From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750873AbWF2IPg (ORCPT ); Thu, 29 Jun 2006 04:15:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751758AbWF2IPg (ORCPT ); Thu, 29 Jun 2006 04:15:36 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:63435 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1750873AbWF2IPf (ORCPT ); Thu, 29 Jun 2006 04:15:35 -0400 Subject: Re: make PROT_WRITE imply PROT_READ From: Arjan van de Ven To: Ulrich Drepper Cc: Pavel Machek , Jason Baron , akpm@osdl.org, linux-kernel@vger.kernel.org In-Reply-To: References: <449B42B3.6010908@shaw.ca> <1151071581.3204.14.camel@laptopd505.fenrus.org> <1151072280.3204.17.camel@laptopd505.fenrus.org> <20060627095632.GA22666@elf.ucw.cz> Content-Type: text/plain Date: Thu, 29 Jun 2006 10:15:29 +0200 Message-Id: <1151568930.3122.0.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2006-06-28 at 09:43 -0700, Ulrich Drepper wrote: > On 6/27/06, Pavel Machek wrote: > > Usability for "normal" C applications is probably not too high... so > > why not work around it in glibc, if at all? > > Because it wouldn't affect all b inaries. Existing code could still > cause the problem. Also, there are other callers of the syscalls > (direct, other libcs, etc). The only reliable way to get rid of this > problem is to enforce it in the kernel. Since the kernel cannot make > sense of this setting in all situations it is IMO even necessary since > you really don't want to have anything as unstable as this code. the thing is.. you can say EXACTLY the same about PROT_EXEC.. not all processors support enforcing that.. so should we just always imply PROT_EXEC as well?