linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Oleg Nesterov <oleg@redhat.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Aleksa Sarai <asarai@suse.com>,
	Andy Lutomirski <luto@amacapital.net>,
	Attila Fazekas <afazekas@redhat.com>, Jann Horn <jann@thejh.net>,
	Kees Cook <keescook@chromium.org>,
	Michal Hocko <mhocko@kernel.org>,
	Ulrich Obergfell <uobergfe@redhat.com>,
	linux-kernel@vger.kernel.org, linux-api@vger.kernel.org
Subject: Re: [RFC][PATCH v2 3/5] clone: Disallown CLONE_THREAD with a shared sighand_struct
Date: Wed, 5 Apr 2017 20:11:03 +0200	[thread overview]
Message-ID: <20170405181103.GA19444@redhat.com> (raw)
In-Reply-To: <87o9waep28.fsf@xmission.com>

On 04/05, Eric W. Biederman wrote:
>
> Oleg Nesterov <oleg@redhat.com> writes:
>
> I agree that changing userspace semantics is something to be very
> careful with.  But at least for purposes of discussion I think this is a
> good patch.

I agree that we need it with your approach,

but imo it would be much better to not depend on the subtle changes
like this. My 2/2 or your 1/5 are already bad enough.

> I can avoid this change but it requires moving sighand->siglock
> into signal_struct and introducing a new spinlock into sighand_struct
> to just guard the signal handlers.

Oh, this looks much, much worse to me.

Oleg.

  reply	other threads:[~2017-04-05 18:11 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20170213141452.GA30203@redhat.com>
     [not found] ` <20170224160354.GA845@redhat.com>
     [not found]   ` <87shmv6ufl.fsf@xmission.com>
     [not found]     ` <20170303173326.GA17899@redhat.com>
     [not found]       ` <20170303173326.GA17899-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-03-03 18:23         ` [PATCH 0/2] fix the traced mt-exec deadlock Eric W. Biederman
2017-03-03 18:59           ` Eric W. Biederman
     [not found]             ` <87d1dyw5iw.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-03-03 20:06               ` Eric W. Biederman
     [not found]                 ` <87tw7aunuh.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-03-03 20:11                   ` [RFC][PATCH] exec: Don't wait for ptraced threads to be reaped Eric W. Biederman
2017-03-04 17:03                     ` Oleg Nesterov
2017-03-30  8:07                       ` Eric W. Biederman
     [not found]                         ` <8760ir192p.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-01  5:11                           ` [RFC][PATCH 0/2] exec: Fixing ptrace'd mulit-threaded hang Eric W. Biederman
     [not found]                             ` <878tnkpv8h.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-01  5:14                               ` [RFC][PATCH 1/2] sighand: Count each thread group once in sighand_struct Eric W. Biederman
2017-04-01  5:16                               ` [RFC][PATCH 2/2] exec: If possible don't wait for ptraced threads to be reaped Eric W. Biederman
     [not found]                                 ` <87vaqooggs.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-02 15:35                                   ` Oleg Nesterov
     [not found]                                     ` <20170402153517.GA12637-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-04-02 18:53                                       ` Eric W. Biederman
     [not found]                                         ` <877f32k5ew.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-03 18:12                                           ` Oleg Nesterov
2017-04-03 21:04                                             ` Eric W. Biederman
2017-04-05 16:44                                               ` Oleg Nesterov
2017-04-02 15:38                               ` [RFC][PATCH 0/2] exec: Fixing ptrace'd mulit-threaded hang Oleg Nesterov
2017-04-02 22:50                               ` [RFC][PATCH v2 0/5] " Eric W. Biederman
     [not found]                                 ` <874ly6a0h1.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-02 22:51                                   ` [RFC][PATCH v2 1/5] ptrace: Don't wait in PTRACE_O_TRACEEXIT for exec or coredump Eric W. Biederman
2017-04-05 16:19                                     ` Oleg Nesterov
2017-04-02 22:51                                   ` [RFC][PATCH v2 2/5] sighand: Count each thread group once in sighand_struct Eric W. Biederman
2017-04-02 22:52                                   ` [RFC][PATCH v2 3/5] clone: Disallown CLONE_THREAD with a shared sighand_struct Eric W. Biederman
     [not found]                                     ` <87k2728lrp.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-05 16:24                                       ` Oleg Nesterov
2017-04-05 17:34                                         ` Eric W. Biederman
2017-04-05 18:11                                           ` Oleg Nesterov [this message]
2017-04-02 22:53                                   ` [RFC][PATCH v2 4/5] exec: If possible don't wait for ptraced threads to be reaped Eric W. Biederman
2017-04-05 16:15                                     ` Oleg Nesterov
2017-04-02 22:57                                   ` [RFC][PATCH v2 5/5] signal: Don't allow accessing signal_struct by old threads after exec Eric W. Biederman
     [not found]                                     ` <87zify76z9.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-05 16:18                                       ` Oleg Nesterov
     [not found]                                         ` <20170405161812.GD14536-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-04-05 18:16                                           ` Eric W. Biederman
     [not found]                                             ` <87zifu90to.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-06 15:48                                               ` Oleg Nesterov
2017-04-02 16:15                           ` [RFC][PATCH] exec: Don't wait for ptraced threads to be reaped Oleg Nesterov
     [not found]                             ` <20170402161518.GC12637-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-04-02 21:07                               ` Eric W. Biederman
     [not found]                                 ` <87inmmbjsq.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-03 18:37                                   ` Oleg Nesterov
     [not found]                                     ` <20170403183728.GB31390-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-04-03 22:49                                       ` Eric W. Biederman
2017-04-03 22:49                                       ` scope of cred_guard_mutex Eric W. Biederman
2017-04-05 16:08                                         ` Oleg Nesterov
2017-04-05 16:11                                           ` Kees Cook
2017-04-05 17:53                                           ` Eric W. Biederman
2017-04-05 18:15                                             ` Oleg Nesterov
     [not found]                                         ` <87fuhpjeco.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-04-06 15:55                                           ` Oleg Nesterov
     [not found]                                             ` <20170406155540.GC7444-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-04-07 22:07                                               ` Kees Cook
2017-09-04  3:19                                   ` [RFC][PATCH] exec: Don't wait for ptraced threads to be reaped Robert O'Callahan
     [not found]           ` <87tw7axlr0.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2017-03-04 16:54             ` [PATCH 0/2] fix the traced mt-exec deadlock Oleg Nesterov

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=20170405181103.GA19444@redhat.com \
    --to=oleg@redhat.com \
    --cc=afazekas@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=asarai@suse.com \
    --cc=ebiederm@xmission.com \
    --cc=jann@thejh.net \
    --cc=keescook@chromium.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=luto@amacapital.net \
    --cc=mhocko@kernel.org \
    --cc=uobergfe@redhat.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;
as well as URLs for NNTP newsgroup(s).