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
kwset.h
/* This file has been copied from commit e7ac713d^ in the GNU grep git
* repository. A few small changes have been made to adapt the code to
* Git.
*/
/* kwset.h - header declaring the keyword set library.
Copyright (C) 1989, 1998, 2005 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
/* Written August 1989 by Mike Haertel.
The author may be reached (Email) at the address mike@ai.mit.edu,
or (US mail) as Mike Haertel c/o Free Software Foundation. */
struct kwsmatch
{
int index; /* Index number of matching keyword. */
size_t offset[1]; /* Offset of each submatch. */
size_t size[1]; /* Length of each submatch. */
};
struct kwset_t;
typedef struct kwset_t* kwset_t;
/* Return an opaque pointer to a newly allocated keyword set, or NULL
if enough memory cannot be obtained. The argument if non-NULL
specifies a table of character translations to be applied to all
pattern and search text. */
extern kwset_t kwsalloc(unsigned char const *);
/* Incrementally extend the keyword set to include the given string.
Return NULL for success, or an error message. Remember an index
number for each keyword included in the set. */
extern const char *kwsincr(kwset_t, char const *, size_t);
/* When the keyword set has been completely built, prepare it for
use. Return NULL for success, or an error message. */
extern const char *kwsprep(kwset_t);
/* Search through the given buffer for a member of the keyword set.
Return a pointer to the leftmost longest match found, or NULL if
no match is found. If foundlen is non-NULL, store the length of
the matching substring in the integer it points to. Similarly,
if foundindex is non-NULL, store the index of the particular
keyword found therein. */
extern size_t kwsexec(kwset_t, char const *, size_t, struct kwsmatch *);
/* Deallocate the given keyword set and all its associated storage. */
extern void kwsfree(kwset_t);
Computing file changes ...
