* 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
...
While the only permitted drive letters for physical drives on Windows
are letters of the US-English alphabet, this restriction does not apply
to virtual drives assigned via `subst <letter>: <path>`.
To prevent targeted attacks against systems where "funny" drive letters
such as `1` or `!` are assigned, let's handle them as regular drive
letters on Windows.
This fixes CVE-2019-1351.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
Over a decade ago, in 25fe217b86 (Windows: Treat Windows style path
names., 2008-03-05), Git was taught to handle absolute Windows paths,
i.e. paths that start with a drive letter and a colon.
Unbeknownst to us, while drive letters of physical drives are limited to
letters of the English alphabet, there is a way to assign virtual drive
letters to arbitrary directories, via the `subst` command, which is
_not_ limited to English letters.
It is therefore possible to have absolute Windows paths of the form
`1:\what\the\hex.txt`. Even "better": pretty much arbitrary Unicode
letters can also be used, e.g. `ä:\tschibät.sch`.
While it can be sensibly argued that users who set up such funny drive
letters really seek adverse consequences, the Windows Operating System
is known to be a platform where many users are at the mercy of
administrators who have their very own idea of what constitutes a
reasonable setup.
Therefore, let's just make sure that such funny paths are still
considered absolute paths by Git, on Windows.
In addition to Unicode characters, pretty much any character is a valid
drive letter, as far as `subst` is concerned, even `:` and `"` or even a
space character. While it is probably the opposite of smart to use them,
let's safeguard `is_dos_drive_prefix()` against all of them.
Note: `[::1]:repo` is a valid URL, but not a valid path on Windows.
As `[` is now considered a valid drive letter, we need to be very
careful to avoid misinterpreting such a string as valid local path in
`url_is_local_not_ssh()`. To do that, we use the just-introduced
function `is_valid_path()` (which will label the string as invalid file
name because of the colon characters).
This fixes CVE-2019-1351.
Reported-by: Nicolas Joly <Nicolas.Joly@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
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>
Certain characters are not admissible in file names on Windows, even if
Cygwin/MSYS2 (and therefore, Git for Windows' Bash) pretend that they
are, e.g. `:`, `<`, `>`, etc
Let's disallow those characters explicitly in Windows builds of Git.
Note: just like trailing spaces or periods, it _is_ possible on Windows
to create commits adding files with such illegal characters, as long as
the operation leaves the worktree untouched. To allow for that, we
continue to guard `is_valid_win32_path()` behind the config setting
`core.protectNTFS`, so that users _can_ continue to do that, as long as
they turn the protections off via that config setting.
Among other problems, this prevents Git from trying to write to an "NTFS
Alternate Data Stream" (which refers to metadata stored alongside a
file, under a special name: "<filename>:<stream-name>"). This fix
therefore also prevents an attack vector that was exploited in
demonstrations of a number of recently-fixed security bugs.
Further reading on illegal characters in Win32 filenames:
https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
On Windows, file names cannot contain asterisks nor newline characters.
In an upcoming commit, we will make this limitation explicit,
disallowing even the creation of commits that introduce such file names.
However, in the test scripts touched by this patch, we _know_ that those
paths won't be checked out, so we _want_ to allow such file names.
Happily, the stringent path validation will be guarded via the
`core.protectNTFS` flag, so all we need to do is to force that flag off
temporarily.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
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>
We need to be careful to follow proper quoting rules. For example, if an
argument contains spaces, we have to quote them. Double-quotes need to
be escaped. Backslashes need to be escaped, but only if they are
followed by a double-quote character.
We need to be _extra_ careful to consider the case where an argument
ends in a backslash _and_ needs to be quoted: in this case, we append a
double-quote character, i.e. the backslash now has to be escaped!
The current code, however, fails to recognize that, and therefore can
turn an argument that ends in a single backslash into a quoted argument
that now ends in an escaped double-quote character. This allows
subsequent command-line parameters to be split and part of them being
mistaken for command-line options, e.g. through a maliciously-crafted
submodule URL during a recursive clone.
Technically, we would not need to quote _all_ arguments which end in a
backslash _unless_ the argument needs to be quoted anyway. For example,
`test\` would not need to be quoted, while `test \` would need to be.
To keep the code simple, however, and therefore easier to reason about
and ensure its correctness, we now _always_ quote an argument that ends
in a backslash.
This addresses CVE-2019-1350.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Currently it is technically possible to let a submodule's git
directory point right into the git dir of a sibling submodule.
Example: the git directories of two submodules with the names `hippo`
and `hippo/hooks` would be `.git/modules/hippo/` and
`.git/modules/hippo/hooks/`, respectively, but the latter is already
intended to house the former's hooks.
In most cases, this is just confusing, but there is also a (quite
contrived) attack vector where Git can be fooled into mistaking remote
content for file contents it wrote itself during a recursive clone.
Let's plug this bug.
To do so, we introduce the new function `validate_submodule_git_dir()`
which simply verifies that no git dir exists for any leading directories
of the submodule name (if there are any).
Note: this patch specifically continues to allow sibling modules names
of the form `core/lib`, `core/doc`, etc, as long as `core` is not a
submodule name.
This fixes CVE-2019-1387.
Reported-by: Nicolas Joly <Nicolas.Joly@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We just safe-guarded `.git` against NTFS Alternate Data Stream-related
attack vectors, and now it is time to do the same for `.gitmodules`.
Note: In the added regression test, we refrain from verifying all kinds
of variations between short names and NTFS Alternate Data Streams: as
the new code disallows _all_ Alternate Data Streams of `.gitmodules`, it
is enough to test one in order to know that all of them are guarded
against.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Probably inspired by HFS' resource streams, NTFS supports "Alternate
Data Streams": by appending `:<stream-name>` to the file name,
information in addition to the file contents can be written and read,
information that is copied together with the file (unless copied to a
non-NTFS location).
These Alternate Data Streams are typically used for things like marking
an executable as having just been downloaded from the internet (and
hence not necessarily being trustworthy).
In addition to a stream name, a stream type can be appended, like so:
`:<stream-name>:<stream-type>`. Unless specified, the default stream
type is `$DATA` for files and `$INDEX_ALLOCATION` for directories. In
other words, `.git::$INDEX_ALLOCATION` is a valid way to reference the
`.git` directory!
In our work in Git v2.2.1 to protect Git on NTFS drives under
`core.protectNTFS`, we focused exclusively on NTFS short names, unaware
of the fact that NTFS Alternate Data Streams offer a similar attack
vector.
Let's fix this.
Seeing as it is better to be safe than sorry, we simply disallow paths
referring to *any* NTFS Alternate Data Stream of `.git`, not just
`::$INDEX_ALLOCATION`. This also simplifies the implementation.
This closes CVE-2019-1352.
Further reading about NTFS Alternate Data Streams:
https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-fscc/c54dec26-1551-4d3a-a0ea-4fa40f848eb3
Reported-by: Nicolas Joly <Nicolas.Joly@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
The backslash character is not a valid part of a file name on Windows.
Hence it is dangerous to allow writing files that were unpacked from
tree objects, when the stored file name contains a backslash character:
it will be misinterpreted as directory separator.
This not only causes ambiguity when a tree contains a blob `a\b` and a
tree `a` that contains a blob `b`, but it also can be used as part of an
attack vector to side-step the careful protections against writing into
the `.git/` directory during a clone of a maliciously-crafted
repository.
Let's prevent that, addressing CVE-2019-1354.
Note: we guard against backslash characters in tree objects' file names
_only_ on Windows (because on other platforms, even on those where NTFS
volumes can be mounted, the backslash character is _not_ a directory
separator), and _only_ when `core.protectNTFS = true` (because users
might need to generate tree objects for other platforms, of course
without touching the worktree, e.g. using `git update-index
--cacheinfo`).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In addition to preventing `.git` from being tracked by Git, on Windows
we also have to prevent `git~1` from being tracked, as the default NTFS
short name (also known as the "8.3 filename") for the file name `.git`
is `git~1`, otherwise it would be possible for malicious repositories to
write directly into the `.git/` directory, e.g. a `post-checkout` hook
that would then be executed _during_ a recursive clone.
When we implemented appropriate protections in 2b4c6efc82 (read-cache:
optionally disallow NTFS .git variants, 2014-12-16), we had analyzed
carefully that the `.git` directory or file would be guaranteed to be
the first directory entry to be written. Otherwise it would be possible
e.g. for a file named `..git` to be assigned the short name `git~1` and
subsequently, the short name generated for `.git` would be `git~2`. Or
`git~3`. Or even `~9999999` (for a detailed explanation of the lengths
we have to go to protect `.gitmodules`, see the commit message of
e7cb0b4455 (is_ntfs_dotgit: match other .git files, 2018-05-11)).
However, by exploiting two issues (that will be addressed in a related
patch series close by), it is currently possible to clone a submodule
into a non-empty directory:
- On Windows, file names cannot end in a space or a period (for
historical reasons: the period separating the base name from the file
extension was not actually written to disk, and the base name/file
extension was space-padded to the full 8/3 characters, respectively).
Helpfully, when creating a directory under the name, say, `sub.`, that
trailing period is trimmed automatically and the actual name on disk
is `sub`.
This means that while Git thinks that the submodule names `sub` and
`sub.` are different, they both access `.git/modules/sub/`.
- While the backslash character is a valid file name character on Linux,
it is not so on Windows. As Git tries to be cross-platform, it
therefore allows backslash characters in the file names stored in tree
objects.
Which means that it is totally possible that a submodule `c` sits next
to a file `c\..git`, and on Windows, during recursive clone a file
called `..git` will be written into `c/`, of course _before_ the
submodule is cloned.
Note that the actual exploit is not quite as simple as having a
submodule `c` next to a file `c\..git`, as we have to make sure that the
directory `.git/modules/b` already exists when the submodule is checked
out, otherwise a different code path is taken in `module_clone()` that
does _not_ allow a non-empty submodule directory to exist already.
Even if we will address both issues nearby (the next commit will
disallow backslash characters in tree entries' file names on Windows,
and another patch will disallow creating directories/files with trailing
spaces or periods), it is a wise idea to defend in depth against this
sort of attack vector: when submodules are cloned recursively, we now
_require_ the directory to be empty, addressing CVE-2019-1349.
Note: the code path we patch is shared with the code path of `git
submodule update --init`, which must not expect, in general, that the
directory is empty. Hence we have to introduce the new option
`--force-init` and hand it all the way down from `git submodule` to the
actual `git submodule--helper` process that performs the initial clone.
Reported-by: Nicolas Joly <Nicolas.Joly@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
As with export-marks in the previous commit, import-marks can access the
filesystem. This is significantly less dangerous than export-marks
because it only involves reading from arbitrary paths, rather than
writing them. However, it could still be surprising and have security
implications (e.g., exfiltrating data from a service that accepts
fast-import streams).
Let's lump it (and its "if-exists" counterpart) in with export-marks,
and enable the in-stream version only if --allow-unsafe-features is set.
Signed-off-by: Jeff King <peff@peff.net>
The fast-import stream command "feature export-marks=<path>" lets the
stream write marks to an arbitrary path. This may be surprising if you
are running fast-import against an untrusted input (which otherwise
cannot do anything except update Git objects and refs).
Let's disallow the use of this feature by default, and provide a
command-line option to re-enable it (you can always just use the
command-line --export-marks as well, but the in-stream version provides
an easy way for exporters to control the process).
This is a backwards-incompatible change, since the default is flipping
to the new, safer behavior. However, since the main users of the
in-stream versions would be import/export-based remote helpers, and
since we trust remote helpers already (which are already running
arbitrary code), we'll pass the new option by default when reading a
remote helper's stream. This should minimize the impact.
Note that the implementation isn't totally simple, as we have to work
around the fact that fast-import doesn't parse its command-line options
until after it has read any "feature" lines from the stream. This is how
it lets command-line options override in-stream. But in our case, it's
important to parse the new --allow-unsafe-features first.
There are three options for resolving this:
1. Do a separate "early" pass over the options. This is easy for us to
do because there are no command-line options that allow the
"unstuck" form (so there's no chance of us mistaking an argument
for an option), though it does introduce a risk of incorrect
parsing later (e.g,. if we convert to parse-options).
2. Move the option parsing phase back to the start of the program, but
teach the stream-reading code never to override an existing value.
This is tricky, because stream "feature" lines override each other
(meaning we'd have to start tracking the source for every option).
3. Accept that we might parse a "feature export-marks" line that is
forbidden, as long we don't _act_ on it until after we've parsed
the command line options.
This would, in fact, work with the current code, but only because
the previous patch fixed the export-marks parser to avoid touching
the filesystem.
So while it works, it does carry risk of somebody getting it wrong
in the future in a rather subtle and unsafe way.
I've gone with option (1) here as simple, safe, and unlikely to cause
regressions.
This fixes CVE-2019-1348.
Signed-off-by: Jeff King <peff@peff.net>
When we parse the --export-marks option, we don't immediately open the
file, but we do create any leading directories. This can be especially
confusing when a command-line option overrides an in-stream one, in
which case we'd create the leading directory for the in-stream file,
even though we never actually write the file.
Let's instead create the directories just before opening the file, which
means we'll create only useful directories. Note that this could change
the handling of relative paths if we chdir() in between, but we don't
actually do so; the only permanent chdir is from setup_git_directory()
which runs before either code path (potentially we should take the
pre-setup dir into account to avoid surprising the user, but that's an
orthogonal change).
The test just adapts the existing "override" test to use paths with
leading directories. This checks both that the correct directory is
created (which worked before but was not tested), and that the
overridden one is not (our new fix here).
While we're here, let's also check the error result of
safe_create_leading_directories(). We'd presumably notice any failure
immediately after when we try to open the file itself, but we can give a
more specific error message in this case.
Signed-off-by: Jeff King <peff@peff.net>
Our tests confirm that providing two "import-marks" options in a
fast-import stream is an error. However, the invoked command would fail
even without covering this case, because the marks files themselves do
not actually exist. Let's create the files to make sure we fail for the
right reason (we actually do, because the option parsing happens before
we open anything, but this future-proofs our test).
Signed-off-by: Jeff King <peff@peff.net>
* maint-2.14:
Git 2.14.5
submodule-config: ban submodule paths that start with a dash
submodule-config: ban submodule urls that start with dash
submodule--helper: use "--" to signal end of clone options
We recently banned submodule urls that look like
command-line options. This is the matching change to ban
leading-dash paths.
As with the urls, this should not break any use cases that
currently work. Even with our "--" separator passed to
git-clone, git-submodule.sh gets confused. Without the code
portion of this patch, the clone of "-sub" added in t7417
would yield results like:
/path/to/git-submodule: 410: cd: Illegal option -s
/path/to/git-submodule: 417: cd: Illegal option -s
/path/to/git-submodule: 410: cd: Illegal option -s
/path/to/git-submodule: 417: cd: Illegal option -s
Fetched in submodule path '-sub', but it did not contain b56243f8f4eb91b2f1f8109452e659f14dd3fbe4. Direct fetching of that commit failed.
Moreover, naively adding such a submodule doesn't work:
$ git submodule add $url -sub
The following path is ignored by one of your .gitignore files:
-sub
even though there is no such ignore pattern (the test script
hacks around this with a well-placed "git mv").
Unlike leading-dash urls, though, it's possible that such a
path _could_ be useful if we eventually made it work. So
this commit should be seen not as recommending a particular
policy, but rather temporarily closing off a broken and
possibly dangerous code-path. We may revisit this decision
later.
There are two minor differences to the tests in t7416 (that
covered urls):
1. We don't have a "./-sub" escape hatch to make this
work, since the submodule code expects to be able to
match canonical index names to the path field (so you
are free to add submodule config with that path, but we
would never actually use it, since an index entry would
never start with "./").
2. After this patch, cloning actually succeeds. Since we
ignore the submodule.*.path value, we fail to find a
config stanza for our submodule at all, and simply
treat it as inactive. We still check for the "ignoring"
message.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit taught the submodule code to invoke our
"git clone $url $path" with a "--" separator so that we
aren't confused by urls or paths that start with dashes.
However, that's just one code path. It's not clear if there
are others, and it would be an easy mistake to add one in
the future. Moreover, even with the fix in the previous
commit, it's quite hard to actually do anything useful with
such an entry. Any url starting with a dash must fall into
one of three categories:
- it's meant as a file url, like "-path". But then any
clone is not going to have the matching path, since it's
by definition relative inside the newly created clone. If
you spell it as "./-path", the submodule code sees the
"/" and translates this to an absolute path, so it at
least works (assuming the receiver has the same
filesystem layout as you). But that trick does not apply
for a bare "-path".
- it's meant as an ssh url, like "-host:path". But this
already doesn't work, as we explicitly disallow ssh
hostnames that begin with a dash (to avoid option
injection against ssh).
- it's a remote-helper scheme, like "-scheme::data". This
_could_ work if the receiver bends over backwards and
creates a funny-named helper like "git-remote--scheme".
But normally there would not be any helper that matches.
Since such a url does not work today and is not likely to do
anything useful in the future, let's simply disallow them
entirely. That protects the existing "git clone" path (in a
belt-and-suspenders way), along with any others that might
exist.
Our tests cover two cases:
1. A file url with "./" continues to work, showing that
there's an escape hatch for people with truly silly
repo names.
2. A url starting with "-" is rejected.
Note that we expect case (2) to fail, but it would have done
so even without this commit, for the reasons given above.
So instead of just expecting failure, let's also check for
the magic word "ignoring" on stderr. That lets us know that
we failed for the right reason.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint-2.14:
Git 2.14.4
Git 2.13.7
verify_path: disallow symlinks in .gitmodules
update-index: stat updated files earlier
verify_dotfile: mention case-insensitivity in comment
verify_path: drop clever fallthrough
skip_prefix: add case-insensitive variant
is_{hfs,ntfs}_dotgitmodules: add tests
is_ntfs_dotgit: match other .git files
is_hfs_dotgit: match other .git files
is_ntfs_dotgit: use a size_t for traversing string
submodule-config: verify submodule names as paths
* maint-2.13:
Git 2.13.7
verify_path: disallow symlinks in .gitmodules
update-index: stat updated files earlier
verify_dotfile: mention case-insensitivity in comment
verify_path: drop clever fallthrough
skip_prefix: add case-insensitive variant
is_{hfs,ntfs}_dotgitmodules: add tests
is_ntfs_dotgit: match other .git files
is_hfs_dotgit: match other .git files
is_ntfs_dotgit: use a size_t for traversing string
submodule-config: verify submodule names as paths
This tests primarily for NTFS issues, but also adds one example of an
HFS+ issue.
Thanks go to Congyi Wu for coming up with the list of examples where
NTFS would possibly equate the filename with `.gitmodules`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff King <peff@peff.net>
Submodule "names" come from the untrusted .gitmodules file,
but we blindly append them to $GIT_DIR/modules to create our
on-disk repo paths. This means you can do bad things by
putting "../" into the name (among other things).
Let's sanity-check these names to avoid building a path that
can be exploited. There are two main decisions:
1. What should the allowed syntax be?
It's tempting to reuse verify_path(), since submodule
names typically come from in-repo paths. But there are
two reasons not to:
a. It's technically more strict than what we need, as
we really care only about breaking out of the
$GIT_DIR/modules/ hierarchy. E.g., having a
submodule named "foo/.git" isn't actually
dangerous, and it's possible that somebody has
manually given such a funny name.
b. Since we'll eventually use this checking logic in
fsck to prevent downstream repositories, it should
be consistent across platforms. Because
verify_path() relies on is_dir_sep(), it wouldn't
block "foo\..\bar" on a non-Windows machine.
2. Where should we enforce it? These days most of the
.gitmodules reads go through submodule-config.c, so
I've put it there in the reading step. That should
cover all of the C code.
We also construct the name for "git submodule add"
inside the git-submodule.sh script. This is probably
not a big deal for security since the name is coming
from the user anyway, but it would be polite to remind
them if the name they pick is invalid (and we need to
expose the name-checker to the shell anyway for our
test scripts).
This patch issues a warning when reading .gitmodules
and just ignores the related config entry completely.
This will generally end up producing a sensible error,
as it works the same as a .gitmodules file which is
missing a submodule entry (so "submodule update" will
barf, but "git clone --recurse-submodules" will print
an error but not abort the clone.
There is one minor oddity, which is that we print the
warning once per malformed config key (since that's how
the config subsystem gives us the entries). So in the
new test, for example, the user would see three
warnings. That's OK, since the intent is that this case
should never come up outside of malicious repositories
(and then it might even benefit the user to see the
message multiple times).
Credit for finding this vulnerability and the proof of
concept from which the test script was adapted goes to
Etienne Stalmans.
Signed-off-by: Jeff King <peff@peff.net>
A few scripts (both in production and tests) incorrectly redirected
their error output. These have been corrected.
* tz/redirect-fix:
rebase: fix stderr redirect in apply_autostash()
t/lib-gpg: fix gpgconf stderr redirect to /dev/null
"git notes" sent its error message to its standard output stream,
which was corrected.
* tz/notes-error-to-stderr:
notes: send "Automatic notes merge failed" messages to stderr
The three-way merge performed by "git cherry-pick" was confused
when a new submodule was added in the meantime, which has been
fixed (or "papered over").
* sb/test-cherry-pick-submodule-getting-in-a-way:
merge-recursive: handle addition of submodule on our side of history
t/3512: demonstrate unrelated submodule/file conflict as cherry-pick failure
"git apply --inaccurate-eof" when used with "--ignore-space-change"
triggered an internal sanity check, which has been fixed.
* rs/apply-inaccurate-eof-with-incomplete-line:
apply: update line lengths for --inaccurate-eof
When "git rebase" prepared an mailbox of changes and fed it to "git
am" to replay them, it was confused when a stray "From " happened
to be in the log message of one of the replayed changes. This has
been corrected.
* ew/rebase-mboxrd:
rebase: use mboxrd format to avoid split errors
Recent update to the refs infrastructure implementation started
rewriting packed-refs file more often than before; this has been
optimized again for most trivial cases.
* mh/avoid-rewriting-packed-refs:
files-backend: don't rewrite the `packed-refs` file unnecessarily
t1409: check that `packed-refs` is not rewritten unnecessarily
Replace the mailing address of FSF to a URL, as FSF prefers.
* tz/fsf-address-update:
Replace Free Software Foundation address in license notices
Replace Free Software Foundation address in license notices
Some error messages did not quote filenames shown in it, which have
been fixed.
* sr/wrapper-quote-filenames:
wrapper.c: consistently quote filenames in error messages
"git rebase -i" recently started misbehaving when a submodule that
is configured with 'submodule.<name>.ignore' is dirty; this has
been corrected.
* bw/rebase-i-ignored-submodule-fix:
wt-status: actually ignore submodules when requested
The mboxrd format allows the use of embedded "From " lines in
commit messages without being misinterpreted by mailsplit
Reported-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Eric Wong <e@80x24.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Some diff implementations don't report missing newlines at the end of
files. Applying such a patch can cause a newline character to be
added inadvertently. The option --inaccurate-eof of git apply can be
used to remove trailing newlines if needed.
apply_one_fragment() cuts it off from the buffers for preimage and
postimage. Before it does, it builds an array with the lengths of each
line for both. Make sure to update the length of the last line in
these line info structures as well to keep them consistent with their
respective buffer.
Without this fix the added test fails; git apply dies and reports:
fatal: BUG: caller miscounted postlen: asked 1, orig = 1, used = 2
That sanity check is only called if whitespace changes are ignored.
Reported-by: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code for a newly added path assumed that the path was a normal file,
and thus checked for there being a directory still being in the way of
the file. Note that since unpack_trees() does path-in-the-way checks
already, the only way for there to be a directory in the way at this
point in the code, is if there is some kind of D/F conflict in the merge.
For a submodule addition on HEAD's side of history, the submodule would
have already been present. This means that we do expect there to be a
directory present but should not consider it to be "in the way"; instead,
it's the expected submodule. So, when there's a submodule addition from
HEAD's side, don't bother checking the working copy for a directory in
the way.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
MinGW updates.
* js/mingw-redirect-std-handles:
mingw: document the standard handle redirection
mingw: optionally redirect stderr/stdout via the same handle
mingw: add experimental feature to redirect standard handles
"git check-ref-format --branch @{-1}" bit a "BUG()" when run
outside a repository for obvious reasons; clarify the documentation
and make sure we do not even try to expand the at-mark magic in
such a case, but still call the validation logic for branch names.
* jc/check-ref-format-oor:
check-ref-format doc: --branch validates and expands <branch>
check-ref-format --branch: strip refs/heads/ using skip_prefix
check-ref-format --branch: do not expand @{...} outside repository
A recent regression in "git rebase -i" that broke execution of git
commands from subdirectories via "exec" insn has been fixed.
* jk/rebase-i-exec-gitdir-fix:
sequencer: pass absolute GIT_DIR to exec commands
