linux-um archives
 help / color / mirror / Atom feed
From: Jeff Dike <jdike@addtoit.com>
To: WANG Cong <xiyou.wangcong@gmail.com>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org,
	user-mode-linux-devel@lists.sourceforge.net
Subject: Re: [uml-devel] [PATCH 9/19] UML - Tidy ptrace interface
Date: Mon, 28 Apr 2008 11:42:40 -0400	[thread overview]
Message-ID: <20080428154240.GD7334@c2.user-mode-linux.org> (raw)
In-Reply-To: <20080426.173538.195417245.xiyou.wangcong@gmail.com>

On Sat, Apr 26, 2008 at 05:35:38PM +0800, WANG Cong wrote:
> From: Jeff Dike <jdike@addtoit.com>
> 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

-------------------------------------------------------------------------
This SF.net email is sponsored by the 2008 JavaOne(SM) Conference 
Don't miss this year's exciting event. There's still time to save $100. 
Use priority code J8TL2D2. 
http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone
_______________________________________________
User-mode-linux-devel mailing list
User-mode-linux-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel

  reply	other threads:[~2008-04-28 15:42 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-25 17:56 [uml-devel] [PATCH 9/19] UML - Tidy ptrace interface Jeff Dike
2008-04-26  9:35 ` WANG Cong
2008-04-28 15:42   ` Jeff Dike [this message]
2008-04-29  8:14     ` WANG Cong

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20080428154240.GD7334@c2.user-mode-linux.org \
    --to=jdike@addtoit.com \
    --cc=akpm@osdl.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=user-mode-linux-devel@lists.sourceforge.net \
    --cc=xiyou.wangcong@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox