docs/git-pack-refs: document heuristic used for packing loose refs
The `git pack-refs --auto` flag asks the ref backend to decide for
itself whether or not references need to be repacked. This is done to
ensure that we don't repack in cases where the backend is already in a
good-enough state, which is typically the case for the "reftable"
backend that performs auto-compaction on writes.
As such, we initially only had heuristics in place for the "reftable"
backend. The "files" backend didn't have any heuristics, so we'd repack
loose references every time `git pack-refs --auto` was executed. This
caused excessive repacking with that backend though, which is why we
eventually implemented a heuristic via c3459ae9ef2 (refs/files: use
heuristic to decide whether to repack with `--auto`, 2024-09-04).
The documentation for the `--auto` flag hasn't been updated accordingly
and still claims that we don't have any metrics for the "files" backend.
Update it to reflect the new reality.
Reported-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Taylor Blau [Wed, 28 May 2025 18:59:31 +0000 (14:59 -0400)]
Sync with 2.46.4
* maint-2.46:
Git 2.46.4
Git 2.45.4
Git 2.44.4
Git 2.43.7
wincred: avoid buffer overflow in wcsncat()
bundle-uri: fix arbitrary file writes via parameter injection
config: quote values containing CR character
git-gui: sanitize 'exec' arguments: convert new 'cygpath' calls
git-gui: do not mistake command arguments as redirection operators
git-gui: introduce function git_redir for git calls with redirections
git-gui: pass redirections as separate argument to git_read
git-gui: pass redirections as separate argument to _open_stdout_stderr
git-gui: convert git_read*, git_write to be non-variadic
git-gui: override exec and open only on Windows
gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
git-gui: use git_read in githook_read
git-gui: sanitize $PATH on all platforms
git-gui: break out a separate function git_read_nice
git-gui: assure PATH has only absolute elements.
git-gui: remove option --stderr from git_read
git-gui: cleanup git-bash menu item
git-gui: sanitize 'exec' arguments: background
git-gui: avoid auto_execok in do_windows_shortcut
git-gui: sanitize 'exec' arguments: simple cases
git-gui: avoid auto_execok for git-bash menu item
git-gui: treat file names beginning with "|" as relative paths
git-gui: remove unused proc is_shellscript
git-gui: remove git config --list handling for git < 1.5.3
git-gui: remove special treatment of Windows from open_cmd_pipe
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui: use only the configured shell
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
git-gui: make _shellpath usable on startup
git-gui: use [is_Windows], not bad _shellpath
git-gui: _which, only add .exe suffix if not present
gitk: encode arguments correctly with "open"
gitk: sanitize 'open' arguments: command pipeline
gitk: collect construction of blameargs into a single conditional
gitk: sanitize 'open' arguments: simple commands, readable and writable
gitk: sanitize 'open' arguments: simple commands with redirections
gitk: sanitize 'open' arguments: simple commands
gitk: sanitize 'exec' arguments: redirect to process
gitk: sanitize 'exec' arguments: redirections and background
gitk: sanitize 'exec' arguments: redirections
gitk: sanitize 'exec' arguments: 'eval exec'
gitk: sanitize 'exec' arguments: simple cases
gitk: have callers of diffcmd supply pipe symbol when necessary
gitk: treat file names beginning with "|" as relative paths
Taylor Blau [Wed, 28 May 2025 18:57:08 +0000 (14:57 -0400)]
Sync with 2.45.4
* maint-2.45:
Git 2.45.4
Git 2.44.4
Git 2.43.7
wincred: avoid buffer overflow in wcsncat()
bundle-uri: fix arbitrary file writes via parameter injection
config: quote values containing CR character
git-gui: sanitize 'exec' arguments: convert new 'cygpath' calls
git-gui: do not mistake command arguments as redirection operators
git-gui: introduce function git_redir for git calls with redirections
git-gui: pass redirections as separate argument to git_read
git-gui: pass redirections as separate argument to _open_stdout_stderr
git-gui: convert git_read*, git_write to be non-variadic
git-gui: override exec and open only on Windows
gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
git-gui: use git_read in githook_read
git-gui: sanitize $PATH on all platforms
git-gui: break out a separate function git_read_nice
git-gui: assure PATH has only absolute elements.
git-gui: remove option --stderr from git_read
git-gui: cleanup git-bash menu item
git-gui: sanitize 'exec' arguments: background
git-gui: avoid auto_execok in do_windows_shortcut
git-gui: sanitize 'exec' arguments: simple cases
git-gui: avoid auto_execok for git-bash menu item
git-gui: treat file names beginning with "|" as relative paths
git-gui: remove unused proc is_shellscript
git-gui: remove git config --list handling for git < 1.5.3
git-gui: remove special treatment of Windows from open_cmd_pipe
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui: use only the configured shell
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
git-gui: make _shellpath usable on startup
git-gui: use [is_Windows], not bad _shellpath
git-gui: _which, only add .exe suffix if not present
gitk: encode arguments correctly with "open"
gitk: sanitize 'open' arguments: command pipeline
gitk: collect construction of blameargs into a single conditional
gitk: sanitize 'open' arguments: simple commands, readable and writable
gitk: sanitize 'open' arguments: simple commands with redirections
gitk: sanitize 'open' arguments: simple commands
gitk: sanitize 'exec' arguments: redirect to process
gitk: sanitize 'exec' arguments: redirections and background
gitk: sanitize 'exec' arguments: redirections
gitk: sanitize 'exec' arguments: 'eval exec'
gitk: sanitize 'exec' arguments: simple cases
gitk: have callers of diffcmd supply pipe symbol when necessary
gitk: treat file names beginning with "|" as relative paths
Taylor Blau [Wed, 28 May 2025 18:51:38 +0000 (14:51 -0400)]
Sync with 2.44.4
* maint-2.44:
Git 2.44.4
Git 2.43.7
wincred: avoid buffer overflow in wcsncat()
bundle-uri: fix arbitrary file writes via parameter injection
config: quote values containing CR character
git-gui: sanitize 'exec' arguments: convert new 'cygpath' calls
git-gui: do not mistake command arguments as redirection operators
git-gui: introduce function git_redir for git calls with redirections
git-gui: pass redirections as separate argument to git_read
git-gui: pass redirections as separate argument to _open_stdout_stderr
git-gui: convert git_read*, git_write to be non-variadic
git-gui: override exec and open only on Windows
gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
git-gui: use git_read in githook_read
git-gui: sanitize $PATH on all platforms
git-gui: break out a separate function git_read_nice
git-gui: assure PATH has only absolute elements.
git-gui: remove option --stderr from git_read
git-gui: cleanup git-bash menu item
git-gui: sanitize 'exec' arguments: background
git-gui: avoid auto_execok in do_windows_shortcut
git-gui: sanitize 'exec' arguments: simple cases
git-gui: avoid auto_execok for git-bash menu item
git-gui: treat file names beginning with "|" as relative paths
git-gui: remove unused proc is_shellscript
git-gui: remove git config --list handling for git < 1.5.3
git-gui: remove special treatment of Windows from open_cmd_pipe
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui: use only the configured shell
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
git-gui: make _shellpath usable on startup
git-gui: use [is_Windows], not bad _shellpath
git-gui: _which, only add .exe suffix if not present
gitk: encode arguments correctly with "open"
gitk: sanitize 'open' arguments: command pipeline
gitk: collect construction of blameargs into a single conditional
gitk: sanitize 'open' arguments: simple commands, readable and writable
gitk: sanitize 'open' arguments: simple commands with redirections
gitk: sanitize 'open' arguments: simple commands
gitk: sanitize 'exec' arguments: redirect to process
gitk: sanitize 'exec' arguments: redirections and background
gitk: sanitize 'exec' arguments: redirections
gitk: sanitize 'exec' arguments: 'eval exec'
gitk: sanitize 'exec' arguments: simple cases
gitk: have callers of diffcmd supply pipe symbol when necessary
gitk: treat file names beginning with "|" as relative paths
Taylor Blau [Wed, 28 May 2025 18:47:12 +0000 (14:47 -0400)]
Sync with 2.43.7
* maint-2.43:
Git 2.43.7
wincred: avoid buffer overflow in wcsncat()
bundle-uri: fix arbitrary file writes via parameter injection
config: quote values containing CR character
git-gui: sanitize 'exec' arguments: convert new 'cygpath' calls
git-gui: do not mistake command arguments as redirection operators
git-gui: introduce function git_redir for git calls with redirections
git-gui: pass redirections as separate argument to git_read
git-gui: pass redirections as separate argument to _open_stdout_stderr
git-gui: convert git_read*, git_write to be non-variadic
git-gui: override exec and open only on Windows
gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
git-gui: use git_read in githook_read
git-gui: sanitize $PATH on all platforms
git-gui: break out a separate function git_read_nice
git-gui: assure PATH has only absolute elements.
git-gui: remove option --stderr from git_read
git-gui: cleanup git-bash menu item
git-gui: sanitize 'exec' arguments: background
git-gui: avoid auto_execok in do_windows_shortcut
git-gui: sanitize 'exec' arguments: simple cases
git-gui: avoid auto_execok for git-bash menu item
git-gui: treat file names beginning with "|" as relative paths
git-gui: remove unused proc is_shellscript
git-gui: remove git config --list handling for git < 1.5.3
git-gui: remove special treatment of Windows from open_cmd_pipe
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui: use only the configured shell
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
git-gui: make _shellpath usable on startup
git-gui: use [is_Windows], not bad _shellpath
git-gui: _which, only add .exe suffix if not present
gitk: encode arguments correctly with "open"
gitk: sanitize 'open' arguments: command pipeline
gitk: collect construction of blameargs into a single conditional
gitk: sanitize 'open' arguments: simple commands, readable and writable
gitk: sanitize 'open' arguments: simple commands with redirections
gitk: sanitize 'open' arguments: simple commands
gitk: sanitize 'exec' arguments: redirect to process
gitk: sanitize 'exec' arguments: redirections and background
gitk: sanitize 'exec' arguments: redirections
gitk: sanitize 'exec' arguments: 'eval exec'
gitk: sanitize 'exec' arguments: simple cases
gitk: have callers of diffcmd supply pipe symbol when necessary
gitk: treat file names beginning with "|" as relative paths
Taylor Blau [Mon, 19 May 2025 22:30:29 +0000 (18:30 -0400)]
wincred: avoid buffer overflow in wcsncat()
The wincred credential helper uses a static buffer ("target") as a
unique key for storing and comparing against internal storage. It does
this by building up a string is supposed to look like:
git:$PROTOCOL://$USERNAME@$HOST/@PATH
However, the static "target" buffer is declared as a wide string with no
more than 1,024 wide characters. The first call to wcsncat() is almost
correct (it copies no more than ARRAY_SIZE(target) wchar_t's), but does
not account for the trailing NUL, introducing an off-by-one error.
But subsequent calls to wcsncat() have an additional problem on top of
the off-by-one. They do not account for the length of the existing
wide string being built up in 'target'. So the following:
$ perl -e '
my $x = "x" x 1_000;
print "protocol=$x\nhost=$x\nusername=$x\npath=$x\n"
' |
C\:/Program\ Files/Git/mingw64/libexec/git-core/git-credential-wincred.exe get
will result in a segmentation fault from over-filling buffer.
This bug is as old as the wincred helper itself, dating back to a6253da0f3 (contrib: add win32 credential-helper, 2012-07-27). Commit 8b2d219a3d (wincred: improve compatibility with windows versions,
2013-01-10) replaced the use of strncat() with wcsncat(), but retained
the buggy behavior.
Fix this by using a "target_append()" helper which accounts for both the
length of the existing string within the buffer, as well as the trailing
NUL character.
Reported-by: David Leadbeater <dgl@dgl.cx> Helped-by: David Leadbeater <dgl@dgl.cx> Helped-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Taylor Blau [Fri, 23 May 2025 21:17:06 +0000 (17:17 -0400)]
Merge branch 'js/gitk-git-gui-harden-exec-open' into maint-2.43
This merges in fixes for CVE-2025-27614, CVE-2025-27613, CVE-2025-46334,
and CVE-2025-46835 targeting Gitk and Git GUI.
* js/gitk-git-gui-harden-exec-open: (41 commits)
git-gui: sanitize 'exec' arguments: convert new 'cygpath' calls
git-gui: do not mistake command arguments as redirection operators
git-gui: introduce function git_redir for git calls with redirections
git-gui: pass redirections as separate argument to git_read
git-gui: pass redirections as separate argument to _open_stdout_stderr
git-gui: convert git_read*, git_write to be non-variadic
git-gui: override exec and open only on Windows
gitk: sanitize 'open' arguments: revisit recently updated 'open' calls
git-gui: use git_read in githook_read
git-gui: sanitize $PATH on all platforms
git-gui: break out a separate function git_read_nice
git-gui: assure PATH has only absolute elements.
git-gui: remove option --stderr from git_read
git-gui: cleanup git-bash menu item
git-gui: sanitize 'exec' arguments: background
git-gui: avoid auto_execok in do_windows_shortcut
git-gui: sanitize 'exec' arguments: simple cases
git-gui: avoid auto_execok for git-bash menu item
git-gui: treat file names beginning with "|" as relative paths
git-gui: remove unused proc is_shellscript
git-gui: remove git config --list handling for git < 1.5.3
git-gui: remove special treatment of Windows from open_cmd_pipe
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui: use only the configured shell
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
git-gui: make _shellpath usable on startup
git-gui: use [is_Windows], not bad _shellpath
git-gui: _which, only add .exe suffix if not present
gitk: encode arguments correctly with "open"
gitk: sanitize 'open' arguments: command pipeline
gitk: collect construction of blameargs into a single conditional
gitk: sanitize 'open' arguments: simple commands, readable and writable
gitk: sanitize 'open' arguments: simple commands with redirections
gitk: sanitize 'open' arguments: simple commands
gitk: sanitize 'exec' arguments: redirect to process
gitk: sanitize 'exec' arguments: redirections and background
gitk: sanitize 'exec' arguments: redirections
gitk: sanitize 'exec' arguments: 'eval exec'
gitk: sanitize 'exec' arguments: simple cases
gitk: have callers of diffcmd supply pipe symbol when necessary
gitk: treat file names beginning with "|" as relative paths
...
bundle-uri: fix arbitrary file writes via parameter injection
We fetch bundle URIs via `download_https_uri_to_file()`. The logic to
fetch those bundles is not handled in-process, but we instead use a
separate git-remote-https(1) process that performs the fetch for us. The
information about which file should be downloaded and where that file
should be put gets communicated via stdin of that process via a "get"
request. This "get" request has the form "get $uri $file\n\n". As may be
obvious to the reader, this will cause git-remote-https(1) to download
the URI "$uri" and put it into "$file".
The fact that we are using plain spaces and newlines as separators for
the request arguments means that we have to be extra careful with the
respective vaules of these arguments:
- If "$uri" contained a space we would interpret this as both URI and
target location.
- If either "$uri" or "$file" contained a newline we would interpret
this as a new command.
But we neither quote the arguments such that any characters with special
meaning would be escaped, nor do we verify that none of these special
characters are contained.
If either the URI or file contains a newline character, we are open to
protocol injection attacks. Likewise, if the URI itself contains a
space, then an attacker-controlled URI can lead to partially-controlled
file writes.
Note that the attacker-controlled URIs do not permit completely
arbitrary file writes, but instead allows an attacker to control the
path in which we will write a temporary (e.g., "tmp_uri_XXXXXX")
file.
The result is twofold:
- By adding a space in "$uri" we can control where exactly a file will
be written to, including out-of-repository writes. The final
location is not completely arbitrary, as the injected string will be
concatenated with the original "$file" path. Furthermore, the name
of the bundle will be "tmp_uri_XXXXXX", further restricting what an
adversary would be able to write.
Also note that is not possible for the URI to contain a newline
because we end up in `credential_from_url_1()` before we try to
issue any requests using that URI. As such, it is not possible to
inject arbitrary commands via the URI.
- By adding a newline to "$file" we can inject arbitrary commands.
This gives us full control over where a specific file will be
written to. Potential attack vectors would be to overwrite hooks,
but if an adversary were to guess where the user's home directory is
located they might also easily write e.g. a "~/.profile" file and
thus cause arbitrary code execution.
This injection can only become possible when the adversary has full
control over the target path where a bundle will be downloaded to.
While this feels unlikely, it is possible to control this path when
users perform a recursive clone with a ".gitmodules" file that is
controlled by the adversary.
Luckily though, the use of bundle URIs is not enabled by default in Git
clients (yet): they have to be enabled by setting the `bundle.heuristic`
config key explicitly. As such, the blast radius of this parameter
injection should overall be quite contained.
Fix the issue by rejecting spaces in the URI and newlines in both the
URI and the file. As explained, it shouldn't be required to also
restrict the use of newlines in the URI, as we would eventually die
anyway in `credential_from_url_1()`. But given that we're only one small
step away from arbitrary code execution, let's rather be safe and
restrict newlines in URIs, as well.
Eventually we should probably refactor the way that Git talks with the
git-remote-https(1) subprocess so that it is less fragile. Until then,
these two restrictions should plug the issue.
Reported-by: David Leadbeater <dgl@dgl.cx> Based-on-patch-by: David Leadbeater <dgl@dgl.cx> Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Justin Tobler [Tue, 20 May 2025 02:26:04 +0000 (21:26 -0500)]
config: quote values containing CR character
When reading the config, values that contain a trailing CRLF are
stripped. If the value itself has a trailing CR, the normal LF that
follows results in the CR being unintentionally stripped. This may lead
to unintended behavior due to the config value written being different
when it gets read.
One such issue involves a repository with a submodule path containing a
trailing CR. When the submodule gets initialized, the submodule is
cloned without being checked out and has "core.worktree" set to the
submodule path. The git-checkout(1) that gets spawned later reads the
"core.worktree" config value, but without the trailing CR, and
consequently attempts to checkout to a different path than intended.
If the repository contains a matching path that is a symlink, it is
possible for the submodule repository to be checked out in arbitrary
locations. This is extra bad when the symlink points to the submodule
hooks directory and the submodule repository contains an executable
"post-checkout" hook. Once the submodule repository checkout completes,
the "post-checkout" hook immediately executes.
To prevent mismatched config state due to misinterpreting a trailing CR,
wrap config values containing CR in double quotes when writing the
entry. This ensures a trailing CR is always separated for an LF and thus
prevented from getting stripped.
Note that this problem cannot be addressed by just quoting each CR with
"\r". The reading side of the config interprets only a few backslash
escapes, and "\r" is not among them. This fix is sufficient though
because it only affects the CR at the end of a line and any literal CR
in the interior is already preserved.
Co-authored-by: David Leadbeater <dgl@dgl.cx> Signed-off-by: Justin Tobler <jltobler@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Tue, 20 May 2025 06:56:09 +0000 (08:56 +0200)]
Merge branch 'js/fix-open-exec'
This addresses CVE-2025-46835, Git GUI can create and overwrite a
user's files:
When a user clones an untrusted repository and is tricked into editing
a file located in a maliciously named directory in the repository, then
Git GUI can create and overwrite files for which the user has write
permission.
Johannes Sixt [Tue, 20 May 2025 06:54:24 +0000 (08:54 +0200)]
Merge branch 'ml/replace-auto-execok'
This addresses CVE-2025-46334, Git GUI malicious command injection on
Windows.
A malicious repository can ship versions of sh.exe or typical textconv
filter programs such as astextplain. Due to the unfortunate design of
Tcl on Windows, the search path when looking for an executable always
includes the current directory. The mentioned programs are invoked when
the user selects "Git Bash" or "Browse Files" from the menu.
Johannes Sixt [Wed, 14 May 2025 17:56:27 +0000 (19:56 +0200)]
Merge branch 'js/fix-open-exec'
This addresses CVE-2025-27613, Gitk can create and truncate a user's
files:
When a user clones an untrusted repository and runs gitk without
additional command arguments, files for which the user has write
permission can be created and truncated. The option "Support per-file
encoding" must have been enabled before in Gitk's Preferences. This
option is disabled by default.
The same happens when "Show origin of this line" is used in the main
window (regardless of whether "Support per-file encoding" is enabled or
not).
Johannes Sixt [Wed, 14 May 2025 16:27:05 +0000 (18:27 +0200)]
Merge branch 'ah/fix-open-with-stdin'
This addresses CVE-2025-27614, Arbitrary command execution with Gitk:
A Git repository can be crafted in such a way that with some social
engineering a user who has cloned the repository can be tricked into
running any script (e.g., Bourne shell, Perl, Python, ...) supplied by
the attacker by invoking `gitk filename`, where `filename` has a
particular structure. The script is run with the privileges of the user.
Johannes Sixt [Sun, 4 May 2025 19:59:19 +0000 (21:59 +0200)]
git-gui: do not mistake command arguments as redirection operators
Tcl 'open' assigns special meaning to its argument when they begin with
redirection, pipe or background operator. There are many calls of the
'open' variant that runs a process which construct arguments that are
taken from the Git repository or are user input. However, when file
names or ref names are taken from the repository, it is possible to
find names that have these special forms. They must not be interpreted
by 'open' lest it redirects input or output, or attempts to build a
pipeline using a command name controlled by the repository.
Use the helper function make_arglist_safe, which identifies such
arguments and prepends "./" to force such a name to be regarded as a
relative file name.
After this change the following 'open' calls that start a process do not
apply the argument processing:
In all cases, the command arguments are constant strings (or begin with
a constant string) that are of a form that would not be affected by the
processing anyway.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sun, 4 May 2025 18:26:11 +0000 (20:26 +0200)]
git-gui: introduce function git_redir for git calls with redirections
Proc git invokes git and collects all output, which is it returns.
We are going to treat command arguments and redirections differently to
avoid passing arguments that look like redirections to the command
accidentally. A few invocations also pass redirection operators as
command arguments deliberately. Rewrite these cases to use a new
function git_redir that takes two lists, one for the regular command
arguments and one for the redirection operations.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sun, 4 May 2025 13:39:03 +0000 (15:39 +0200)]
git-gui: pass redirections as separate argument to git_read
We are going to treat command arguments and redirections differently to
avoid passing arguments that look like redirections to the command
accidentally. To do so, it will be necessary to know which arguments
are intentional redirections. Rewrite direct call sites of git_read
to pass intentional redirections as a second (optional) argument.
git_read defers to safe_open_command, but we cannot make it safe, yet,
because one of the callers of git_read is proc git, which does not yet
know which of its arguments are redirections. This is the topic of the
next commit.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sun, 4 May 2025 13:06:11 +0000 (15:06 +0200)]
git-gui: pass redirections as separate argument to _open_stdout_stderr
We are going to treat command arguments and redirections differently to
avoid passing arguments that look like redirections to the command
accidentally. To do so, it will be necessary to know which arguments
are intentional redirections. Rewrite direct callers of
_open_stdout_stderr to pass intentional redirections as a second
(optional) argument.
Passing arbitrary arguments is not safe right now, but we rename it
to safe_open_command anyway to avoid having to touch the call sites
again later when we make it actually safe.
We cannot make the function safe right away because one caller is
git_read, which does not yet know which of its arguments are
redirections. This is the topic of the next commit.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 3 May 2025 11:24:48 +0000 (13:24 +0200)]
git-gui: convert git_read*, git_write to be non-variadic
We are going to treat command arguments and redirections differently to
avoid passing arguments that look like redirections to the command
accidentally. To do so, it will be necessary to know which arguments
are intentional redirections. As a preparation, convert git_read,
git_read_nice, and git_write to take just a single argument that is
the command in a list. Adjust all call sites accordingly.
In the future, this argument will be the regular command arguments and
a second argument will be the redirection operations.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Fri, 11 Apr 2025 14:58:20 +0000 (10:58 -0400)]
git-gui: override exec and open only on Windows
Since aae9560a355d (Work around Tcl's default `PATH` lookup,
2022-11-23), git-gui overrides exec and open on all platforms. But,
this was done in response to Tcl adding elements to $PATH on Windows,
while exec, open, and auto_execok honor $PATH as given on all other
platforms.
Let's do the override only on Windows, restoring others to using their
native exec and open. These honor the sanitized $PATH as that is written
out to env(PATH) in a previous commit. auto_execok is also safe on these
platforms, so can be used for _which.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
The previous commits bb5cb23daf75 (gitk: prevent overly long command
lines, 2023-01-24) rewrote a set of the 'open' calls substantially.
These were then later updated by 7dd272eca153 (gitk: escape file paths
before piping to git log, 2023-01-24) and d5d1b91e5327 (gitk: encode
arguments correctly with "open", 2025-03-07). In the preceding merge,
the conversions to a safe_open variant were undone to ensure that the
principal operation of the new 'open' calls is not modified by accident.
Since the 'open' calls now pass a redirection from a Tcl string as
stdin, convert the calls to 'safe_open_command_redirect'.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 3 May 2025 17:21:53 +0000 (19:21 +0200)]
git-gui: use git_read in githook_read
0730a5a3a5e6 ("git-gui - use git-hook, honor core.hooksPath", 2023-09-17)
rewrote githook_read to use `git hook` to run a hook script. The code
that was replaced discovered the hook script file manually and invoked
it using function _open_stdout_stderr. After the rewrite, this function
is still invoked, but it calls into `git` instead of the hook scripts.
Notice though, that we have function git_read that invokes git and
prepares a pipe for the caller to read from. Replace the implementation
of githook_read to be just a wrapper around git_read. This unifies the
way in which the git executable is invoked. git_read ultimately also
calls into _open_stdout_stderr, but it modifies the path to the git
executable before doing so.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Fri, 11 Apr 2025 14:47:04 +0000 (10:47 -0400)]
git-gui: sanitize $PATH on all platforms
Since 8f23432b38d9 (windows: ignore empty `PATH` elements, 2022-11-23),
git-gui removes empty elements from $PATH, and a prior commit made this
remove all non-absolute elements from $PATH. But, this happens only on
Windows. Unsafe $PATH elements in $PATH are possible on all platforms.
Let's sanitize $PATH on all platforms to have consistent behavior. If a
user really wants the current repository on $PATH, they can add its
absolute name to $PATH.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 3 May 2025 11:11:21 +0000 (13:11 +0200)]
git-gui: break out a separate function git_read_nice
There are two callers of git_read that request special treatment using
option --nice. Rewrite them to call a new function git_read_nice that
does the special treatment. Now we can remove all option treatment from
git_read.
git_write has the same capability, but there are no callers that
request --nice. Remove the feature without substitution.
This is a preparation for a later change where we want to make git_read
and friends non-variadic. Then it cannot have optional arguments.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Fri, 11 Apr 2025 14:08:52 +0000 (10:08 -0400)]
git-gui: assure PATH has only absolute elements.
Since 8f23432b38d9 (windows: ignore empty `PATH` elements, 2022-11-23),
git-gui excises all empty paths from $PATH, but still allows '.' or
other relative paths, which can also allow executing code from the
repository. Let's remove anything except absolute elements. While here,
let's remove duplicated elements, which are very common on Windows:
only the first such item can do anything except waste time repeating a
search.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 3 May 2025 09:52:35 +0000 (11:52 +0200)]
git-gui: remove option --stderr from git_read
Some callers of git_read want to redirect stderr of the invoked command
to stdout. The function offers option --stderr for this purpose.
However, the option only appends 2>@1 to the commands. The callers can
do that themselves. In lib/console.tcl we even have a caller that
already knew implictly what --stderr does behind the scenes.
This is a preparation for a later change where we want to make git_read
non-variadic. Then it cannot have optional leading arguments.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Mon, 7 Apr 2025 21:12:56 +0000 (17:12 -0400)]
git-gui: cleanup git-bash menu item
git-gui on Git for Windows creates a menu item to start a git-bash
session for the current repository. This menu-item works as desired when
git-gui is installed in the Git for Windows (g4w) distribution, but
not when run from a different location such as normally done in
development. The reason is that git-bash's location is known to be
'/git-bash' in the Unix pathname space known to MSYS, but this is not
known in the Windows pathname space. Instead, git-gui derives a pathname
for git-bash assuming it is at a known relative location.
If git-gui is run from a different directory than assumed in g4w, the
relative location changes, and git-gui resorts to running a generic bash
login session in a Windows console.
But, the MSYS system underlying Git for Windows includes the 'cygpath'
utility to convert between Unix and Windows pathnames. Let's use this so
git-bash's Windows pathname is determined directly from /git-bash.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 26 Apr 2025 16:46:06 +0000 (18:46 +0200)]
git-gui: sanitize 'exec' arguments: background
As in the previous commits, introduce a function that sanitizes
arguments intended for the process, but runs the process in the
background. Convert 'exec' calls to use this new function.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Thu, 3 Apr 2025 04:37:08 +0000 (00:37 -0400)]
git-gui: avoid auto_execok in do_windows_shortcut
git-gui on Windows uses auto_execok to locate git-gui.exe,
which performs the same flawed search as does the builtin exec.
Use _which instead, performing a safe PATH lookup.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Mon, 21 Apr 2025 16:14:54 +0000 (18:14 +0200)]
git-gui: sanitize 'exec' arguments: simple cases
Tcl 'exec' assigns special meaning to its argument when they begin with
redirection, pipe or background operator. There are a number of
invocations of 'exec' which construct arguments that are taken from the
Git repository or a user input. However, when file names or ref names
are taken from the repository, it is possible to find names that have
these special forms. They must not be interpreted by 'exec' lest it
redirects input or output, or attempts to build a pipeline using a
command name controlled by the repository.
Introduce a helper function that identifies such arguments and prepends
"./" to force such a name to be regarded as a relative file name.
Convert those 'exec' calls where the arguments can simply be packed
into a list.
Note that most commands containing the word 'exec' route through
console::exec or console::chain, which we will treat in another commit.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Wed, 2 Apr 2025 21:37:27 +0000 (17:37 -0400)]
git-gui: avoid auto_execok for git-bash menu item
On Windows, git-gui offers to open a git-bash session for the current
repository from the menu, but uses [auto_execok start] to get the
command to actually run that shell.
The code for auto_execok, in /usr/share/tcl8.6/tcl.init, has 'start' in
the 'shellBuiltins' list for cmd.exe on Windows: as a result,
auto_execok does not actually search for start, meaning this usage is
technically ok with auto_execok now. However, leaving this use of
auto_execok in place will just induce confusion about why a known unsafe
function is being used on Windows. Instead, let's switch to using our
known safe _which function that looks only in $PATH, excluding the
current working directory.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Mon, 21 Apr 2025 15:07:10 +0000 (17:07 +0200)]
git-gui: treat file names beginning with "|" as relative paths
The Tcl 'open' function has a very wide interface. It can open files as
well as pipes to external processes. The difference is made only by the
first character of the file name: if it is "|", a process is spawned.
We have a number of calls of Tcl 'open' that take a file name from the
environment in which Git GUI is running. Be prepared that insane values
are injected. In particular, when we intend to open a file, do not take
a file name that happens to begin with "|" as a request to run a process.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Fri, 4 Apr 2025 20:55:59 +0000 (16:55 -0400)]
git-gui: remove unused proc is_shellscript
Commit 7d076d56757c (git-gui: handle shell script text filters when
loading for blame, 2011-12-09) added is_shellscript to test if a file
is executable by the shell, used only when searching for textconv
filters. The previous commit rearranged the tests for finding such
filters, and removed the only user of is_shellscript. Remove this
function.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 3 May 2025 11:37:35 +0000 (13:37 +0200)]
git-gui: remove git config --list handling for git < 1.5.3
git-gui uses `git config --null --list` to parse configuration. Git
versions prior to 1.5.3 do not have --null and need different treatment.
Nobody should be using such an old version anymore. (Moreover, since 0730a5a3a, git-gui requires git v2.36 or later). Keep only the code for
modern Git.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sun, 18 May 2025 14:08:06 +0000 (16:08 +0200)]
git-gui: remove special treatment of Windows from open_cmd_pipe
Commit 7d076d56757c (git-gui: handle shell script text filters when
loading for blame, 2011-12-09) added open_cmd_pipe to run text
conversion in support of blame, with special handling for shell
scripts on Windows. To determine whether the command is a shell
script, 'lindex' is used to pick off the first token from the command.
However, cmd is actually a command string taken from .gitconfig
literally and is not necessarily a syntactically correct Tcl list.
Hence, it cannot be processed by 'lindex' and 'lrange' reliably.
Pass the command string to the shell just like on non-Windows
platforms to avoid the potentially incorrect treatment.
A use of 'auto_execok' is removed by this change. This function is
dangerous on Windows, because it searches programs in the current
directory. Delegating the path lookup to the shell is safe, because
/bin/sh and /bin/bash follow POSIX on all platforms, including the
Git for Windows port.
A possible regression is that the old code, given filter command of
'foo', could find 'foo.bat' as a script, and not just bare 'foo', or
'foo.exe'. This rewrite requires explicitly giving the suffix if it is
not .exe.
This part of Git GUI can be exercised using
git gui blame -- some.file
while some.file has a textconv filter configured and has unstaged
modifications.
Helped-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Fri, 2 May 2025 15:39:55 +0000 (11:39 -0400)]
git-gui: remove HEAD detachment implementation for git < 1.5.3
git-gui provides an implementation to detach HEAD on Git versions prior
to 1.5.3. Nobody should be using such an old version anymore.
(Moreover, since 0730a5a3a, git-gui requires git v2.36 or later).
Keep only the code for modern Git.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
[j6t: message tweaked] Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Sun, 6 Apr 2025 22:20:14 +0000 (18:20 -0400)]
git-gui: use only the configured shell
git-gui has a few places where a bare "sh" is passed to exec, meaning
that the first instance of "sh" on $PATH will be used rather than the
shell configured. This violates expectations that the configured shell
is being used. Let's use [shellpath] everywhere.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Wed, 20 Sep 2023 21:56:14 +0000 (17:56 -0400)]
git-gui: remove Tcl 8.4 workaround on 2>@1 redirection
Since b792230 ("git-gui: Show a progress meter for checking out files",
2007-07-08), git-gui includes a workaround for Tcl that does not support
using 2>@1 to redirect stderr to stdout. Tcl added such support in
8.4.7, released in 2004, and this is fully supported in all 8.5
releases.
As git-gui has a hard-coded requirement for Tcl >= 8.5, the workaround
is no longer needed. Delete it.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Tue, 1 Apr 2025 15:45:06 +0000 (11:45 -0400)]
git-gui: make _shellpath usable on startup
Since commit d5257fb3c1de (git-gui: handle textconv filter on
Windows and in development, 2010-08-07), git-gui will search for a
usable shell if _shellpath is not configured, and on Windows may
resort to using auto_execok to find 'sh'. While this was intended for
development use, checks are insufficient to assure a proper
configuration when deployed where _shellpath is always set, but might
not give a usable shell.
Let's make this more robust by only searching if _shellpath was not
defined, and then using only our restricted search functions.
Furthermore, we should convert to a Windows path on Windows. Always
check for a valid shell on startup, meaning an absolute path to an
executable, aborting if these conditions are not met.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Wed, 2 Apr 2025 15:23:03 +0000 (11:23 -0400)]
git-gui: use [is_Windows], not bad _shellpath
Commit 7d076d56757c (git-gui: handle shell script text filters when
loading for blame, 2011-12-09) added open_cmd_pipe, with special
handling for Windows detected by seeing that _shellpath does not
point to an executable shell. That is bad practice, and is broken by
the next commit that assures _shellpath is valid on all platforms.
Fix this by using [is_Windows] as done for all Windows specific code.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Mark Levedahl [Thu, 3 Apr 2025 14:26:21 +0000 (10:26 -0400)]
git-gui: _which, only add .exe suffix if not present
The _which function finds executables on $PATH, and adds .exe on Windows
unless -script was given. However, win32.tcl executes "wscript.exe"
and "cscript.exe", both of which fail as _which adds .exe to both. This
is already fixed in git-gui released by Git for Windows. Do so here.
Signed-off-by: Mark Levedahl <mlevedahl@gmail.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Taylor Blau [Fri, 23 May 2025 21:04:21 +0000 (17:04 -0400)]
Merge branch 'js/fix-open-exec-2.40.0' into js/fix-open-exec
Branch js/fix-open-exec-2.40.0 converts `open` and `exec` calls to call
wrappers that sanitze the command arguments. This side branch updates
three `open` calls that are in conflict with the fix in the preceding
commit. To keep the intended operation of the 'open' calls, this merge
does not try to merge and resolve the conflicts, but ignores the
conversions that are brought in by the side branch, taking "ours" side
of the code in these three cases.
New fixes are the topic of the next commit.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
While "exec" uses a normal arguments list which is applied as
command + arguments (and redirections, etc), "open" uses a single
argument which is this command+arguments, where the command and
arguments are a list inside this one argument to "open".
Commit bb5cb23 (gitk: prevent overly long command lines 2023-05-08)
changed several values from individual arguments in that list (hashes
and file names), to a single value which is fed to git via redirection
to its stdin using "open" [1].
However, it didn't ensure correctly that this aggregate value in this
string is interpreted as a single element in this command+args list.
It did just enough so that newlines (which is how these elements are
concatenated) don't split this single list element.
A followup commit at the same patchset: 7dd272e (gitk: escape file
paths before piping to git log 2023-05-08) added a bit more, by
escaping backslahes and spaces at the file names, so that at least
it doesn't break when such file names get used there.
But these are not enough. At the very least tab is missing, and more,
and trying to manually escape every possible thing which can affect
how this string is interpreted in a list is a sub-par approach.
The solution is simply to tell tcl "this is a single list element".
which we can do by aggregating this value completely normally (hashes
and files separated by newlines), and then do [list $value].
So this is what this commit does, for all 3 places where bb5cb23
changed individual elements into an aggregate value.
[1]
That was not a fully accurate description. The accurate version
is that this string originally included two lists: hashes and files.
When used with "open" these lists correctly become the individual
elements of these lists, even if they contain spaces etc, so the
arguments which were used at this "git" commands were correct.
Commit bb5cb23 couldn't use these two lists as-is, because it needed
to process the individual elements in them (one element per line of
the aggregate value), and the issue is that ensuring this aggregate
is indeed interpreted as a single list element was sub-par.
Note: all the (double) quotes before/after the modification are not
required and with zero effect, even for \n. But this commit preserves
the original quoting form intentionally. It can be cleaned up later.
Signed-off-by: Avi Halachmi (:avih) <avihpit@yahoo.com> Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sun, 23 Mar 2025 21:34:11 +0000 (22:34 +0100)]
gitk: collect construction of blameargs into a single conditional
The command line to invoke 'git blame' for a single line is constructed
using several if-conditionals, each with the same condition
{$from_index new {}}. Merge all of them into a single conditional.
This requires to duplicate significant parts of the command, but it
helps the next change, where we will have to deal with a nested list
structure.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Thu, 20 Mar 2025 19:00:57 +0000 (20:00 +0100)]
gitk: sanitize 'open' arguments: simple commands with redirections
As in the previous commits, introduce a function that sanitizes
arguments intended for the process and in addition allows to pass
redirections, which are passed to Tcl's 'open' verbatim.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Thu, 20 Mar 2025 18:32:56 +0000 (19:32 +0100)]
gitk: sanitize 'open' arguments: simple commands
Tcl 'open' treats the second argument as a command when it begins
with |. The remainder of the argument is a list comprising the command
and its arguments. It assigns special meaning to these arguments when
they begin with a redirection, pipe or background operator. There are a
number of invocations of 'open' which construct arguments that are
taken from the Git repository or a user input. However, when file names
or ref names are taken from the repository, it is possible to find
names which have these special forms. They must not be interpreted by
'open' lest it redirects input or output, or attempts to build a
pipeline using a command name controlled by the repository.
Introduce a helper function that identifies such arguments and prepends
"./" to force such a name to be regarded as a relative file name.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 29 Mar 2025 16:35:19 +0000 (17:35 +0100)]
gitk: sanitize 'exec' arguments: redirect to process
Convert one 'exec' call that sends output to a process (pipeline).
Fortunately, the command does not contain any variables. For this
reason, just treat it as a "redirection".
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 29 Mar 2025 16:21:27 +0000 (17:21 +0100)]
gitk: sanitize 'exec' arguments: redirections and background
Convert 'exec' calls that both redirect output to a file and run the
process in the background. 'safe_exec_redirect' can take both these
"redirections" in the second argument simultaneously.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 29 Mar 2025 16:01:54 +0000 (17:01 +0100)]
gitk: sanitize 'exec' arguments: redirections
As in the previous commits, introduce a function that sanitizes
arguments intended for the process and in addition allows to pass
redirections verbatim, which are interpreted by Tcl's 'exec'.
Redirections can include the background operator '&'.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Sat, 29 Mar 2025 15:51:29 +0000 (16:51 +0100)]
gitk: sanitize 'exec' arguments: 'eval exec'
Convert calls of 'exec' where the arguments are already available in
a list and 'eval' is used to unpack the list. Use 'concat' to unite
the arguments into a single list before passing them to 'safe_exec'.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Mon, 17 Mar 2025 21:59:27 +0000 (22:59 +0100)]
gitk: sanitize 'exec' arguments: simple cases
Tcl 'exec' assigns special meaning to its argument when they begin with
redirection, pipe or background operator. There are a number of
invocations of 'exec' which construct arguments that are taken from the
Git repository or a user input. However, when file names or ref names
are taken from the repository, it is possible to find names with have
these special forms. They must not be interpreted by 'exec' lest it
redirects input or output, or attempts to build a pipeline using a
command name controlled by the repository.
Introduce a helper function that identifies such arguments and prepends
"./" to force such a name to be regarded as a relative file name.
Convert those 'exec' calls where the arguments can simply be packed
into a list.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Mon, 17 Mar 2025 20:39:58 +0000 (21:39 +0100)]
gitk: have callers of diffcmd supply pipe symbol when necessary
Function 'diffcmd' derives which of git diff-files, git diff-index, or
git diff-tree must be invoked depending on the ids provided. It puts
the pipe symbol as the first element of the returned command list.
Note though that of the four callers only two use the command with
Tcl 'open' and need the pipe symbol. The other two callers pass the
command to Tcl 'exec' and must remove the pipe symbol.
Do not include the pipe symbol in the constructed command list, but let
the call sites decide whether to add it or not. Note that Tcl 'open'
inspects only the first character of the command list, which is also
the first character of the first element in the list. For this reason,
it is valid to just tack on the pipe symbol with |$cmd and it is not
necessary to use [concat | $cmd].
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
Johannes Sixt [Mon, 17 Mar 2025 19:36:04 +0000 (20:36 +0100)]
gitk: treat file names beginning with "|" as relative paths
The Tcl 'open' function has a vary wide interface. It can open files as
well as pipes to external processes. The difference is made only by the
first character of the file name: if it is "|", an process is spawned.
We have a number of calls of Tcl 'open' that take a file name from the
environment in which Gitk is running. Be prepared that insane values are
injected. In particular, when we intend to open a file, do not mistake
a file name that happens to begin with "|" as a request to run a process.
Signed-off-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Taylor Blau <me@ttaylorr.com>
* maint-2.46:
Git 2.46.3
Git 2.45.3
Git 2.44.3
Git 2.43.6
Git 2.42.4
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.45:
Git 2.45.3
Git 2.44.3
Git 2.43.6
Git 2.42.4
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.44:
Git 2.44.3
Git 2.43.6
Git 2.42.4
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.43:
Git 2.43.6
Git 2.42.4
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.42:
Git 2.42.4
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.41:
Git 2.41.3
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
* maint-2.40:
Git 2.40.4
credential: disallow Carriage Returns in the protocol by default
credential: sanitize the user prompt
credential_format(): also encode <host>[:<port>]
t7300: work around platform-specific behaviour with long paths on MinGW
compat/regex: fix argument order to calloc(3)
mingw: drop bogus (and unneeded) declaration of `_pgmptr`
ci: remove 'Upload failed tests' directories' step from linux32 jobs
Printing unsanitized URLs when asking for credentials made the
user susceptible to crafted URLs (e.g. in recursive clones) that
mislead the user into typing in passwords for trusted sites that
would then be sent to untrusted sites instead.
- CVE-2024-52006
Git may pass on Carriage Returns via the credential protocol to
credential helpers which use line-reading functions that
interpret said Carriage Returns as line endings, even though Git
did not intend that.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
credential: disallow Carriage Returns in the protocol by default
While Git has documented that the credential protocol is line-based,
with newlines as terminators, the exact shape of a newline has not been
documented.
From Git's perspective, which is firmly rooted in the Linux ecosystem,
it is clear that "a newline" means a Line Feed character.
However, even Git's credential protocol respects Windows line endings
(a Carriage Return character followed by a Line Feed character, "CR/LF")
by virtue of using `strbuf_getline()`.
There is a third category of line endings that has been used originally
by MacOS, and that is respected by the default line readers of .NET and
node.js: bare Carriage Returns.
Git cannot handle those, and what is worse: Git's remedy against
CVE-2020-5260 does not catch when credential helpers are used that
interpret bare Carriage Returns as newlines.
Git Credential Manager addressed this as CVE-2024-50338, but other
credential helpers may still be vulnerable. So let's not only disallow
Line Feed characters as part of the values in the credential protocol,
but also disallow Carriage Return characters.
In the unlikely event that a credential helper relies on Carriage
Returns in the protocol, introduce an escape hatch via the
`credential.protectProtocol` config setting.
This addresses CVE-2024-52006.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When asking the user interactively for credentials, we want to avoid
misleading them e.g. via control sequences that pretend that the URL
targets a trusted host when it does not.
While Git learned, over the course of the preceding commits, to disallow
URLs containing URL-encoded control characters by default, credential
helpers are still allowed to specify values very freely (apart from Line
Feed and NUL characters, anything is allowed), and this would allow,
say, a username containing control characters to be specified that would
then be displayed in the interactive terminal prompt asking the user for
the password, potentially sending those control characters directly to
the terminal. This is undesirable because control characters can be used
to mislead users to divulge secret information to untrusted sites.
To prevent such an attack vector, let's add a `git_prompt()` that forces
the displayed text to be sanitized, i.e. displaying question marks
instead of control characters.
Note: While this commit's diff changes a lot of `user@host` strings to
`user%40host`, which may look suspicious on the surface, there is a good
reason for that: this string specifies a user name, not a
<username>@<hostname> combination! In the context of t5541, the actual
combination looks like this: `user%40@127.0.0.1:5541`. Therefore, these
string replacements document a net improvement introduced by this
commit, as `user@host@127.0.0.1` could have left readers wondering where
the user name ends and where the host name begins.
Hinted-at-by: Jeff King <peff@peff.net> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
An upcoming change wants to sanitize the credential password prompt
where a URL is displayed that may potentially come from a `.gitmodules`
file. To this end, the `credential_format()` function is employed.
To sanitize the host name (and optional port) part of the URL, we need a
new mode of the `strbuf_add_percentencode()` function because the
current mode is both too strict and too lenient: too strict because it
encodes `:`, `[` and `]` (which should be left unencoded in
`<host>:<port>` and in IPv6 addresses), and too lenient because it does
not encode invalid host name characters `/`, `_` and `~`.
So let's introduce and use a new mode specifically to encode the host
name and optional port part of a URI, leaving alpha-numerical
characters, periods, colons and brackets alone and encoding all others.
This only leads to a change of behavior for URLs that contain invalid
host names.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Junio C Hamano [Mon, 25 Nov 2024 03:29:39 +0000 (12:29 +0900)]
Merge branch 'jk/output-prefix-cleanup' into maint-2.47
Code clean-up.
* jk/output-prefix-cleanup:
diff: store graph prefix buf in git_graph struct
diff: return line_prefix directly when possible
diff: return const char from output_prefix callback
diff: drop line_prefix_length field
line-log: use diff_line_prefix() instead of custom helper
Junio C Hamano [Mon, 25 Nov 2024 03:20:42 +0000 (12:20 +0900)]
Merge branch 'master' of https://github.com/j6t/gitk into maint-2.47
* 'master' of https://github.com/j6t/gitk:
Makefile(s): avoid recipe prefix in conditional statements
doc: switch links to https
doc: update links to current pages
Taylor Blau [Mon, 8 Apr 2024 15:51:44 +0000 (11:51 -0400)]
Makefile(s): avoid recipe prefix in conditional statements
In GNU Make commit 07fcee35 ([SV 64815] Recipe lines cannot contain
conditional statements, 2023-05-22) and following, conditional
statements may no longer be preceded by a tab character (which Make
refers to as the recipe prefix).
There are a handful of spots in our various Makefile(s) which will break
in a future release of Make containing 07fcee35. For instance, trying to
compile the pre-image of this patch with the tip of make.git results in
the following:
$ make -v | head -1 && make
GNU Make 4.4.90
config.mak.uname:842: *** missing 'endif'. Stop.
The kernel addressed this issue in 82175d1f9430 (kbuild: Replace tabs
with spaces when followed by conditionals, 2024-01-28). Address the
issues in Git's tree by applying the same strategy.
When a conditional word (ifeq, ifneq, ifdef, etc.) is preceded by one or
more tab characters, replace each tab character with 8 space characters
with the following:
The "unless /\\$/" removes any false-positives (like "\telse \"
appearing within a shell script as part of a recipe).
After doing so, Git compiles on newer versions of Make:
$ make -v | head -1 && make
GNU Make 4.4.90
GIT_VERSION = 2.44.0.414.gfac1dc44ca9
[...]
$ echo $?
0
Reported-by: Dario Gjorgjevski <dario.gjorgjevski@gmail.com> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cherry-picked-from: 728b9ac0c3b93aaa4ea80280c591deb198051785 Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Josh Soref [Fri, 24 Nov 2023 03:35:13 +0000 (03:35 +0000)]
doc: switch links to https
These sites offer https versions of their content.
Using the https versions provides some protection for users.
Signed-off-by: Josh Soref <jsoref@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cherry-picked-from: d05b08cd52cfda627f1d865bdfe6040a2c9521b5 Signed-off-by: Johannes Sixt <j6t@kdbg.org>
projects / thirdparty / git.git / log
