Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756505Ab3HYPE3 (ORCPT ); Sun, 25 Aug 2013 11:04:29 -0400 Received: from cantor2.suse.de ([195.135.220.15]:47743 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756383Ab3HYPE1 convert rfc822-to-8bit (ORCPT ); Sun, 25 Aug 2013 11:04:27 -0400 Subject: Re: [PATCH 2/2] ppc: kvm: use anon_inode_getfd() with O_CLOEXEC flag Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: text/plain; charset=us-ascii From: Alexander Graf In-Reply-To: Date: Sun, 25 Aug 2013 16:04:21 +0100 Cc: Gleb Natapov , Paolo Bonzini , Benjamin Herrenschmidt , Paul Mackerras , Alex Williamson , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8BIT Message-Id: <3557EF65-4327-4DAE-999A-B0EE13C433F5@suse.de> References: To: Yann Droneaud X-Mailer: Apple Mail (2.1278) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1176 Lines: 29 On 24.08.2013, at 21:14, Yann Droneaud wrote: > KVM uses anon_inode_get() to allocate file descriptors as part > of some of its ioctls. But those ioctls are lacking a flag argument > allowing userspace to choose options for the newly opened file descriptor. > > In such case it's advised to use O_CLOEXEC by default so that > userspace is allowed to choose, without race, if the file descriptor > is going to be inherited across exec(). > > This patch set O_CLOEXEC flag on all file descriptors created > with anon_inode_getfd() to not leak file descriptors across exec(). > > Signed-off-by: Yann Droneaud > Link: http://lkml.kernel.org/r/cover.1377372576.git.ydroneaud@opteya.com Reviewed-by: Alexander Graf Would it make sense to simply inherit the O_CLOEXEC flag from the parent kvm fd instead? That would give user space the power to keep fds across exec() if it wants to. Alex -- 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/