From owner-freebsd-security@FreeBSD.ORG Sun May 8 17:39:46 2011 Return-Path: Delivered-To: freebsd-security@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 56D5F1065670 for ; Sun, 8 May 2011 17:39:46 +0000 (UTC) (envelope-from jhellenthal@gmail.com) Received: from mail-iw0-f182.google.com (mail-iw0-f182.google.com [209.85.214.182]) by mx1.freebsd.org (Postfix) with ESMTP id 08B9A8FC12 for ; Sun, 8 May 2011 17:39:45 +0000 (UTC) Received: by iwn33 with SMTP id 33so5384511iwn.13 for ; Sun, 08 May 2011 10:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:sender:date:from:to:cc:subject:message-id :references:mime-version:content-type:content-disposition :in-reply-to:x-openpgp-key-id:x-openpgp-key-fingerprint :x-openpgp-key-url; bh=PxoJg56HiR5/7SLZQsX86qt8ftYuCFGax2fmEnCKIFg=; b=eQc2FwVebYlphp6BPoEtzIcDdckEP2gT1j/DmuHS2Jnbfstn5VVQdKtmOjYUDtUttB xtRx8uoyp5x3TIRYp9bfMtQZItpEseON3QLixmJUO92+2YjQzv6deV0FNPYE5K0C9IbO 2ZiUM5XwpsnBIugot7HJAmuAsQlq4dRaeWVjc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:x-openpgp-key-id :x-openpgp-key-fingerprint:x-openpgp-key-url; b=D4bFYHjfmtKuMK7+mJ0kiaP2nAizO+VNiwdzS7n/m71+4bHen4Z+GXYyRyR30KCc8Q fJyKC3kbvBBt9y39ofA9aGw3weH3Y1lbJax2iJqNvrfNtasE0zTSm74uFwFpuJZcbZsQ JkNh2t9E+969mv3sSxrBj2VSgcpEBDeebXV5U= Received: by 10.42.108.137 with SMTP id h9mr5425446icp.112.1304876383982; Sun, 08 May 2011 10:39:43 -0700 (PDT) Received: from DataIX.net (adsl-99-190-84-116.dsl.klmzmi.sbcglobal.net [99.190.84.116]) by mx.google.com with ESMTPS id f7sm2265256ibn.41.2011.05.08.10.39.41 (version=TLSv1/SSLv3 cipher=OTHER); Sun, 08 May 2011 10:39:42 -0700 (PDT) Sender: "J. Hellenthal" Received: from DataIX.net (localhost [127.0.0.1]) by DataIX.net (8.14.4/8.14.4) with ESMTP id p48HdZ05002989 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 8 May 2011 13:39:35 -0400 (EDT) (envelope-from jhell@DataIX.net) Received: (from jhell@localhost) by DataIX.net (8.14.4/8.14.4/Submit) id p48HdVCe002988; Sun, 8 May 2011 13:39:31 -0400 (EDT) (envelope-from jhell@DataIX.net) Date: Sun, 8 May 2011 13:39:31 -0400 From: Jason Hellenthal To: Chris Rees Message-ID: <20110508173931.GA2757@DataIX.net> References: <4DC40E21.6040503@gmail.com> <4DC4102E.8000700@gmail.com> <201105072231.p47MVktY035491@catflap.bishopston.net> <20110508075203.GA61754@DataIX.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="RnlQjJ0d97Da+TV1" Content-Disposition: inline In-Reply-To: X-OpenPGP-Key-Id: 0x89D8547E X-OpenPGP-Key-Fingerprint: 85EF E26B 07BB 3777 76BE B12A 9057 8789 89D8 547E X-OpenPGP-Key-URL: http://bit.ly/0x89D8547E Cc: Jamie Landeg Jones , freebsd-security@freebsd.org, feld@feld.me, Edho P Arief Subject: Re: Rooting FreeBSD , Privilege Escalation using Jails (P??????tur) X-BeenThere: freebsd-security@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Security issues \[members-only posting\]" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 May 2011 17:39:46 -0000 --RnlQjJ0d97Da+TV1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Chris, On Sun, May 08, 2011 at 09:58:05AM +0100, Chris Rees wrote: > On 8 May 2011 08:52, Jason Hellenthal wrote: > > > > Edho, > > > > On Sun, May 08, 2011 at 09:15:28AM +0700, Edho P Arief wrote: > >> On Sun, May 8, 2011 at 5:31 AM, Jamie Landeg Jones wrote: > >> >> All the same, I've sent a PR [1] with some doc patches to make peop= le > >> >> more aware of this -- fulfilling my promise of 2+ years ago :S > >> >> > >> >> Thanks! > >> >> > >> >> Chris > >> >> > >> >> [1] http://www.freebsd.org/cgi/query-pr.cgi?pr=3D156853 > >> > > >> > Um. Some problems here. > >> > > >> > A jail won't work for not-root users if the jail root directory is c= hmod 700 - although > >> > there is obviously a 'chroot' running withing the jail, the jailed u= ser still needs > >> > to have read permission from the hosts / -- chmod 700 therefore lock= s all non-root > >> > users out. > >> > > >> > >> It's weird - I don't remember having such problem after setting jails' > >> root directory permission to 700. I don't have the system anymore so I > >> can't verify it just yet. > > > > It should also be noted here that the jailed root user also has permiss= ion > > to chmod(1) '/' to anything he or she wants unless you have taken > > precaution to not allow that. I would reccoment storing your jails two > > levels deep into a directory and chmod(1) 700 the first level to prevent > > access from the host and from the jailed root user changing the perms. > > >=20 > Oops, you're absolutely right. >=20 > I've updated the docs patches (links at [1]), though unfortunately it > means it's a little less elegant; I'm reluctant to suggest >=20 > # chmod 0700 $D/.. >=20 Haha I would strongly suggest against that ;) Not knowing where people are= =20 keeping the jails would impose quite a bit of harm if they did have them=20 in places like that or /var/jailname. Unfortunately in this case we can=20 only update the docs and hope that the user will keep up-to-date with=20 reading them. Only other possibility I see is ensuring that noone inside the jail can=20 chmod or do anyting on / but this may actually be quite tough. > in case someone sets $D to /usr/local/myjail or similar... >=20 > Chris >=20 > [1] http://www.freebsd.org/cgi/query-pr.cgi?pr=3Ddocs/156853 --=20 Regards, (jhell) Jason Hellenthal --RnlQjJ0d97Da+TV1 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (FreeBSD) Comment: http://bit.ly/0x89D8547E iQEcBAEBAgAGBQJNxtVSAAoJEJBXh4mJ2FR+sB4H/3PoFa0YLpO+TWZUvvtq6lpB EEuwDlGgdgy9kr49LzHX8rAM/cMpOcVF2J2+oODHJDLFLHX+osyVSgkyWUp98BkP znPsN16dEOEChjQPL6oNY2JkOZMFLUZnTq1oAq0/pplc4xXQyE4oyidqVm6Qhp16 2G3gk+8aDOHYOFQxzt81Lusi5VEOxobkWI1CqB/Xakw+z43UaOD/wkY7T4tlJjKf CNKQToRzjAUxyPNVa1kYCGdzPQTowvvgvKTCWL6naO/9QkBAYEIexru2YdP1JdZS 1MNo/ZzPUGjQJrnfBfThYvUI5G1uOYRPCBgw46+RG4bSvSpA+Bf6SwOKlTGzxkY= =OWgi -----END PGP SIGNATURE----- --RnlQjJ0d97Da+TV1--