From: Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
Cc: Linux Containers
<containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [REVIEW][PATCH 3/5] pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD
Date: Sun, 8 Sep 2013 19:00:01 +0200 [thread overview]
Message-ID: <20130908170001.GA1835@redhat.com> (raw)
In-Reply-To: <87a9k0yrvu.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
Sorry for delay, vacation.
On 08/29, Eric W. Biederman wrote:
>
> I goofed when I made unshare(CLONE_NEWPID) only work in a
> single-threaded process. There is no need for that requirement and in
> fact I analyzied things right for setns. The hard requirement
> is for tasks that share a VM to all be in the pid namespace and
> we properly prevent that in do_fork.
Yes, agreed, with the current meaning of ->pid_ns unshare(NEWPID)
looks safe even if the caller is multi-threaded... and this matches
pidns_install() which doesn't require single-threaded.
Oleg.
WARNING: multiple messages have this Message-ID (diff)
From: Oleg Nesterov <oleg@redhat.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Linux Containers <containers@lists.linux-foundation.org>,
"Serge E. Hallyn" <serge@hallyn.com>,
linux-kernel@vger.kernel.org
Subject: Re: [REVIEW][PATCH 3/5] pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD
Date: Sun, 8 Sep 2013 19:00:01 +0200 [thread overview]
Message-ID: <20130908170001.GA1835@redhat.com> (raw)
In-Reply-To: <87a9k0yrvu.fsf@xmission.com>
Sorry for delay, vacation.
On 08/29, Eric W. Biederman wrote:
>
> I goofed when I made unshare(CLONE_NEWPID) only work in a
> single-threaded process. There is no need for that requirement and in
> fact I analyzied things right for setns. The hard requirement
> is for tasks that share a VM to all be in the pid namespace and
> we properly prevent that in do_fork.
Yes, agreed, with the current meaning of ->pid_ns unshare(NEWPID)
looks safe even if the caller is multi-threaded... and this matches
pidns_install() which doesn't require single-threaded.
Oleg.
next prev parent reply other threads:[~2013-09-08 17:00 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-29 23:52 [REVIEW][PATCH 0/5] A couple of lingering namespace patches Eric W. Biederman
2013-08-29 23:52 ` Eric W. Biederman
[not found] ` <87ob8gys0d.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-29 23:53 ` [REVIEW][PATCH 1/5] namespaces: Simplify copy_namespaces so it is clear what is going on Eric W. Biederman
2013-08-29 23:53 ` Eric W. Biederman
[not found] ` <87ioyoyryr.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-30 16:10 ` Serge E. Hallyn
2013-08-30 16:10 ` Serge E. Hallyn
2013-08-29 23:54 ` [REVIEW][PATCH 2/5] userns: Allow PR_CAPBSET_DROP in a user namespace Eric W. Biederman
2013-08-29 23:54 ` Eric W. Biederman
[not found] ` <87eh9cyrxj.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-30 1:15 ` Serge E. Hallyn
2013-08-30 1:15 ` Serge E. Hallyn
2013-08-29 23:55 ` [REVIEW][PATCH 3/5] pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD Eric W. Biederman
2013-08-29 23:55 ` Eric W. Biederman
[not found] ` <87a9k0yrvu.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-30 16:38 ` Serge E. Hallyn
2013-08-30 16:38 ` Serge E. Hallyn
[not found] ` <20130830163805.GB18857-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-08-30 23:49 ` Eric W. Biederman
2013-08-30 23:49 ` Eric W. Biederman
[not found] ` <87ppsuviwb.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-31 5:31 ` Serge E. Hallyn
2013-08-31 5:31 ` Serge E. Hallyn
2013-09-08 17:00 ` Oleg Nesterov [this message]
2013-09-08 17:00 ` Oleg Nesterov
2013-08-29 23:55 ` [REVIEW][PATCH 4/5] capabilities: allow nice if we are privileged Eric W. Biederman
2013-08-29 23:55 ` Eric W. Biederman
2013-08-29 23:56 ` [REVIEW][PATCH 5/5] userns: Kill nsown_capable it makes the wrong thing easy Eric W. Biederman
2013-08-29 23:56 ` Eric W. Biederman
2013-08-30 1:14 ` Serge E. Hallyn
[not found] ` <871u5cyrst.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-08-30 1:14 ` Serge E. Hallyn
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