Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757528AbYFJTM6 (ORCPT ); Tue, 10 Jun 2008 15:12:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753833AbYFJTMu (ORCPT ); Tue, 10 Jun 2008 15:12:50 -0400 Received: from e2.ny.us.ibm.com ([32.97.182.142]:36313 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752984AbYFJTMt (ORCPT ); Tue, 10 Jun 2008 15:12:49 -0400 Date: Tue, 10 Jun 2008 14:12:41 -0500 From: "Serge E. Hallyn" To: "Andrew G. Morgan" Cc: "Serge E. Hallyn" , Andrew Morton , Dmitry Adamushko , Linus Torvalds , linux-kernel Subject: Re: [PATCH] bugfix: was Re: [ linus-git ] prctl(PR_SET_KEEPCAPS, ...) is broken for some configs, e.g. CONFIG_SECURITY_SELINUX Message-ID: <20080610191241.GA17311@us.ibm.com> References: <1212932321.4675.9.camel@earth> <484BF662.9070100@kernel.org> <20080608110630.08a45cc6.akpm@linux-foundation.org> <484C5E84.2020307@kernel.org> <20080608163926.56f1be3d.akpm@linux-foundation.org> <20080609171741.GA13403@us.ibm.com> <484E0280.2050305@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <484E0280.2050305@kernel.org> User-Agent: Mutt/1.5.17+20080114 (2008-01-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3294 Lines: 109 Quoting Andrew G. Morgan (morgan@kernel.org): > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > I agree. Short term, here is a patch to add dummy support for KEEPCAPS. > > Cheers > > Andrew > > Serge E. Hallyn wrote: > |>> I fear that nothing will happen, and we'll end up wasting a lot of > |> peoples' time sending hey-why-did-my-dhcp-break reports. > | > | If we decide to get rid of dummy long-term, then it's far less > | distasteful to have it lie and claim the keepcaps worked in the > | meantime. > | > | So for 2.6.26 we could have dummy lie, then plan to make capabilities > | the default for 2.6.27? > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.2.6 (GNU/Linux) > > iD8DBQFITgKA+bHCR3gb8jsRAiQYAJ47VnlBq2GSvLQv40tymjybLhNAtQCgya8G > YZQN/5w1uq+X2MYv1x4T4D4= > =NhwX > -----END PGP SIGNATURE----- > From be19a4716c97c5aaf4c9721eeccfab2d44897ce2 Mon Sep 17 00:00:00 2001 > From: Andrew G. Morgan > Date: Mon, 9 Jun 2008 21:22:18 -0700 > Subject: [PATCH] Add (back) dummy support for KEEPCAPS. > > See: http://bugzilla.kernel.org/show_bug.cgi?id=10748 > > Signed-off-by: Andrew G. Morgan Thanks, Andrew. Just one question inline. Nevertheless, Acked-by: Serge Hallyn Dmitry, does this fix the problem for you? (Not sure why I'm feeling queasy about this given that find . -name "*.c" -exec "grep" "-Hn" "issecure" "{}" \; returns only hits in security/commoncap.c...) > --- > security/dummy.c | 24 +++++++++++++++++++++++- > 1 files changed, 23 insertions(+), 1 deletions(-) > > diff --git a/security/dummy.c b/security/dummy.c > index f50c6c3..b891688 100644 > --- a/security/dummy.c > +++ b/security/dummy.c > @@ -27,6 +27,8 @@ > #include > #include > #include > +#include > +#include > > static int dummy_ptrace (struct task_struct *parent, struct task_struct *child) > { > @@ -607,7 +609,27 @@ static int dummy_task_kill (struct task_struct *p, struct siginfo *info, > static int dummy_task_prctl (int option, unsigned long arg2, unsigned long arg3, > unsigned long arg4, unsigned long arg5, long *rc_p) > { > - return 0; > + switch (option) { > + case PR_CAPBSET_READ: > + *rc_p = (cap_valid(arg2) ? 1 : -EINVAL); > + break; > + case PR_GET_KEEPCAPS: > + *rc_p = issecure(SECURE_KEEP_CAPS); > + break; > + case PR_SET_KEEPCAPS: > + if (arg2 > 1) > + *rc_p = -EINVAL; > + else if (arg2) > + current->securebits |= issecure_mask(SECURE_KEEP_CAPS); > + else > + current->securebits &= > + ~issecure_mask(SECURE_KEEP_CAPS); In these last two conditions, don't you need to set *rc_p? Oh, or my kernel tree may be out of date, as I seem to recall a recent patch initializing error to 0 in sys_prctl(), so this wouldn't technically be a problem? Still would seem correct... > + break; > + default: > + return 0; > + } > + > + return 1; > } > > static void dummy_task_reparent_to_init (struct task_struct *p) > -- > 1.5.3.7 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/