overflow attr.c:393 in parse_attr_line
    Shadow bytes around the buggy address:
      0x0c047fff8450: fa fa 00 02 fa fa 00 07 fa fa fd fd fa fa 00 00
      0x0c047fff8460: fa fa 02 fa fa fa fd fd fa fa 00 06 fa fa 05 fa
      0x0c047fff8470: fa fa fd fd fa fa 00 02 fa fa 06 fa fa fa 05 fa
      0x0c047fff8480: fa fa 07 fa fa fa fd fd fa fa 00 01 fa fa 00 02
      0x0c047fff8490: fa fa 00 03 fa fa 00 fa fa fa 00 01 fa fa 00 03
    =>0x0c047fff84a0: fa fa 00 01 fa fa 00 02 fa fa[02]fa fa fa fa fa
      0x0c047fff84b0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
      0x0c047fff84c0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
      0x0c047fff84d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
      0x0c047fff84e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
      0x0c047fff84f0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
    Shadow byte legend (one shadow byte represents 8 application bytes):
      Addressable:           00
      Partially addressable: 01 02 03 04 05 06 07
      Heap left redzone:       fa
      Freed heap region:       fd
      Stack left redzone:      f1
      Stack mid redzone:       f2
      Stack right redzone:     f3
      Stack after return:      f5
      Stack use after scope:   f8
      Global redzone:          f9
      Global init order:       f6
      Poisoned by user:        f7
      Container overflow:      fc
      Array cookie:            ac
      Intra object redzone:    bb
      ASan internal:           fe
      Left alloca redzone:     ca
      Right alloca redzone:    cb
      Shadow gap:              cc
    ==15062==ABORTING

Fix this bug by using `size_t` instead to count the number of attributes
so that this value cannot reasonably overflow without running out of
memory before already.

Reported-by: Markus Vervier <markus.vervier@x41-dsec.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt 2455720950 attr: fix integer overflow when parsing huge attribute names
It is possible to trigger an integer overflow when parsing attribute
names that are longer than 2^31 bytes because we assign the result of
strlen(3P) to an `int` instead of to a `size_t`. This can lead to an
abort in vsnprintf(3P) with the following reproducer:

    blob=$(perl -e 'print "A " . "B"x2147483648 . "\n"' | git hash-object -w --stdin)
    git update-index --add --cacheinfo 100644,$blob,.gitattributes
    git check-attr --all path

    BUG: strbuf.c:400: your vsnprintf is broken (returned -1)

But furthermore, assuming that the attribute name is even longer than
that, it can cause us to silently truncate the attribute and thus lead
to wrong results.

Fix this integer overflow by using a `size_t` instead. This fixes the
silent truncation of attribute names, but it only partially fixes the
BUG we hit: even though the initial BUG is fixed, we can still hit a BUG
when parsing invalid attribute lines via `report_invalid_attr()`.

This is due to an underlying design issue in vsnprintf(3P) which only
knows to return an `int`, and thus it may always overflow with large
inputs. This issue is benign though: the worst that can happen is that
the error message is misreported to be either truncated or too long, but
due to the buffer being NUL terminated we wouldn't ever do an
out-of-bounds read here.

Reported-by: Markus Vervier <markus.vervier@x41-dsec.de>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt 8d0d48cf21 attr: fix out-of-bounds read with huge attribute names
There is an out-of-bounds read possible when parsing gitattributes that
have an attribute that is 2^31+1 bytes long. This is caused due to an
integer overflow when we assign the result of strlen(3P) to an `int`,
where we use the wrapped-around value in a subsequent call to
memcpy(3P). The following code reproduces the issue:

    blob=$(perl -e 'print "a" x 2147483649 . " attr"' | git hash-object -w --stdin)
    git update-index --add --cacheinfo 100644,$blob,.gitattributes
    git check-attr --all file

    AddressSanitizer:DEADLYSIGNAL
    =================================================================
    ==8451==ERROR: AddressSanitizer: SEGV on unknown address 0x7f93efa00800 (pc 0x7f94f1f8f082 bp 0x7ffddb59b3a0 sp 0x7ffddb59ab28 T0)
    ==8451==The signal is caused by a READ memory access.
        #0 0x7f94f1f8f082  (/usr/lib/libc.so.6+0x176082)
        #1 0x7f94f2047d9c in __interceptor_strspn /usr/src/debug/gcc/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:752
        #2 0x560e190f7f26 in parse_attr_line attr.c:375
        #3 0x560e190f9663 in handle_attr_line attr.c:660
        #4 0x560e190f9ddd in read_attr_from_index attr.c:769
        #5 0x560e190f9f14 in read_attr attr.c:797
        #6 0x560e190fa24e in bootstrap_attr_stack attr.c:867
        #7 0x560e190fa4a5 in prepare_attr_stack attr.c:902
        #8 0x560e190fb5dc in collect_some_attrs attr.c:1097
        #9 0x560e190fb93f in git_all_attrs attr.c:1128
        #10 0x560e18e6136e in check_attr builtin/check-attr.c:67
        #11 0x560e18e61c12 in cmd_check_attr builtin/check-attr.c:183
        #12 0x560e18e15993 in run_builtin git.c:466
        #13 0x560e18e16397 in handle_builtin git.c:721
        #14 0x560e18e16b2b in run_argv git.c:788
        #15 0x560e18e17991 in cmd_main git.c:926
        #16 0x560e190ae2bd in main common-main.c:57
        #17 0x7f94f1e3c28f  (/usr/lib/libc.so.6+0x2328f)
        #18 0x7f94f1e3c349 in __libc_start_main (/usr/lib/libc.so.6+0x23349)
        #19 0x560e18e110e4 in _start ../sysdeps/x86_64/start.S:115

    AddressSanitizer can not provide additional info.
    SUMMARY: AddressSanitizer: SEGV (/usr/lib/libc.so.6+0x176082)
    ==8451==ABORTING

Fix this bug by converting the variable to a `size_t` instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Patrick Steinhardt eb22e7dfa2 attr: fix overflow when upserting attribute with overly long name
The function `git_attr_internal()` is called to upsert attributes into
the global map. And while all callers pass a `size_t`, the function
itself accepts an `int` as the attribute name's length. This can lead to
an integer overflow in case the attribute name is longer than `INT_MAX`.

Now this overflow seems harmless as the first thing we do is to call
`attr_name_valid()`, and that function only succeeds in case all chars
in the range of `namelen` match a certain small set of chars. We thus
can't do an out-of-bounds read as NUL is not part of that set and all
strings passed to this function are NUL-terminated. And furthermore, we
wouldn't ever read past the current attribute name anyway due to the
same reason. And if validation fails we will return early.

On the other hand it feels fragile to rely on this behaviour, even more
so given that we pass `namelen` to `FLEX_ALLOC_MEM()`. So let's instead
just do the correct thing here and accept a `size_t` as line length.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-12-05 15:14:16 +09:00
Andrei Rybak abcb66c614 *: fix typos which duplicate a word
Fix typos in documentation, code comments, and RelNotes which repeat
various words.  In trivial cases, just delete the duplicated word and
rewrap text, if needed.  Reword the affected sentence in
Documentation/RelNotes/1.8.4.txt for it to make sense.

Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-14 10:16:06 +09:00
Junio C Hamano 8e97852919 Merge branch 'ds/sparse-index-protections'
Builds on top of the sparse-index infrastructure to mark operations
that are not ready to mark with the sparse index, causing them to
fall back on fully-populated index that they always have worked with.

* ds/sparse-index-protections: (47 commits)
  name-hash: use expand_to_path()
  sparse-index: expand_to_path()
  name-hash: don't add directories to name_hash
  revision: ensure full index
  resolve-undo: ensure full index
  read-cache: ensure full index
  pathspec: ensure full index
  merge-recursive: ensure full index
  entry: ensure full index
  dir: ensure full index
  update-index: ensure full index
  stash: ensure full index
  rm: ensure full index
  merge-index: ensure full index
  ls-files: ensure full index
  grep: ensure full index
  fsck: ensure full index
  difftool: ensure full index
  commit: ensure full index
  checkout: ensure full index
  ...
2021-04-30 13:50:26 +09:00
Derrick Stolee 847a9e5d4f *: remove 'const' qualifier for struct index_state
Several methods specify that they take a 'struct index_state' pointer
with the 'const' qualifier because they intend to only query the data,
not change it. However, we will be introducing a step very low in the
method stack that might modify a sparse-index to become a full index in
the case that our queries venture inside a sparse-directory entry.

This change only removes the 'const' qualifiers that are necessary for
the following change which will actually modify the implementation of
index_name_stage_pos().

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-14 13:46:00 -07:00
Junio C Hamano 204333b015 Merge branch 'jk/open-dotgitx-with-nofollow'
It does not make sense to make ".gitattributes", ".gitignore" and
".mailmap" symlinks, as they are supposed to be usable from the
object store (think: bare repositories where HEAD:.mailmap etc. are
used).  When these files are symbolic links, we used to read the
contents of the files pointed by them by mistake, which has been
corrected.

* jk/open-dotgitx-with-nofollow:
  mailmap: do not respect symlinks for in-tree .mailmap
  exclude: do not respect symlinks for in-tree .gitignore
  attr: do not respect symlinks for in-tree .gitattributes
  exclude: add flags parameter to add_patterns()
  attr: convert "macro_ok" into a flags field
  add open_nofollow() helper
2021-03-22 14:00:22 -07:00
René Scharfe ca56dadb4b use CALLOC_ARRAY
Add and apply a semantic patch for converting code that open-codes
CALLOC_ARRAY to use it instead.  It shortens the code and infers the
element size automatically.

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-13 16:00:09 -08:00
Jeff King 2ef579e261 attr: do not respect symlinks for in-tree .gitattributes
The attributes system may sometimes read in-tree files from the
filesystem, and sometimes from the index. In the latter case, we do not
resolve symbolic links (and are not likely to ever start doing so).
Let's open filesystem links with O_NOFOLLOW so that the two cases behave
consistently.

As a bonus, this means that git will not follow such symlinks to read
and parse out-of-tree paths. In some cases this could have security
implications, as a malicious repository can cause Git to open and read
arbitrary files. It could already feed arbitrary content to the parser,
but in certain setups it might be able to exfiltrate data from those
paths (e.g., if an automated service operating on the malicious repo
reveals its stderr to an attacker).

Note that O_NOFOLLOW only prevents following links for the path itself,
not intermediate directories in the path.  At first glance, it seems
like

  ln -s /some/path in-repo

might still look at "in-repo/.gitattributes", following the symlink to
"/some/path/.gitattributes". However, if "in-repo" is a symbolic link,
then we know that it has no git paths below it, and will never look at
its .gitattributes file.

We will continue to support out-of-tree symbolic links (e.g., in
$GIT_DIR/info/attributes); this just affects in-tree links. When a
symbolic link is encountered, the contents are ignored and a warning is
printed. POSIX specifies ELOOP in this case, so the user would generally
see something like:

  warning: unable to access '.gitattributes': Too many levels of symbolic links

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 09:41:33 -08:00
Jeff King dbf387d550 attr: convert "macro_ok" into a flags field
The attribute code can have a rather deep callstack, through
which we have to pass the "macro_ok" flag. In anticipation
of adding other flags, let's convert this to a generic
bit-field.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-16 09:41:32 -08:00
Elijah Newren b19315d8ab Use new HASHMAP_INIT macro to simplify hashmap initialization
Now that hashamp has lazy initialization and a HASHMAP_INIT macro,
hashmaps allocated on the stack can be initialized without a call to
hashmap_init() and in some cases makes the code a bit shorter.  Convert
some callsites over to take advantage of this.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-11-11 12:55:27 -08:00
Heba Waly 3a1b3415d9 attr: move doc to attr.h
Move the documentation from Documentation/technical/api-gitattributes.txt
to attr.h as it's easier for the developers to find the usage
information beside the code instead of looking for it in another doc file.

Also documentation/technical/api-gitattributes.txt is removed because the
information it has is now redundant and it'll be hard to keep it up to
date and synchronized with the documentation in the header file.

Signed-off-by: Heba Waly <heba.waly@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-11-18 15:21:28 +09:00
Junio C Hamano 5efabc7ed9 Merge branch 'ew/hashmap'
Code clean-up of the hashmap API, both users and implementation.

* ew/hashmap:
  hashmap_entry: remove first member requirement from docs
  hashmap: remove type arg from hashmap_{get,put,remove}_entry
  OFFSETOF_VAR macro to simplify hashmap iterators
  hashmap: introduce hashmap_free_entries
  hashmap: hashmap_{put,remove} return hashmap_entry *
  hashmap: use *_entry APIs for iteration
  hashmap_cmp_fn takes hashmap_entry params
  hashmap_get{,_from_hash} return "struct hashmap_entry *"
  hashmap: use *_entry APIs to wrap container_of
  hashmap_get_next returns "struct hashmap_entry *"
  introduce container_of macro
  hashmap_put takes "struct hashmap_entry *"
  hashmap_remove takes "const struct hashmap_entry *"
  hashmap_get takes "const struct hashmap_entry *"
  hashmap_add takes "struct hashmap_entry *"
  hashmap_get_next takes "const struct hashmap_entry *"
  hashmap_entry_init takes "struct hashmap_entry *"
  packfile: use hashmap_entry in delta_base_cache_entry
  coccicheck: detect hashmap_entry.hash assignment
  diff: use hashmap_entry_init on moved_entry.ent
2019-10-15 13:48:02 +09:00
Eric Wong e2b5038d87 hashmap_entry: remove first member requirement from docs
Comments stating that "struct hashmap_entry" must be the first
member in a struct are no longer valid.

Suggested-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:12 +09:00
Eric Wong 404ab78e39 hashmap: remove type arg from hashmap_{get,put,remove}_entry
Since these macros already take a `keyvar' pointer of a known type,
we can rely on OFFSETOF_VAR to get the correct offset without
relying on non-portable `__typeof__' and `offsetof'.

Argument order is also rearranged, so `keyvar' and `member' are
sequential as they are used as: `keyvar->member'

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:12 +09:00
Eric Wong 23dee69f53 OFFSETOF_VAR macro to simplify hashmap iterators
While we cannot rely on a `__typeof__' operator being portable
to use with `offsetof'; we can calculate the pointer offset
using an existing pointer and the address of a member using
pointer arithmetic for compilers without `__typeof__'.

This allows us to simplify usage of hashmap iterator macros
by not having to specify a type when a pointer of that type
is already given.

In the future, list iterator macros (e.g. list_for_each_entry)
may also be implemented using OFFSETOF_VAR to save hackers the
trouble of using container_of/list_entry macros and without
relying on non-portable `__typeof__'.

v3: use `__typeof__' to avoid clang warnings

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:11 +09:00
Eric Wong 87571c3f71 hashmap: use *_entry APIs for iteration
Inspired by list_for_each_entry in the Linux kernel.
Once again, these are somewhat compromised usability-wise
by compilers lacking __typeof__ support.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:11 +09:00
Eric Wong 939af16eac hashmap_cmp_fn takes hashmap_entry params
Another step in eliminating the requirement of hashmap_entry
being the first member of a struct.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:11 +09:00
Eric Wong f23a465132 hashmap_get{,_from_hash} return "struct hashmap_entry *"
Update callers to use hashmap_get_entry, hashmap_get_entry_from_hash
or container_of as appropriate.

This is another step towards eliminating the requirement of
hashmap_entry being the first field in a struct.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:11 +09:00
Eric Wong b6c5241606 hashmap_get takes "const struct hashmap_entry *"
This is less error-prone than "const void *" as the compiler
now detects invalid types being passed.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:10 +09:00
Eric Wong b94e5c1df6 hashmap_add takes "struct hashmap_entry *"
This is less error-prone than "void *" as the compiler now
detects invalid types being passed.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:10 +09:00
Eric Wong d22245a2e3 hashmap_entry_init takes "struct hashmap_entry *"
C compilers do type checking to make life easier for us.  So
rely on that and update all hashmap_entry_init callers to take
"struct hashmap_entry *" to avoid future bugs while improving
safety and readability.

Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-07 10:20:09 +09:00
Derrick Stolee 65edd96aec treewide: rename 'exclude' methods to 'pattern'
The first consumer of pattern-matching filenames was the
.gitignore feature. In that context, storing a list of patterns
as a 'struct exclude_list'  makes sense. However, the
sparse-checkout feature then adopted these structures and methods,
but with the opposite meaning: these patterns match the files
that should be included!

It would be clearer to rename this entire library as a "pattern
matching" library, and the callers apply exclusion/inclusion
logic accordingly based on their needs.

This commit renames several methods defined in dir.h to make
more sense with the renamed 'struct exclude_list' to 'struct
pattern_list' and 'struct exclude' to 'struct path_pattern':

 * last_exclude_matching() -> last_matching_pattern()
 * parse_exclude() -> parse_path_pattern()

In addition, the word 'exclude' was replaced with 'pattern'
in the methods below:

 * add_exclude_list()
 * add_excludes_from_file_to_list()
 * add_excludes_from_file()
 * add_excludes_from_blob_to_list()
 * add_exclude()
 * clear_exclude_list()

A few methods with the word "exclude" remain. These will
be handled seperately. In particular, the method
"is_excluded()" is concretely about the .gitignore file
relative to a specific directory. This is the important
boundary between library and consumer: is_excluded() cares
about .gitignore, but is_excluded() calls
last_matching_pattern() to make that decision.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-05 14:05:12 -07:00
Derrick Stolee 4ff89ee52c treewide: rename 'EXCL_FLAG_' to 'PATTERN_FLAG_'
The first consumer of pattern-matching filenames was the
.gitignore feature. In that context, storing a list of patterns
as a 'struct exclude_list'  makes sense. However, the
sparse-checkout feature then adopted these structures and methods,
but with the opposite meaning: these patterns match the files
that should be included!

It would be clearer to rename this entire library as a "pattern
matching" library, and the callers apply exclusion/inclusion
logic accordingly based on their needs.

This commit replaces 'EXCL_FLAG_' to 'PATTERN_FLAG_' in the
names of the flags used on 'struct path_pattern'.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-05 14:05:12 -07:00
Junio C Hamano 0f519aba51 Merge branch 'rd/attr.c-comment-typofix'
In-code comment typofix.

* rd/attr.c-comment-typofix:
  attr.c: ".gitattribute" -> ".gitattributes" (comments)
2019-03-11 16:16:24 +09:00
Robert P. J. Day bb101aaf0c attr.c: ".gitattribute" -> ".gitattributes" (comments)
Correct misspelled ".gitattribute" in comments only, so no functional
change.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-03-07 09:34:47 +09:00
Junio C Hamano 7589e63648 Merge branch 'nd/the-index-final'
The assumption to work on the single "in-core index" instance has
been reduced from the library-ish part of the codebase.

* nd/the-index-final:
  cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch
  read-cache.c: remove the_* from index_has_changes()
  merge-recursive.c: remove implicit dependency on the_repository
  merge-recursive.c: remove implicit dependency on the_index
  sha1-name.c: remove implicit dependency on the_index
  read-cache.c: replace update_index_if_able with repo_&
  read-cache.c: kill read_index()
  checkout: avoid the_index when possible
  repository.c: replace hold_locked_index() with repo_hold_locked_index()
  notes-utils.c: remove the_repository references
  grep: use grep_opt->repo instead of explict repo argument
2019-02-06 22:05:23 -08:00
Junio C Hamano 02bf766cc5 Merge branch 'jk/attr-macro-fix'
Asking "git check-attr" about a macro (e.g. "binary") on a specific
path did not work correctly, even though "git check-attr -a" listed
such a macro correctly.  This has been corrected.

* jk/attr-macro-fix:
  attr: do not mark queried macros as unset
2019-02-05 14:26:16 -08:00
Nguyễn Thái Ngọc Duy f8adbec9fe cache.h: flip NO_THE_INDEX_COMPATIBILITY_MACROS switch
By default, index compat macros are off from now on, because they
could hide the_index dependency.

Only those in builtin can use it.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-24 11:55:06 -08:00
Jeff King 7b95849be4 attr: do not mark queried macros as unset
Since 60a12722ac (attr: remove maybe-real, maybe-macro from git_attr,
2017-01-27), we will always mark an attribute macro (e.g., "binary")
that is specifically queried for as "unspecified", even though listing
_all_ attributes would display it at set. E.g.:

  $ echo "* binary" >.gitattributes

  $ git check-attr -a file
  file: binary: set
  file: diff: unset
  file: merge: unset
  file: text: unset

  $ git check-attr binary file
  file: binary: unspecified

The problem stems from an incorrect conversion of the optimization from
06a604e670 (attr: avoid heavy work when we know the specified attr is
not defined, 2014-12-28). There we tried in collect_some_attrs() to
avoid even looking at the attr_stack when the user has asked for "foo"
and we know that "foo" did not ever appear in any .gitattributes file.

It used a flag "maybe_real" in each attribute struct, where "real" meant
that the attribute appeared in an actual file (we have to make this
distinction because we also create an attribute struct for any names
that are being queried). But as explained in that commit message, the
meaning of "real" was tangled with some special cases around macros.

When 60a12722ac later refactored the macro code, it dropped maybe_real
entirely. This missed the fact that "maybe_real" could be unset for two
reasons: because of a macro, or because it was never found during
parsing. This had two results:

  - the optimization in collect_some_attrs() ceased doing anything
    meaningful, since it no longer kept track of "was it found during
    parsing"

  - worse, it actually kicked in when the caller _did_ ask about a macro
    by name, causing us to mark it as unspecified

It should be possible to salvage this optimization, but let's start with
just removing the remnants. It hasn't been doing anything (except
creating bugs) since 60a12722ac, and nobody seems to have noticed the
performance regression. It's more important to fix the correctness
problem clearly first.

I've added two tests here. The second one actually shows off the bug.
The test of "check-attr -a" is not strictly necessary, but we currently
do not test attribute macros much, and the builtin "binary" not at all.
So this increases our general test coverage, as well as making sure we
didn't mess up this related case.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-01-22 13:48:15 -08:00
Junio C Hamano 3813a89fae Merge branch 'nd/i18n'
More _("i18n") markings.

* nd/i18n:
  fsck: mark strings for translation
  fsck: reduce word legos to help i18n
  parse-options.c: mark more strings for translation
  parse-options.c: turn some die() to BUG()
  parse-options: replace opterror() with optname()
  repack: mark more strings for translation
  remote.c: mark messages for translation
  remote.c: turn some error() or die() to BUG()
  reflog: mark strings for translation
  read-cache.c: add missing colon separators
  read-cache.c: mark more strings for translation
  read-cache.c: turn die("internal error") to BUG()
  attr.c: mark more string for translation
  archive.c: mark more strings for translation
  alias.c: mark split_cmdline_strerror() strings for translation
  git.c: mark more strings for translation
2019-01-04 13:33:31 -08:00
Nguyễn Thái Ngọc Duy ad8f8f4aed attr.c: mark more string for translation
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-12 14:47:09 +09:00
Nguyễn Thái Ngọc Duy 2e1b141a01 attr.c: remove #ifdef NO_PTHREADS
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-05 13:42:11 +09:00
Torsten Bögershausen d64324cb60 Make git_check_attr() a void function
git_check_attr() returns always 0.
Remove all the error handling code of the callers, which is never executed.
Change git_check_attr() to be a void function.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-09-12 15:15:34 -07:00
Nguyễn Thái Ngọc Duy c4500e251f attr: remove index from git_attr_set_direction()
Since attr checking API now take the index, there's no need to set an
index in advance with this call. Most call sites are straightforward
because they either pass the_index or NULL (which defaults back to
the_index previously). There's only one suspicious call site in
unpack-trees.c where it sets a different index.

This code in unpack-trees is about to check out entries from the
new/temporary index after merging is done in it. The attributes will
be used by entry.c code to do crlf conversion if needed. entry.c now
respects struct checkout's istate field, and this field is correctly
set in unpack-trees.c, there should be no regression from this change.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 14:14:43 -07:00
Nguyễn Thái Ngọc Duy 7a400a2c02 attr: remove an implicit dependency on the_index
Make the attr API take an index_state instead of assuming the_index in
attr code. All call sites are converted blindly to keep the patch
simple and retain current behavior. Individual call sites may receive
further updates to use the right index instead of the_index.

There is one ugly temporary workaround added in attr.c that needs some
more explanation.

Commit c24f3abace (apply: file commited with CRLF should roundtrip
diff and apply - 2017-08-19) forces one convert_to_git() call to NOT
read the index at all. But what do you know, we read it anyway by
falling back to the_index. When "istate" from convert_to_git is now
propagated down to read_attr_from_array() we will hit segfault
somewhere inside read_blob_data_from_index.

The right way of dealing with this is to kill "use_index" variable and
only follow "istate" but at this stage we are not ready for that:
while most git_attr_set_direction() calls just passes the_index to be
assigned to use_index, unpack-trees passes a different one which is
used by entry.c code, which has no way to know what index to use if we
delete use_index. So this has to be done later.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-08-13 14:14:42 -07:00
Johannes Schindelin 033abf97fc Replace all die("BUG: ...") calls by BUG() ones
In d8193743e0 (usage.c: add BUG() function, 2017-05-12), a new macro
was introduced to use for reporting bugs instead of die(). It was then
subsequently used to convert one single caller in 588a538ae5
(setup_git_env: convert die("BUG") to BUG(), 2017-05-12).

The cover letter of the patch series containing this patch
(cf 20170513032414.mfrwabt4hovujde2@sigill.intra.peff.net) is not
terribly clear why only one call site was converted, or what the plan
is for other, similar calls to die() to report bugs.

Let's just convert all remaining ones in one fell swoop.

This trick was performed by this invocation:

	sed -i 's/die("BUG: /BUG("/g' $(git grep -l 'die("BUG' \*.c)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-06 19:06:13 +09:00
Stefan Beller d807c4a01d exec_cmd: rename to use dash in file name
This is more consistent with the project style. The majority of Git's
source files use dashes in preference to underscores in their file names.

Signed-off-by: Stefan Beller <sbeller@google.com>
2018-04-11 18:11:00 +09:00
Jeff Hostetler 8b604d1951 hashmap: add API to disable item counting when threaded
This is to address concerns raised by ThreadSanitizer on the mailing list
about threaded unprotected R/W access to map.size with my previous "disallow
rehash" change (0607e10009).

See:
https://public-inbox.org/git/adb37b70139fd1e2bac18bfd22c8b96683ae18eb.1502780344.git.martin.agren@gmail.com/

Add API to hashmap to disable item counting and thus automatic rehashing.
Also include API to later re-enable them.

When item counting is disabled, the map.size field is invalid.  So to
prevent accidents, the field has been renamed and an accessor function
hashmap_get_size() has been added.  All direct references to this
field have been been updated.  And the name of the field changed
to map.private_size to communicate this.

Here is the relevant output from ThreadSanitizer showing the problem:

WARNING: ThreadSanitizer: data race (pid=10554)
  Read of size 4 at 0x00000082d488 by thread T2 (mutexes: write M16):
    #0 hashmap_add hashmap.c:209
    #1 hash_dir_entry_with_parent_and_prefix name-hash.c:302
    #2 handle_range_dir name-hash.c:347
    #3 handle_range_1 name-hash.c:415
    #4 lazy_dir_thread_proc name-hash.c:471
    #5 <null> <null>

  Previous write of size 4 at 0x00000082d488 by thread T1 (mutexes: write M31):
    #0 hashmap_add hashmap.c:209
    #1 hash_dir_entry_with_parent_and_prefix name-hash.c:302
    #2 handle_range_dir name-hash.c:347
    #3 handle_range_1 name-hash.c:415
    #4 handle_range_dir name-hash.c:380
    #5 handle_range_1 name-hash.c:415
    #6 lazy_dir_thread_proc name-hash.c:471
    #7 <null> <null>

Martin gives instructions for running TSan on test t3008 in this post:
https://public-inbox.org/git/CAN0heSoJDL9pWELD6ciLTmWf-a=oyxe4EXXOmCKvsG5MSuzxsA@mail.gmail.com/

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-07 09:42:02 +09:00
Stefan Beller 201c14e375 attr.c: drop hashmap_cmp_fn cast
MAke the code more readable and less error prone by avoiding the cast
of the compare function pointer in hashmap_init, but instead have the
correctly named void pointers to casted to the specific data structure.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05 13:53:12 -07:00