Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759058AbYBGKnx (ORCPT ); Thu, 7 Feb 2008 05:43:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755102AbYBGKnp (ORCPT ); Thu, 7 Feb 2008 05:43:45 -0500 Received: from vervifontaine.sonytel.be ([80.88.33.193]:38666 "EHLO vervifontaine.sonycom.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754390AbYBGKno (ORCPT ); Thu, 7 Feb 2008 05:43:44 -0500 Date: Thu, 7 Feb 2008 11:43:43 +0100 (CET) From: Geert Uytterhoeven To: Ingo Molnar cc: Jiri Kosina , Andrew Morton , Arjan van de Ven , Randy Dunlap , Hugh Dickins , Pavel Machek , linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] ASLR: add possibility for more fine-grained tweaking In-Reply-To: <20080207103231.GD16735@elte.hu> Message-ID: References: <20080206134959.GA25689@elte.hu> <20080207103231.GD16735@elte.hu> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="-584349381-1261992843-1202381023=:11914" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2712 Lines: 67 This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. ---584349381-1261992843-1202381023=:11914 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT On Thu, 7 Feb 2008, Ingo Molnar wrote: > * Geert Uytterhoeven wrote: > > On Wed, 6 Feb 2008, Ingo Molnar wrote: > > > @@ -541,6 +541,18 @@ config ELF_CORE > > > help > > > Enable support for generating core dumps. Disabling saves about 4k. > > > > > > +config COMPAT_BRK > > > + bool "Disable heap randomization" > > > + default y > > > + help > > > + Randomizing heap placement makes heap exploits harder, but it > > > + also breaks ancient binaries (including anything libc5 based). > > > + This option changes the bootup default to heap randomization > > > + disabled, and can be overriden runtime by setting > > > + /proc/sys/kernel/randomize_va_space to 2. > > > + > > > + On non-ancient distros (post-2000 ones) Y is usually a safe choice. > > > > Somehow my belly feeling tells me something is wrong with this description... > > > > Ah, a negative option (Y -> disable). So Y is always safe. > > > > `non-ancient distros' really means `recent distros', and if you have > > one, then _N_ should be a safe choice, too? > > yeah, you are right :-) I'll fix this. > > btw., "non-ancient distros" does not just mean "recent distros", it > really means "just about any distro you picked up in the past 10 years". > You'd have to go out on a limb to find something historic (or keep > copying /lib/libc5 binaries to new distros like Pavel did) to still have > this particular libc5 assumption/breakage. [ Or at least so i hope =B-)] Bummer, I guess my good old m68k recovery ramdisk is affected ;-) With kind regards, Geert Uytterhoeven Software Architect Sony Network and Software Technology Center Europe The Corporate Village · Da Vincilaan 7-D1 · B-1935 Zaventem · Belgium Phone: +32 (0)2 700 8453 Fax: +32 (0)2 700 8622 E-mail: Geert.Uytterhoeven@sonycom.com Internet: http://www.sony-europe.com/ Sony Network and Software Technology Center Europe A division of Sony Service Centre (Europe) N.V. Registered office: Technologielaan 7 · B-1840 Londerzeel · Belgium VAT BE 0413.825.160 · RPR Brussels Fortis Bank Zaventem · Swift GEBABEBB08A · IBAN BE39001382358619 ---584349381-1261992843-1202381023=:11914-- -- 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/