From owner-freebsd-jail@freebsd.org Tue Mar 15 18:20:09 2016 Return-Path: Delivered-To: freebsd-jail@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 83929AD215A for ; Tue, 15 Mar 2016 18:20:09 +0000 (UTC) (envelope-from jamie@freebsd.org) Received: from gritton.org (gritton.org [162.220.209.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "www.gritton.org", Issuer "StartCom Class 1 Primary Intermediate Server CA" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 6A75D144D; Tue, 15 Mar 2016 18:20:09 +0000 (UTC) (envelope-from jamie@freebsd.org) Received: from gritton.org (gritton.org [162.220.209.3]) by gritton.org (8.15.2/8.15.2) with ESMTPS id u2FI8XMB069210 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Tue, 15 Mar 2016 12:08:33 -0600 (MDT) (envelope-from jamie@freebsd.org) Received: (from www@localhost) by gritton.org (8.15.2/8.15.2/Submit) id u2FI8Xq0069209; Tue, 15 Mar 2016 12:08:33 -0600 (MDT) (envelope-from jamie@freebsd.org) X-Authentication-Warning: gritton.org: www set sender to jamie@freebsd.org using -f To: freebsd-jail@freebsd.org Subject: Re: SHM objects cannot be isolated in jails, any evolution in future FreeBSD versions? X-PHP-Originating-Script: 0:rcube.php MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 15 Mar 2016 12:08:33 -0600 From: James Gritton In-Reply-To: <593EB477-D6AC-463B-A509-86A63455436F@exonetric.com> References: <0ad738494152d249f3bbe3b722a46bd2@gritton.org> <1457989662.568170.549069906.791C2D05@webmail.messagingengine.com> <56E7C926.3020201@quip.cz> <593EB477-D6AC-463B-A509-86A63455436F@exonetric.com> Message-ID: <8a3aba735138ade07cad0315dcabee69@gritton.org> X-Sender: jamie@freebsd.org User-Agent: Roundcube Webmail/1.1.2 X-BeenThere: freebsd-jail@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Discussion about FreeBSD jail\(8\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Mar 2016 18:20:09 -0000 On 2016-03-15 06:33, Mark Blackman wrote: > On 15 Mar 2016, at 08:34, Miroslav Lachman <000.fbsd@quip.cz> wrote: >> Mark Felder wrote on 03/14/2016 22:07: >>>> On Sat, Mar 12, 2016, at 11:42, James Gritton wrote: >>>>> On 2016-03-12 04:05, Simon wrote: >>>>> The shm_open()(2) function changed since FreeBSD 7.0: the SHM >>>>> objects >>>>> path are now uncorrelated from the physical file system to become >>>>> just >>>>> abstract objects. Probably due to this, the jail system do not >>>>> provide >>>>> any form of filtering regarding shared memory created using this >>>>> function. Therefore: >>>>> >>>>> - Anyone can create unauthorized communication channels between >>>>> jails, >>>>> - Users with enough privileges in any jail can access and modify >>>>> any >>>>> SHM objects system-wide, ie. shared memory objects created in any >>>>> other jail and in the host system. >>>>> >>>>> I've seen a few claims that SHM objects were being handled >>>>> differently >>>>> whether they were created inside or outside a jail. However, I >>>>> tested >>>>> on FreeBSD 10.1 and 9.3 but found no evidence of this: both version >>>>> were affected by the same issue. >>>>> >>>>> A reference of such claim: >>>>> https://lists.freebsd.org/pipermail/freebsd-ports-bugs/2015-July/312665.html >>>>> >>>>> My initial post on FreeBSD forum discussing the issue with more >>>>> details: https://forums.freebsd.org/threads/55468/ >>>>> >>>>> Currently, there does not seem to be any way to prevent this. >>>>> >>>>> I'm therefore wondering if there are any concrete plans to change >>>>> this >>>>> situation in future FreeBSD versions? Be able to block the >>>>> currently >>>>> free inter-jail SHM-based communication seems a minimum, however >>>>> such >>>>> setting would also most likely prevent SHM-based application to >>>>> work. >>>>> >>>>> Using file based SHM objects in jails seemed a good ideas but it >>>>> does >>>>> not seem implemented this way, I don't know why. Is this planned, >>>>> or >>>>> are there any greater plans ongoing also involving IPC's similar >>>>> issue? >>>> >>>> There are no concrete plans I'm aware of, but it's definitely a >>>> thing >>>> that should be done. How about filing a bug report for it? You've >>>> already got a good write-up of the situation. >>> >>> Both this and SYSV IPC jail support[1] are badly needed. >>> >>> [1] https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=48471 >> >> Yes, it is very sad that original patch was not commited, nor >> commented or improved by core developers for long 13 years. I am not >> 100% sure but I thing there was some patch from PJD for SysV IPC too. >> There were EclipseBSD with resource limits in times of FreeBSD 3.4 and >> there is FreeVPS for 6.x with virtualized IPC... >> >> So I really hope SysV IPC aware jails will become reality soon. >> >> Miroslav Lachman > > Do we have a feeling if this only a funding problem or is it an > enthusiasm problem? > > - Mark More of an "I've been hearing about it being around the corner so haven't done anything" problem. I guess that would file under enthusiasm. - Jamie