Revision 3ec804490a265f4c418a321428c12f3f18b7eff5 authored by Jeff King on 29 April 2017, 12:36:44 UTC, committed by Junio C Hamano on 05 May 2017, 03:07:27 UTC
When a remote server uses git-shell, the client side will
connect to it like:
ssh server "git-upload-pack 'foo.git'"
and we literally exec ("git-upload-pack", "foo.git"). In
early versions of upload-pack and receive-pack, we took a
repository argument and nothing else. But over time they
learned to accept dashed options. If the user passes a
repository name that starts with a dash, the results are
confusing at best (we complain of a bogus option instead of
a non-existent repository) and malicious at worst (the user
can start an interactive pager via "--help").
We could pass "--" to the sub-process to make sure the
user's argument is interpreted as a branch name. I.e.:
git-upload-pack -- -foo.git
But adding "--" automatically would make us inconsistent
with a normal shell (i.e., when git-shell is not in use),
where "-foo.git" would still be an error. For that case, the
client would have to specify the "--", but they can't do so
reliably, as existing versions of git-shell do not allow
more than a single argument.
The simplest thing is to simply disallow "-" at the start of
the repo name argument. This hasn't worked either with or
without git-shell since version 1.0.0, and nobody has
complained.
Note that this patch just applies to do_generic_cmd(), which
runs upload-pack, receive-pack, and upload-archive. There
are two other types of commands that git-shell runs:
- do_cvs_cmd(), but this already restricts the argument to
be the literal string "server"
- admin-provided commands in the git-shell-commands
directory. We'll pass along arbitrary arguments there,
so these commands could have similar problems. But these
commands might actually understand dashed arguments, so
we cannot just block them here. It's up to the writer of
the commands to make sure they are safe. With great
power comes great responsibility.
Reported-by: Timo Schmid <tschmid@ernw.de>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 7654286
sha1-array.c
#include "cache.h"
#include "sha1-array.h"
#include "sha1-lookup.h"
void sha1_array_append(struct sha1_array *array, const unsigned char *sha1)
{
ALLOC_GROW(array->sha1, array->nr + 1, array->alloc);
hashcpy(array->sha1[array->nr++], sha1);
array->sorted = 0;
}
static int void_hashcmp(const void *a, const void *b)
{
return hashcmp(a, b);
}
static void sha1_array_sort(struct sha1_array *array)
{
qsort(array->sha1, array->nr, sizeof(*array->sha1), void_hashcmp);
array->sorted = 1;
}
static const unsigned char *sha1_access(size_t index, void *table)
{
unsigned char (*array)[20] = table;
return array[index];
}
int sha1_array_lookup(struct sha1_array *array, const unsigned char *sha1)
{
if (!array->sorted)
sha1_array_sort(array);
return sha1_pos(sha1, array->sha1, array->nr, sha1_access);
}
void sha1_array_clear(struct sha1_array *array)
{
free(array->sha1);
array->sha1 = NULL;
array->nr = 0;
array->alloc = 0;
array->sorted = 0;
}
void sha1_array_for_each_unique(struct sha1_array *array,
for_each_sha1_fn fn,
void *data)
{
int i;
if (!array->sorted)
sha1_array_sort(array);
for (i = 0; i < array->nr; i++) {
if (i > 0 && !hashcmp(array->sha1[i], array->sha1[i-1]))
continue;
fn(array->sha1[i], data);
}
}
Computing file changes ...
