From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Am=C3=A9rico_Wang?= Subject: Re: About ACL for IPC Object Date: Fri, 22 Jan 2010 18:02:47 +0800 Message-ID: <2375c9f91001220202m724e2ee2p2213b81a043ebd33@mail.gmail.com> References: <6fb445941001200112o2934f805l4eb4f78000e9527e@mail.gmail.com> <6fb445941001200120m3aa5e944j54a6f645ce82d76f@mail.gmail.com> <4B57C3C3.9010606@schaufler-ca.com> <20100121090510.GA908@infradead.org> <6fb445941001220115y6b99f7b4g306ea23d3202969@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Christoph Hellwig , Casey Schaufler , sds@tycho.nsa.gov, jra@samba.org, linux-security-module@vger.kernel.org, linux-next@vger.kernel.org, LKML , linux-fsdevel@vger.kernel.org To: zhou peng Return-path: In-Reply-To: <6fb445941001220115y6b99f7b4g306ea23d3202969@mail.gmail.com> Sender: linux-security-module-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org (Top-posting fixed.) On Fri, Jan 22, 2010 at 5:15 PM, zhou peng wrote= : > > 2010/1/21 Christoph Hellwig : >> On Wed, Jan 20, 2010 at 07:02:27PM -0800, Casey Schaufler wrote: >>> zhou peng wrote: >>> > Hi all, >>> > >>> > There are ACL in file system, but why there are no ACL implementa= tion >>> > in IPC object, eg. shm, message queue, FIFO? >>> > >>> >>> Most people haven't noticed that IPC objects are even there, much l= ess >>> that they have mode bits and not ACLs. Even when we were doing secu= rity >>> evaluations on Unix boxes in the 1990's they were considered insuff= iciently >>> interesting to justify the additional work to do ACLs. >>> >>> If you really want ACLs on IPC objects it would make a dandy little >>> project for a summer. I would be happy to review patches. > > Thanks. It's interesting to add ACL over IPC objects. I want to have = a try. > >> >> Or use the posix IPC mechanisms. =C2=A0The Posix shared memory has A= CL by >> using tmpfs as the backing store, and we could add similar support t= o >> Posix messages queues as they are also backed by a normal filesystem= =2E > > Christoph Hellwig, This way may be convinent. Could you give some > detailed message. :) > I only find /proc/ipc/shm file which contain the info of shm objs,and > tmpfs on /dev/shm which is empty. > >> >> Adding this support to the old SYSV IPC mechanisms would be much har= der >> as they do not fit into the file backed model we use everywhere else= at >> all. > > Just like file objects, the mode bits are implment over IPC objects > without file backed, so I think adding ACL support to IPC objects may > be somewhat reasonable :) > > Thank you all for so many solutions. > > I want to control some IPC object (shm, msg queue, semphore) can be > accessed by which named user or named group just like file objects AC= L > do. > > I studied the solution you all referred, The SELinux is powerful but > may be somewhat complicated. And I am confused with Christoph > Hellwig=E2=80=98s solution using tmpfs. Well, only posix semphores and posix share memory use tmpfs, I think, posix msg queues use "mqueue" instead. -- To unsubscribe from this list: send the line "unsubscribe linux-securit= y-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html