From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965867AbYD1Pto (ORCPT ); Mon, 28 Apr 2008 11:49:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S935627AbYD1Pnf (ORCPT ); Mon, 28 Apr 2008 11:43:35 -0400 Received: from saraswathi.solana.com ([198.99.130.12]:55725 "EHLO saraswathi.solana.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936280AbYD1Pnc (ORCPT ); Mon, 28 Apr 2008 11:43:32 -0400 Date: Mon, 28 Apr 2008 11:42:40 -0400 From: Jeff Dike To: WANG Cong Cc: akpm@osdl.org, linux-kernel@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net Subject: Re: [PATCH 9/19] UML - Tidy ptrace interface Message-ID: <20080428154240.GD7334@c2.user-mode-linux.org> References: <20080425175610.GA11188@c2.user-mode-linux.org> <20080426.173538.195417245.xiyou.wangcong@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080426.173538.195417245.xiyou.wangcong@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Apr 26, 2008 at 05:35:38PM +0800, WANG Cong wrote: > From: Jeff Dike > Date: Fri, 25 Apr 2008 13:56:10 -0400 > > Tidy the ptrace interface code. Removed a bunch of unused macros. > > Started converting register sets from arrays of longs to structures. > > Could you please explain a bit why do this? I think long arrary is OK. It's wrong on x86_64. There, FRAME_SIZE is 168 - #define FRAME_SIZE and SS is the last register defined - #define SS 160 but there are a number of registers beyond that in the user_regs_struct: unsigned long ss; unsigned long fs_base; unsigned long gs_base; unsigned long ds; unsigned long es; unsigned long fs; unsigned long gs; The effect of GETREGS into a long[FRAME_SIZE] will be stack corruption. Jeff -- Work email - jdike at linux dot intel dot com