Commit Graph

24 Commits

Author SHA1 Message Date
Elijah Newren
36bf195890 alloc.h: move ALLOC_GROW() functions from cache.h
This allows us to replace includes of cache.h with includes of the much
smaller alloc.h in many places.  It does mean that we also need to add
includes of alloc.h in a number of C files.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-02-23 17:25:28 -08:00
Kevin Backhouse
0ca6ead81e alias.c: reject too-long cmdline strings in split_cmdline()
This function improperly uses an int to represent the number of entries
in the resulting argument array. This allows a malicious actor to
intentionally overflow the return value, leading to arbitrary heap
writes.

Because the resulting argv array is typically passed to execv(), it may
be possible to leverage this attack to gain remote code execution on a
victim machine. This was almost certainly the case for certain
configurations of git-shell until the previous commit limited the size
of input it would accept. Other calls to split_cmdline() are typically
limited by the size of argv the OS is willing to hand us, so are
similarly protected.

So this is not strictly fixing a known vulnerability, but is a hardening
of the function that is worth doing to protect against possible unknown
vulnerabilities.

One approach to fixing this would be modifying the signature of
`split_cmdline()` to look something like:

    int split_cmdline(char *cmdline, const char ***argv, size_t *argc);

Where the return value of `split_cmdline()` is negative for errors, and
zero otherwise. If non-NULL, the `*argc` pointer is modified to contain
the size of the `**argv` array.

But this implies an absurdly large `argv` array, which more than likely
larger than the system's argument limit. So even if split_cmdline()
allowed this, it would fail immediately afterwards when we called
execv(). So instead of converting all of `split_cmdline()`'s callers to
work with `size_t` types in this patch, instead pursue the minimal fix
here to prevent ever returning an array with more than INT_MAX entries
in it.

Signed-off-by: Kevin Backhouse <kevinbackhouse@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
2022-10-01 00:23:38 -04:00
Nguyễn Thái Ngọc Duy
a7412ae134 alias.c: mark split_cmdline_strerror() strings for translation
This function can be part of translated messages. To make sure we
don't have a sentence with mixed languages, mark the strings for
translation, but only use translated strings in places we know we will
output translated strings.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-12 14:47:09 +09:00
Nguyễn Thái Ngọc Duy
3301d36b29 completion: add and use --list-cmds=alias
By providing aliases via --list-cmds=, we could simplify command
collection code in the script. We only issue one git command. Before
this patch that is "git config", after it's "git --list-cmds=". In
"git help" completion case we actually reduce one "git" process (for
getting guides) but that call was added in this series so it does not
really count.

A couple of bash functions are removed because they are not needed
anymore. __git_compute_all_commands() and $__git_all_commands stay
because they are still needed for completing pager.* config and
without "alias" group, the result is still cacheable.

There is a slight (good) change in _git_help() with this patch: before
"git help <tab>" shows external commands (as in _not_ part of git) as
well as part of $__git_all_commands. We have finer control over
command listing now and can exclude that because we can't provide a
man page for external commands anyway.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-21 13:23:14 +09:00
Nguyễn Thái Ngọc Duy
65b5f9483e Move declaration for alias.c to alias.h
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-05-21 13:23:14 +09:00
Junio C Hamano
099b74b4b2 Merge branch 'js/alias-case-sensitivity'
A recent update broke an alias that contained an uppercase letter.

* js/alias-case-sensitivity:
  alias: compare alias name *case-insensitively*
  t1300: demonstrate that CamelCased aliases regressed
2017-07-20 16:29:59 -07:00
Johannes Schindelin
643df7e234 alias: compare alias name *case-insensitively*
It is totally legitimate to add CamelCased aliases, but due to the way
config keys are compared, the case does not matter.

Therefore, we must compare the alias name insensitively to the config
keys.

This fixes a regression introduced by a9bcf6586d (alias: use
the early config machinery to expand aliases, 2017-06-14).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-17 14:00:12 -07:00
Junio C Hamano
50f03c6676 Merge branch 'ab/free-and-null'
A common pattern to free a piece of memory and assign NULL to the
pointer that used to point at it has been replaced with a new
FREE_AND_NULL() macro.

* ab/free-and-null:
  *.[ch] refactoring: make use of the FREE_AND_NULL() macro
  coccinelle: make use of the "expression" FREE_AND_NULL() rule
  coccinelle: add a rule to make "expression" code use FREE_AND_NULL()
  coccinelle: make use of the "type" FREE_AND_NULL() rule
  coccinelle: add a rule to make "type" code use FREE_AND_NULL()
  git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
2017-06-24 14:28:41 -07:00
Ævar Arnfjörð Bjarmason
6a83d90207 coccinelle: make use of the "type" FREE_AND_NULL() rule
Apply the result of the just-added coccinelle rule. This manually
excludes a few occurrences, mostly things that resulted in many
FREE_AND_NULL() on one line, that'll be manually fixed in a subsequent
change.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-16 12:44:03 -07:00
Brandon Williams
b2141fc1d2 config: don't include config.h by default
Stop including config.h by default in cache.h.  Instead only include
config.h in those files which require use of the config system.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 12:56:22 -07:00
Johannes Schindelin
a9bcf6586d alias: use the early config machinery to expand aliases
Instead of discovering the .git/ directory, reading the config and then
trying to painstakingly reset all the global state if we did not find a
matching alias, let's use the early config machinery instead.

It may look like unnecessary work to discover the .git/ directory in the
early config machinery and then call setup_git_directory_gently() in the
case of a shell alias, repeating the very same discovery *again*.
However, we have to do this as the early config machinery takes pains
*not* to touch any global state, while shell aliases expect a possibly
changed working directory and at least the GIT_PREFIX and GIT_DIR
variables to be set.

This change also fixes a known issue where Git tried to read the pager
config from an incorrect path in a subdirectory of a Git worktree if an
alias expanded to a shell command.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 12:31:50 -07:00
Jeff King
b32fa95fd8 convert trivial cases to ALLOC_ARRAY
Each of these cases can be converted to use ALLOC_ARRAY or
REALLOC_ARRAY, which has two advantages:

  1. It automatically checks the array-size multiplication
     for overflow.

  2. It always uses sizeof(*array) for the element-size,
     so that it can never go out of sync with the declared
     type of the array.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-02-22 14:51:09 -08:00
Jeff King
9e9de18f1a config: silence warnings for command names with invalid keys
When we are running the git command "foo", we may have to
look up the config keys "pager.foo" and "alias.foo". These
config schemes are mis-designed, as the command names can be
anything, but the config syntax has some restrictions. For
example:

  $ git foo_bar
  error: invalid key: pager.foo_bar
  error: invalid key: alias.foo_bar
  git: 'foo_bar' is not a git command. See 'git --help'.

You cannot name an alias with an underscore. And if you have
an external command with one, you cannot configure its
pager.

In the long run, we may develop a different config scheme
for these features. But in the near term (and because we'll
need to support the existing scheme indefinitely), we should
at least squelch the error messages shown above.

These errors come from git_config_parse_key. Ideally we
would pass a "quiet" flag to the config machinery, but there
are many layers between the pager code and the key parsing.
Passing a flag through all of those would be an invasive
change.

Instead, let's provide a config function to report on
whether a key is syntactically valid, and have the pager and
alias code skip lookup for bogus keys. We can build this
easily around the existing git_config_parse_key, with two
minor modifications:

  1. We now handle a NULL store_key, to validate but not
     write out the normalized key.

  2. We accept a "quiet" flag to avoid writing to stderr.
     This doesn't need to be a full-blown public "flags"
     field, because we can make the existing implementation
     a static helper function, keeping the mess contained
     inside config.c.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-08-24 08:52:23 -07:00
Tanay Abhra
111791559e alias.c: replace git_config() with git_config_get_string()
Use `git_config_get_string()` instead of `git_config()` to take advantage of
the config-set API which provides a cleaner control flow.

Signed-off-by: Tanay Abhra <tanayabh@gmail.com>
Reviewed-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-08-07 13:33:29 -07:00
Jeff King
ae021d8791 use skip_prefix to avoid magic numbers
It's a common idiom to match a prefix and then skip past it
with a magic number, like:

  if (starts_with(foo, "bar"))
	  foo += 3;

This is easy to get wrong, since you have to count the
prefix string yourself, and there's no compiler check if the
string changes.  We can use skip_prefix to avoid the magic
numbers here.

Note that some of these conversions could be much shorter.
For example:

  if (starts_with(arg, "--foo=")) {
	  bar = arg + 6;
	  continue;
  }

could become:

  if (skip_prefix(arg, "--foo=", &bar))
	  continue;

However, I have left it as:

  if (skip_prefix(arg, "--foo=", &v)) {
	  bar = v;
	  continue;
  }

to visually match nearby cases which need to actually
process the string. Like:

  if (skip_prefix(arg, "--foo=", &v)) {
	  bar = atoi(v);
	  continue;
  }

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:45 -07:00
Christian Couder
5955654823 replace {pre,suf}fixcmp() with {starts,ends}_with()
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.

The change can be recreated by mechanically applying this:

    $ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
      grep -v strbuf\\.c |
      xargs perl -pi -e '
        s|!prefixcmp\(|starts_with\(|g;
        s|prefixcmp\(|!starts_with\(|g;
        s|!suffixcmp\(|ends_with\(|g;
        s|suffixcmp\(|!ends_with\(|g;
      '

on the result of preparatory changes in this series.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05 14:13:21 -08:00
Felipe Contreras
cc10837929 alias: have SP around arithmetic operators
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-10-16 10:27:26 -07:00
Greg Brockman
ad9ac6db5d split_cmdline: Allow caller to access error string
This allows the caller to add its own error message to that returned
by split_cmdline.  Thus error output following a failed split_cmdline
can be of the form

fatal: Bad alias.test string: cmdline ends with \

rather than

error: cmdline ends with \
fatal: Bad alias.test string

Signed-off-by: Greg Brockman <gdb@mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-11 09:36:23 -07:00
Junio C Hamano
2beba6beb0 Merge branch 'jk/maint-1.6.0-trace-argv'
* jk/maint-1.6.0-trace-argv:
  fix GIT_TRACE segfault with shell-quoted aliases

Conflicts:
	alias.c
2009-05-23 01:39:08 -07:00
Jeff King
27d5438d9f fix GIT_TRACE segfault with shell-quoted aliases
The alias argv comes from the split_cmdline function, which
splits the config text for the alias into an array of
strings. It returns the number of elements in the array, but
does not actually put a NULL at the end of the array.
Later, the trace function tries to print this argv and
assumes that it has the trailing NULL.

The split_cmdline function is probably at fault, since argv
lists almost always end with a NULL signal. This patch adds
one, in addition to the returned count; this doesn't hurt
the other callers at all, since they were presumably using
the count already (and will never look at the NULL).

While we're there and using ALLOC_GROW, let's clean up the
other manual grow.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-05-09 01:39:40 -07:00
Felipe Contreras
4b25d091ba Fix a bunch of pointer declarations (codestyle)
Essentially; s/type* /type */ as per the coding guidelines.

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-05-01 15:17:31 -07:00
Miklos Vajna
0989fe9623 Move split_cmdline() to alias.c
split_cmdline() is currently used for aliases only, but later it can be
useful for other builtins as well. Move it to alias.c for now,
indicating that originally it's for aliases, but we'll have it in libgit
this way.

Signed-off-by: Miklos Vajna <vmiklos@frugalware.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-30 22:45:50 -07:00
Johannes Schindelin
ef90d6d420 Provide git_config with a callback-data parameter
git_config() only had a function parameter, but no callback data
parameter.  This assumes that all callback functions only modify
global variables.

With this patch, every callback gets a void * parameter, and it is hoped
that this will help the libification effort.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-05-14 12:34:44 -07:00
Jeff King
94351118c0 make alias lookup a public, procedural function
This converts git_config_alias to the public alias_lookup
function. Because of the nature of our config parser, we
still have to rely on setting static data. However, that
interface is wrapped so that you can just say

  value = alias_lookup(key);

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-24 18:31:49 -08:00