From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Carstens Subject: Re: linux-next: manual merge of the audit tree with the security tree Date: Sat, 25 Jun 2016 09:28:42 +0200 Message-ID: <20160625072842.GA3303@osiris> References: <20160623141814.5512ffd1@canb.auug.org.au> <20160623060113.GA3866@osiris> <20160624054131.GA3940@osiris> <20160624152046.GB3940@osiris> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:58246 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751133AbcFYH2t (ORCPT ); Sat, 25 Jun 2016 03:28:49 -0400 Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5P7ShSR127952 for ; Sat, 25 Jun 2016 03:28:48 -0400 Received: from e06smtp12.uk.ibm.com (e06smtp12.uk.ibm.com [195.75.94.108]) by mx0a-001b2d01.pphosted.com with ESMTP id 23ryh8f9da-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Sat, 25 Jun 2016 03:28:48 -0400 Received: from localhost by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sat, 25 Jun 2016 08:28:47 +0100 Content-Disposition: inline In-Reply-To: Sender: linux-next-owner@vger.kernel.org List-ID: To: Paul Moore Cc: Stephen Rothwell , James Morris , linux-next@vger.kernel.org, linux-kernel@vger.kernel.org, Kees Cook , Martin Schwidefsky On Fri, Jun 24, 2016 at 12:20:52PM -0400, Paul Moore wrote: > > I'm a bit concerned about user space pointers passed as argument for compat > > tasks. These need to mask out 33 instead of 32 bits. This is of course > > system call specific and I don't know enough about audit to tell if it > > could be a problem. > > From a practical point of view I'm not sure how much of an impact that > will have as it is unlikely anyone will be doing anything useful with > those pointer values; for example, you aren't going to be inspecting a > process' memory space using just the audit log. Also, at the very > least we aren't removing any information, just adding in an extra bit > of potential junk. Anyone who does care about user space pointers in > the audit log, should have all the information the need to drop the > high bit. > > Does that sound reasonable? Yes, it does. If there should be problems because of the one extra bit that potentially contains garbage we still can look for a way to fix this. Thanks!