public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Oleg Nesterov <oleg@tv-sign.ru>
To: Jay Lan <jlan@engr.sgi.com>
Cc: Andrew Morton <akpm@osdl.org>,
	Shailabh Nagar <nagar@watson.ibm.com>,
	Balbir Singh <balbir@in.ibm.com>, Jay Lan <jlan@sgi.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] xacct_add_tsk: fix pure theoretical ->mm use-after-free
Date: Mon, 30 Oct 2006 23:41:25 +0300	[thread overview]
Message-ID: <20061030204125.GB677@oleg> (raw)
In-Reply-To: <454649CE.80804@engr.sgi.com>

On 10/30, Jay Lan wrote:
>
> Oleg Nesterov wrote:
> > Paranoid fix. The task can free its ->mm after the 'if (p->mm)' check.
> 
> Why this change is necessary? This routine is indirectly invoked by
> taskstats_exit_send() routine called inside do_exit():

Not only, please note

	taskstats_user_cmd(TASKSTATS_CMD_ATTR_PID)->fill_pid()->xacct_add_tsk()

path. This tsk is not 'current', it was found by find_task_by_pid(), and
it may exit at any time.

Oleg.


  reply	other threads:[~2006-10-30 20:41 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-10-29 18:58 [PATCH] xacct_add_tsk: fix pure theoretical ->mm use-after-free Oleg Nesterov
2006-10-30 18:51 ` Jay Lan
2006-10-30 20:41   ` Oleg Nesterov [this message]
2006-10-31  3:08     ` Jay Lan

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=20061030204125.GB677@oleg \
    --to=oleg@tv-sign.ru \
    --cc=akpm@osdl.org \
    --cc=balbir@in.ibm.com \
    --cc=jlan@engr.sgi.com \
    --cc=jlan@sgi.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nagar@watson.ibm.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