From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 26 Sep 2007 16:22:15 +0100 (BST) Received: from ug-out-1314.google.com ([66.249.92.174]:45316 "EHLO ug-out-1314.google.com") by ftp.linux-mips.org with ESMTP id S20029756AbXIZPWG (ORCPT ); Wed, 26 Sep 2007 16:22:06 +0100 Received: by ug-out-1314.google.com with SMTP id u2so1319527uge for ; Wed, 26 Sep 2007 08:22:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:user-agent:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding; bh=CDMDCcMvv7kXPtLR0oHFr62rQOJ2c19qPkuD4yXtZCU=; b=o04oawuWmDx2T4GxdPuob+MuUOazic4vi3M6lTOkE3fJZaayJ8tFvJ8xvKwcIPUmacHn5loaviKqQwEpEInPDrzZG7o3UDA+f3sqQQfiaeS0G+V5x+kLdaCgAaV/AI8yg0krbXEy64yoa3nH320eTVyZKPbMk2JXBYWXvZiz5aQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:user-agent:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding; b=P274ejhIgt2jeNKFOcbPoYi1hYFhnaQPYH69a1vGw4J0bOqe6Vv2pGdaSBxO7DBTpB3ZKFnVa4G6SykvsNs1ZGu2xSFe9RouiTHcpVEt1y9jzfhiQJnhDqY4C+foOCm5u2lgrrK9M4QLjdppGZmAw/dKn8CCSyNyylAeMewaU08= Received: by 10.66.239.16 with SMTP id m16mr2320700ugh.1190820126198; Wed, 26 Sep 2007 08:22:06 -0700 (PDT) Received: from ?192.168.0.1? ( [82.235.205.153]) by mx.google.com with ESMTPS id g28sm1874691fkg.2007.09.26.08.22.05 (version=TLSv1/SSLv3 cipher=RC4-MD5); Wed, 26 Sep 2007 08:22:05 -0700 (PDT) Message-ID: <46FA78AA.9050104@gmail.com> Date: Wed, 26 Sep 2007 17:20:10 +0200 From: Franck Bui-Huu User-Agent: Thunderbird 2.0.0.5 (X11/20070719) MIME-Version: 1.0 To: Ralf Baechle CC: nigel@mips.com, linux-mips Subject: Re: Useless stack randomization patch References: <46FA6846.2080704@gmail.com> <20070926150433.GA28017@linux-mips.org> In-Reply-To: <20070926150433.GA28017@linux-mips.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 16698 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: vagabon.xyz@gmail.com Precedence: bulk X-list: linux-mips Ralf Baechle wrote: > On Wed, Sep 26, 2007 at 04:10:14PM +0200, Franck Bui-Huu wrote: > I suppose we should give it a sane definition. Not sure what would be > useful, if it should be like an ASCII string with the processor type or > more corse grained like just "mips32r2", should ASEs be mentioned ... > Well before giving any sane definition, shouldn't we know why this dependency (ELF_PLATFORM/sp-randomization) exists at all... Is something like the patch below better ? Franck -- 8< -- diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 43143c5..e8713fb 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -150,6 +150,13 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, struct vm_area_struct *vma; /* + * In some cases (e.g. Hyper-Threading), we want to avoid L1 + * evictions by the processes running on the same package. One + * thing we can do is to shuffle the initial stack for them. + */ + p = arch_align_stack(p); + + /* * If this architecture has a platform capability string, copy it * to userspace. In some cases (Sparc), this info is impossible * for userspace to get any other way, in others (i386) it is @@ -159,14 +166,6 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, if (k_platform) { size_t len = strlen(k_platform) + 1; - /* - * In some cases (e.g. Hyper-Threading), we want to avoid L1 - * evictions by the processes running on the same package. One - * thing we can do is to shuffle the initial stack for them. - */ - - p = arch_align_stack(p); - u_platform = (elf_addr_t __user *)STACK_ALLOC(p, len); if (__copy_to_user(u_platform, k_platform, len)) return -EFAULT;