There's a test in t5551 which checks the curl trace (after simplifying
it a bit). It doesn't work with HTTP/2, because in that case curl
outputs all of the headers in lower-case. Even though this test is run
with HTTP/2 by t5559, nobody has noticed because checking the trace only
happens if GIT_TEST_PROTOCOL_VERSION is manually set to "0".
Let's fix this by lower-casing all of the header names in the trace, and
then checking for those in our expected code (this is easier than making
HTTP/2 traces look like HTTP/1.1, since HTTP/1.1 uses title-casing).
Sadly, we can't quite do this in our existing sed script. This works if
you have GNU sed:
s/^\\([><]\\) \\([A-Za-z0-9-]*:\\)/\1 \L\2\E/
but \L is a GNU-ism, and I don't think there's a portable solution. We
could just "tr A-Z a-z" on the way in, of course, but that makes the
non-header parts harder to read (e.g., lowercase "post" requests). But
to paraphrase Baron Munchausen, I have learned from experience that a
modicum of Perl can be most efficacious.
Note that this doesn't quite get the test passing with t5559; there are
more fixes needed on top.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit b0c4adcdd7 (remote-curl: send Accept-Language header to server,
2022-07-11) added tests to make sure the header is sent via HTTP.
However, it checks in two places:
1. In the expected trace output, we check verbatim for the header and
its value.
2. Afterwards, we grep for the header again in the trace file.
This (2) is probably cargo-culted from the earlier grep for
Accept-Encoding. It is needed for the encoding because we smudge the
value of that header when doing the verbatim check; see 1a53e692af
(remote-curl: accept all encodings supported by curl, 2018-05-22).
But we don't do so for the language header, so any problem that the
"grep" would catch in (2) would already have been caught by (1).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Commit 9ee6bcd398 (t5541-http-push: add test for URLs with trailing
slash, 2010-04-08) added a test that clones a URL with a trailing slash,
and confirms that we don't send a doubled slash (like "$url//info/refs")
to the server.
But this test makes no sense in t5541, which is about pushing. It should
have been added in t5551. Let's move it there.
But putting it at the end is tricky, since it checks the entire contents
of the Apache access log. We could get around this by clearing the log
before our test. But there's an even simpler solution: just make sure no
doubled slashes appear in the log (fortunately, "http://" does not
appear in the log itself).
As a bonus, this also lets us drop the check for the v0 protocol (which
is otherwise necessary since v2 makes multiple requests, and
check_access_log insists on exactly matching the number of requests,
even though we don't care about that here).
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
We have a test which checks to see if a request to git-receive-pack was
made. Originally, it was checking the entire set of requests made in the
script so far, including clones, and thus it would break when run with
the v2 protocol (since that implies an extra request for fetches).
Since the previous commit, though, we are only checking the requests
made by a single push. And since there is no v2 push protocol, the test
now passes no matter what's in GIT_TEST_PROTOCOL_VERSION. We can just
run it all the time.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
There's a test in t5541 that confirms that "git push" makes two requests
(a GET to /info/refs, and a POST to /git-receive-pack). However, it's a
noop unless GIT_TEST_PROTOCOL_VERSION is set to "0", due to 8a1b0978ab
(test: request GIT_TEST_PROTOCOL_VERSION=0 when appropriate,
2019-12-23).
This means that almost nobody runs it. And indeed, it has been broken
since b0c4adcdd7 (remote-curl: send Accept-Language header to server,
2022-07-11). But the fault is not in that commit, but in how brittle the
test is. It runs after several operations have been performed, which
means that it expects to see the complete set of requests made so far in
the script. Commit b0c4adcdd7 added a new test, which means that the
"used receive-pack service" test must be updated, too.
Let's fix this by making the test less brittle. We'll move it higher in
the script, right after the first push has completed. And we'll clear
the access log right before doing the push, so we'll see only the
requests from that command.
This is technically testing less, in that we won't check that all of
those other requests also correctly used smart http. But there's no
particular reason think that if the first one did, the others wouldn't.
After this patch, running:
GIT_TEST_PROTOCOL_VERSION=0 ./t5541-http-push-smart.sh
passes, whereas it did not before.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git ls-tree --format='%(path) %(path)' $tree $path" showed the
path three times, which has been corrected.
* rs/ls-tree-path-expansion-fix:
ls-tree: remove dead store and strbuf for quote_c_style()
ls-tree: fix expansion of repeated %(path)
The logic to see if we are using the "cone" mode by checking the
sparsity patterns has been tightened to avoid mistaking a pattern
that names a single file as specifying a cone.
* ws/single-file-cone:
dir: check for single file cone patterns
"git diff --relative" did not mix well with "git diff --ext-diff",
which has been corrected.
* jk/ext-diff-with-relative:
diff: drop "name" parameter from prepare_temp_file()
diff: clean up external-diff argv setup
diff: use filespec path to set up tempfiles for ext-diff
Fix to a small regression in 2.38 days.
* ab/bundle-wo-args:
bundle <cmd>: have usage_msg_opt() note the missing "<file>"
builtin/bundle.c: remove superfluous "newargc" variable
bundle: don't segfault on "git bundle <subcmd>"
When given a pattern that matches an empty string at the end of a
line, the code to parse the "git diff" line-ranges fell into an
infinite loop, which has been corrected.
* lk/line-range-parsing-fix:
line-range: fix infinite loop bug with '$' regex
* maint-2.35:
Git 2.35.7
Git 2.34.7
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
Git 2.33.7
Git 2.32.6
Git 2.31.7
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
* maint-2.34:
Git 2.34.7
http: support CURLOPT_PROTOCOLS_STR
http: prefer CURLOPT_SEEKFUNCTION to CURLOPT_IOCTLFUNCTION
http-push: prefer CURLOPT_UPLOAD to CURLOPT_PUT
Git 2.33.7
Git 2.32.6
Git 2.31.7
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
* maint-2.33:
Git 2.33.7
Git 2.32.6
Git 2.31.7
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
* maint-2.32:
Git 2.32.6
Git 2.31.7
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
* maint-2.31:
Git 2.31.7
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
* maint-2.30:
Git 2.30.8
apply: fix writing behind newly created symbolic links
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
clone: delay picking a transport until after get_repo_path()
t5619: demonstrate clone_local() with ambiguous transport
Fix a vulnerability (CVE-2023-23946) that allows crafted input to trick
`git apply` into writing files outside of the working tree.
* ps/apply-beyond-symlink:
dir-iterator: prevent top-level symlinks without FOLLOW_SYMLINKS
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When writing files git-apply(1) initially makes sure that none of the
files it is about to create are behind a symlink:
```
$ git init repo
Initialized empty Git repository in /tmp/repo/.git/
$ cd repo/
$ ln -s dir symlink
$ git apply - <<EOF
diff --git a/symlink/file b/symlink/file
new file mode 100644
index 0000000..e69de29
EOF
error: affected file 'symlink/file' is beyond a symbolic link
```
This safety mechanism is crucial to ensure that we don't write outside
of the repository's working directory. It can be fooled though when the
patch that is being applied creates the symbolic link in the first
place, which can lead to writing files in arbitrary locations.
Fix this by checking whether the path we're about to create is
beyond a symlink or not. Tightening these checks like this should be
fine as we already have these precautions in Git as explained
above. Ideally, we should update the check we do up-front before
starting to reflect the computed changes to the working tree so that
we catch this case as well, but as part of embargoed security work,
adding an equivalent check just before we try to write out a file
should serve us well as a reasonable first step.
Digging back into history shows that this vulnerability has existed
since at least Git v2.9.0. As Git v2.8.0 and older don't build on my
system anymore I cannot tell whether older versions are affected, as
well.
Reported-by: Joern Schneeweisz <jschneeweisz@gitlab.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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>
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>
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>
expand_show_tree() borrows the base strbuf given to us by read_tree() to
build the full path of the current entry when handling %(path). Only
its indirect caller, show_tree_fmt(), removes the added entry name.
That works fine as long as %(path) is only included once in the format
string, but accumulates duplicates if it's repeated:
$ git ls-tree --format='%(path) %(path) %(path)' HEAD M*
Makefile MakefileMakefile MakefileMakefileMakefile
Reset the length after each use to get the same expansion every time;
here's the behavior with this patch:
$ ./git ls-tree --format='%(path) %(path) %(path)' HEAD M*
Makefile Makefile Makefile
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When we're going to run an external diff, we have to make the contents
of the pre- and post-images available either by dumping them to a
tempfile, or by pointing at a valid file in the worktree. The logic of
this is all handled by prepare_temp_file(), and we just pass in the
filename and the diff_filespec.
But there's a gotcha here. The "filename" we have is a logical filename
and not necessarily a path on disk or in the repository. This matters in
at least one case: when using "--relative", we may have a name like
"foo", even though the file content is found at "subdir/foo". As a
result, we look for the wrong path, fail to find "foo", and claim that
the file has been deleted (passing "/dev/null" to the external diff,
rather than the correct worktree path).
We can fix this by passing the pathname from the diff_filespec, which
should always be a full repository path (and that's what we want even if
reusing a worktree file, since we're always operating from the top-level
of the working tree).
The breakage seems to go all the way back to cd676a5136 (diff
--relative: output paths as relative to the current subdirectory,
2008-02-12). As far as I can tell, before then "name" would always have
been the same as the filespec's "path".
There are two related cases I looked at that aren't buggy:
1. the only other caller of prepare_temp_file() is run_textconv(). But
it always passes the filespec's path field, so it's OK.
2. I wondered if file renames/copies might cause similar confusion.
But they don't, because run_external_diff() receives two names in
that case: "name" and "other", which correspond to the two sides of
the diff. And we did correctly pass "other" when handling the
post-image side. Barring the use of "--relative", that would always
match "two->path", the path of the second filespec (and the rename
destination).
So the only bug is just the interaction with external diff drivers and
--relative.
Reported-by: Carl Baldwin <carl@ecbaldwin.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sparse checkout documentation states that the cone mode pattern set
is limited to patterns that either recursively include directories or
patterns that match all files in a directory. In the sparse checkout
file, the former manifest in the form:
/A/B/C/
while the latter become a pair of patterns either in the form:
/A/B/
!/A/B/*/
or in the special case of matching the toplevel files:
/*
!/*/
The 'add_pattern_to_hashsets()' function contains checks which serve to
disable cone-mode when non-cone patterns are encountered. However, these
do not catch when the pattern list attempts to match a single file or
directory, e.g. a pattern in the form:
/A/B/C
This causes sparse-checkout to exhibit unexpected behaviour when such a
pattern is in the sparse-checkout file and cone mode is enabled.
Concretely, with the pattern like the above, sparse-checkout, in
non-cone mode, will only include the directory or file located at
'/A/B/C'. However, with cone mode enabled, sparse-checkout will instead
just manifest the toplevel files but not any file located at '/A/B/C'.
Relatedly, issues occur when supplying the same kind of filter when
partial cloning with '--filter=sparse:oid=<oid>'. 'upload-pack' will
correctly just include the objects that match the non-cone pattern
matching. Which means that checking out the newly cloned repo with the
same filter, but with cone mode enabled, fails due to missing objects.
To fix these issues, add a cone mode pattern check that asserts that
every pattern is either a directory match or the pattern '/*'. Add a
test to verify the new pattern check and modify another to reflect that
non-directory patterns are caught earlier.
Signed-off-by: William Sprent <williams@unity3d.com>
Acked-by: Victoria Dye <vdye@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Since aef7d75e58 (builtin/bundle.c: let parse-options parse
subcommands, 2022-08-19) we've been segfaulting if no argument was
provided.
The fix is easy, as all of the "git bundle" subcommands require a
non-option argument we can check that we have arguments left after
calling parse-options().
This makes use of code added in 73c3253d75 (bundle: framework for
options before bundle file, 2019-11-10), before this change that code
has always been unreachable. In 73c3253d75 we'd never reach it as we
already checked "argc < 2" in cmd_bundle() itself.
Then when aef7d75e58 (whose segfault we're fixing here) migrated this
code to the subcommand API it removed that "argc < 2" check, but we
were still checking the wrong "argc" in parse_options_cmd_bundle(), we
need to check the "newargc". The "argc" will always be >= 1, as it
will necessarily contain at least the subcommand name
itself (e.g. "create").
As an aside, this could be safely squashed into this, but let's not do
that for this minimal segfault fix, as it's an unrelated refactoring:
--- a/builtin/bundle.c
+++ b/builtin/bundle.c
@@ -55,13 +55,12 @@ static int parse_options_cmd_bundle(int argc,
const char * const usagestr[],
const struct option options[],
char **bundle_file) {
- int newargc;
- newargc = parse_options(argc, argv, NULL, options, usagestr,
+ argc = parse_options(argc, argv, NULL, options, usagestr,
PARSE_OPT_STOP_AT_NON_OPTION);
- if (!newargc)
+ if (!argc)
usage_with_options(usagestr, options);
*bundle_file = prefix_filename(prefix, argv[0]);
- return newargc;
+ return argc;
}
static int cmd_bundle_create(int argc, const char **argv, const char *prefix) {
Reported-by: Hubert Jasudowicz <hubertj@stmcyber.pl>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Tested-by: Hubert Jasudowicz <hubertj@stmcyber.pl>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the -L argument to "git log" is passed the zero-width regular
expression "$" (as in "-L :$:line-range.c"), this results in an
infinite loop in find_funcname_matching_regexp().
Modify find_funcname_matching_regexp to correctly match the entire line
instead of the zero-width match at eol and update the loop condition to
prevent an infinite loop in the event of other undiscovered corner cases.
The primary change is that we pre-decrement the beginning-of-line marker
('bol') before comparing it to '\n'. In the case of '$', where we match the
'\n' at the end of the line and start the loop with bol == eol, this
ensures that bol will find the beginning of the line on which the match
occurred.
Originally reported in <https://stackoverflow.com/q/74690545/147356>.
Signed-off-by: Lars Kellogg-Stedman <lars@oddbit.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In b3b1a21d1a (sequencer: rewrite update-refs as user edits todo list,
2022-07-19), the 'todo_list_filter_update_refs()' step was added to handle
the removal of 'update-ref' lines from a 'rebase-todo'. Specifically, it
removes potential ref updates from the "update refs state" if a ref does not
have a corresponding 'update-ref' line.
However, because 'write_update_refs_state()' will not update the state if
the 'refs_to_oids' list was empty, removing *all* 'update-ref' lines will
result in the state remaining unchanged from how it was initialized (with
all refs' "after" OID being null). Then, when the ref update is applied, all
refs will be updated to null and consequently deleted.
To fix this, delete the 'update-refs' state file when 'refs_to_oids' is
empty. Additionally, add a tests covering "all update-ref lines removed"
cases.
Reported-by: herr.kaste <herr.kaste@gmail.com>
Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Helped-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Victoria Dye <vdye@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Recently, a vulnerability was reported that can lead to an out-of-bounds
write when reading an unreasonably large gitattributes file. The root
cause of this error are multiple integer overflows in different parts of
the code when there are either too many lines, when paths are too long,
when attribute names are too long, or when there are too many attributes
declared for a pattern.
As all of these are related to size, it seems reasonable to restrict the
size of the gitattributes file via git-fsck(1). This allows us to both
stop distributing known-vulnerable objects via common hosting platforms
that have fsck enabled, and users to protect themselves by enabling the
`fetch.fsckObjects` config.
There are basically two checks:
1. We verify that size of the gitattributes file is smaller than
100MB.
2. We verify that the maximum line length does not exceed 2048
bytes.
With the preceding commits, both of these conditions would cause us to
either ignore the complete gitattributes file or blob in the first case,
or the specific line in the second case. Now with these consistency
checks added, we also grow the ability to stop distributing such files
in the first place when `receive.fsckObjects` is enabled.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>