From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.mail.elte.hu (mx2.mail.elte.hu [157.181.151.9]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id F115CDDE19 for ; Thu, 7 May 2009 07:56:27 +1000 (EST) Date: Wed, 6 May 2009 23:54:50 +0200 From: Ingo Molnar To: Markus Gutschke =?utf-8?B?KOmhp+Wtn+WLpCk=?= Subject: Re: [PATCH 2/2] x86-64: seccomp: fix 32/64 syscall hole Message-ID: <20090506215450.GA9537@elte.hu> References: <20090228030226.C0D34FC3DA@magilla.sf.frob.com> <20090228030413.5B915FC3DA@magilla.sf.frob.com> <20090228072554.CFEA6FC3DA@magilla.sf.frob.com> <904b25810905061146ged374f2se0afd24e9e3c1f06@mail.gmail.com> <20090506212913.GC4861@elte.hu> <904b25810905061446m73c42040nfff47c9b8950bcfa@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <904b25810905061446m73c42040nfff47c9b8950bcfa@mail.gmail.com> Cc: linux-mips@linux-mips.org, x86@kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, sparclinux@vger.kernel.org, Andrew Morton , Linus Torvalds , stable@kernel.org, Roland McGrath List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , * Markus Gutschke (顧孟勤) wrote: > On Wed, May 6, 2009 at 14:29, Ingo Molnar wrote: > > That's a pretty interesting usage. What would be fallback mode you > > are using if the kernel doesnt have seccomp built in? Completely > > non-sandboxed? Or a ptrace/PTRACE_SYSCALL based sandbox? > > Ptrace has performance and/or reliability problems when used to > sandbox threaded applications due to potential race conditions > when inspecting system call arguments. We hope that we can avoid > this problem with seccomp. It is very attractive that kernel > automatically terminates any application that violates the very > well-defined constraints of the sandbox. > > In general, we are currently exploring different options based on > general availability, functionality, and complexity of > implementation. Seccomp is a good middle ground that we expect to > be able to use in the medium term to provide an acceptable > solution for a large segment of Linux users. Although the > restriction to just four unfiltered system calls is painful. Which other system calls would you like to use? Futexes might be one, for fast synchronization primitives? Ingo