From mboxrd@z Thu Jan 1 00:00:00 1970 Reply-To: kernel-hardening@lists.openwall.com Sender: Vasiliy Kulikov Date: Mon, 20 Jun 2011 19:44:29 +0400 From: Vasiliy Kulikov Message-ID: <20110620154429.GA12879@albatros> References: <20110617171152.GA1389@albatros> <4DFF5795.9080609@redhat.com> <20110620150001.GF12469@mail.hallyn.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110620150001.GF12469@mail.hallyn.com> Subject: [kernel-hardening] Re: [RFC v2] security: intoduce ptrace_task_may_access_current To: Serge Hallyn Cc: Eric Paris , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, apparmor@lists.ubuntu.com, "selinux@tycho.nsa.gov Stephen Smalley" , James Morris , Eric Paris , John Johansen , kernel-hardening@lists.openwall.com, serge@hallyn.com List-ID: On Mon, Jun 20, 2011 at 10:00 -0500, Serge Hallyn wrote: > > >diff --git a/kernel/capability.c b/kernel/capability.c > > >index 283c529..bc9b07f 100644 > > >--- a/kernel/capability.c > > >+++ b/kernel/capability.c > > >@@ -356,6 +356,30 @@ bool capable(int cap) > > > } > > > EXPORT_SYMBOL(capable); > > > > > >+bool task_capable(struct task_struct *task, int cap) > > >+{ > > >+ return ns_task_capable(task,&init_user_ns, cap); > > >+} > > >+EXPORT_SYMBOL(task_capable); > > > > Why do we keep adding things like task_capable? Can't we just stop > > adding non-lsm functions and just call the right LSM functions from > > now on? This is my original comments mostly directed at Serge. I'm > > to the point where I want to NAK anything new in kernel/capability.c > > (and yes, I know i'm guilty in the paste) > > > > >+bool ns_task_capable(struct task_struct *task, struct user_namespace *ns, int cap) > > Can you just use has_ns_capability() at the places where you wanted to > use your new ns_task_capable()? It won't set PF_SUPERPRIV, but you > can't set that on another task anyway IIRC. has_ns_capability() doesn't touch LSMs, but ns_task_capable() uses security_task_capable() which uses LSMs. Actually, I'm a bit confused in sense of what capable functions should be used in specific cases. Where we need to inform LSM and where not. I don't want to bypass LSMs where it should not do it otherwise. In the patch I've copied alredy existing behaviour leaving LSM iteraction as-is. Thanks, -- Vasiliy Kulikov http://www.openwall.com - bringing security into open computing environments