Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754707AbaFXTfD (ORCPT ); Tue, 24 Jun 2014 15:35:03 -0400 Received: from mail-la0-f42.google.com ([209.85.215.42]:47704 "EHLO mail-la0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753122AbaFXTe6 (ORCPT ); Tue, 24 Jun 2014 15:34:58 -0400 MIME-Version: 1.0 In-Reply-To: <20140624193055.GA4482@redhat.com> References: <1403560693-21809-1-git-send-email-keescook@chromium.org> <1403560693-21809-5-git-send-email-keescook@chromium.org> <20140624191815.GA3623@redhat.com> <20140624193055.GA4482@redhat.com> From: Andy Lutomirski Date: Tue, 24 Jun 2014 12:34:36 -0700 Message-ID: Subject: Re: [PATCH v7 4/9] seccomp: move no_new_privs into seccomp To: Oleg Nesterov Cc: Kees Cook , "linux-kernel@vger.kernel.org" , Alexei Starovoitov , "Michael Kerrisk (man-pages)" , Andrew Morton , Daniel Borkmann , Will Drewry , Julien Tinnes , David Drysdale , Linux API , X86 ML , "linux-arm-kernel@lists.infradead.org" , linux-mips@linux-mips.org, linux-arch , LSM List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 24, 2014 at 12:30 PM, Oleg Nesterov wrote: > On 06/24, Andy Lutomirski wrote: >> >> On Tue, Jun 24, 2014 at 12:18 PM, Oleg Nesterov wrote: >> >> >> >> -struct seccomp { }; >> >> +struct seccomp { >> >> + unsigned long flags; >> >> +}; >> > >> > A bit messy ;) >> > >> > I am wondering if we can simply do >> > >> > static inline bool current_no_new_privs(void) >> > { >> > if (current->no_new_privs) >> > return true; >> > >> > #ifdef CONFIG_SECCOMP >> > if (test_thread_flag(TIF_SECCOMP)) >> > return true; >> > #endif >> >> Nope -- privileged users can enable seccomp w/o nnp. > > Indeed, I am stupid. > > Still it would be nice to cleanup this somehow. The new member is only > used as a previous ->no_new_privs, just it is long to allow the concurent > set/get. Logically it doesn't even belong to seccomp{}. We could add an unsigned long atomic flags field to task_struct. Grr. Why isn't there an unsigned *int* atomic bitmask type? Even u64 would be better. unsigned long is useless. > > Oleg. > -- Andy Lutomirski AMA Capital Management, LLC -- 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/