public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: Vasiliy Kulikov <segoon@openwall.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-kernel@vger.kernel.org, viro@zeniv.linux.org.uk,
	rientjes@google.com, wilsons@start.ca, security@kernel.org,
	kernel-hardening@lists.openwall.com
Subject: Re: [PATCH v2] proc: fix a race in do_io_accounting()
Date: Tue, 5 Jul 2011 14:13:01 -0700	[thread overview]
Message-ID: <20110705141301.0d3594e0.akpm@linux-foundation.org> (raw)
In-Reply-To: <20110704201339.GA5645@albatros>

<wakes up>

On Tue, 5 Jul 2011 00:13:39 +0400
Vasiliy Kulikov <segoon@openwall.com> wrote:

> There is a ptrace_may_access() check in do_io_accounting() to prevent
> gathering information of setuid'ed and similar binaries.  However, there
> is a race against execve().  Holding task->signal->cred_guard_mutex
> while gathering the information should protect against the race.
> 
> The order of locking is similar to the one inside of
> ptrace_attach(): first goes cred_guard_mutex, then lock_task_sighand().
> 
> v2 - use mutex_lock_killable() instead of mutex_lock().
> 
> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
> Cc: stable@kernel.org

If a patch is to be backported into -stable then its changelog had
better explain why such a thing is needed.  This one doesn't.

Please provide a full description of the conseuqences of the bug.  One
which will permit the -stable maintainers to understand why they're
merging the patch, and one which will help distribution maintainers
decide whether they want to merge it as well.


  reply	other threads:[~2011-07-05 21:13 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-07-03 10:39 [PATCH] proc: fix a race in do_io_accounting() Vasiliy Kulikov
2011-07-03 19:24 ` Linus Torvalds
2011-07-03 20:01   ` Vasiliy Kulikov
2011-07-04 20:13   ` [PATCH v2] " Vasiliy Kulikov
2011-07-05 21:13     ` Andrew Morton [this message]
2011-07-06 16:34       ` [PATCH v3] " Vasiliy Kulikov
2011-07-15  6:38         ` Vasiliy Kulikov
2011-07-15 16:14           ` Linus Torvalds

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=20110705141301.0d3594e0.akpm@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=kernel-hardening@lists.openwall.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=rientjes@google.com \
    --cc=security@kernel.org \
    --cc=segoon@openwall.com \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@zeniv.linux.org.uk \
    --cc=wilsons@start.ca \
    /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