From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751197AbWGAX1U (ORCPT ); Sat, 1 Jul 2006 19:27:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751211AbWGAX1U (ORCPT ); Sat, 1 Jul 2006 19:27:20 -0400 Received: from terminus.zytor.com ([192.83.249.54]:23190 "EHLO terminus.zytor.com") by vger.kernel.org with ESMTP id S1751197AbWGAX1U (ORCPT ); Sat, 1 Jul 2006 19:27:20 -0400 Message-ID: <44A704A4.8080402@zytor.com> Date: Sat, 01 Jul 2006 16:26:28 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 1.5.0.4 (X11/20060614) MIME-Version: 1.0 To: "H. Peter Anvin" CC: Sam Ravnborg , Miles Lane , Arjan van de Ven , Andrew Morton , LKML Subject: Re: 2.6.17-mm5 -- Busted toolchain? -- usr/klibc/exec_l.c:59: undefined reference to `__stack_chk_fail' References: <1151788673.3195.58.camel@laptopd505.fenrus.org> <1151789342.3195.60.camel@laptopd505.fenrus.org> <20060701230635.GA19114@mars.ravnborg.org> <44A7011B.6000702@zytor.com> In-Reply-To: <44A7011B.6000702@zytor.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org H. Peter Anvin wrote: > Sam Ravnborg wrote: >> >> For klibc you need to patch scripts/Kbuild.klibc >> >> Appending it to KLIBCWARNFLAGS seems the right place. > > KLIBCREQFLAGS, rather. > >> Do you know from what gcc version we can start using >> -fno-stack-protector? > > Isn't there a macro to test if gcc supports a specific option already? > > Either way, I can also add __stack_chk_fail() as an alias for abort(), > for people who actually want the feature. > I looked at it again, and it looks like gcc depends on the TLS ABI in order to pick the value of the cookie. That makes it a potentially lot more cantankerous option; I would like to be able to support stack-smash checking in klibc, but if it means implementing TLS on all architectures, then that would really defeat the purpose (and we should add -fno-stack-protector to KLIBCREQFLAGS.) Arjan: I see a few stack-protector-related have your name on it, do you have any details on implementation constraints for this across architectures? -hpa