From: Oleg Nesterov <oleg@redhat.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
Gao feng <gaofeng@cn.fujitsu.com>,
Containers <containers@lists.linux-foundation.org>,
linux-fsdevel@vger.kernel.org,
Aditya Kali <adityakali@google.com>,
Andy Lutomirski <luto@amacapital.net>
Subject: Re: [REVIEW][PATCH 3/3] vfs: Fix a regression in mounting proc
Date: Wed, 27 Nov 2013 17:13:00 +0100 [thread overview]
Message-ID: <20131127161300.GA24773@redhat.com> (raw)
In-Reply-To: <87pppmzoin.fsf_-_@xmission.com>
To all: sorry for noise, I can't comment this patch.
But Eric, could you please help me to understand? I am totally confused.
So, afaics, initially (even after MS_KERNMOUNT) fs_fully_visible("proc")
should return false.
After the normal "mout -t proc none /proc/" it becomes true.
And it is still true after, say, "mount -t ramfs none /proc/sys" because
"ls -ld /proc/sys" shows ->i_nlink == 1.
However, say, "mount -t ramfs none /proc/tty/" should make
fs_fully_visible() == F, because in this case ->i_nlink == 4.
Correct?
If yes, could you explain what this "!CAP_SYS_ADMIN && !fs_fully_visible"
check actually tries to prevent and why?
Thanks,
Oleg.
next prev parent reply other threads:[~2013-11-27 16:11 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-15 16:41 Regression wrt mounting /proc in user namespace in 3.13 Daniel P. Berrange
[not found] ` <20131115164123.GN28794-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2013-11-16 16:48 ` Serge E. Hallyn
[not found] ` <20131116164840.GA4441-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-17 3:06 ` Serge E. Hallyn
[not found] ` <20131117030653.GA7670-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-18 3:19 ` Serge E. Hallyn
[not found] ` <20131118031932.GA17621-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-18 4:52 ` Gao feng
[not found] ` <52899D09.5080202-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
2013-11-18 14:08 ` Serge E. Hallyn
[not found] ` <20131118140830.GA22075-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-18 18:01 ` Serge E. Hallyn
[not found] ` <20131118180134.GA24156-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-19 1:51 ` Eric W. Biederman
[not found] ` <87k3g5gnuv.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-19 3:47 ` Serge E. Hallyn
2013-11-26 18:10 ` Serge E. Hallyn
[not found] ` <20131126181043.GA25492-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-27 0:14 ` [REVIEW][PATCH 0/3] userns fixes for v3.13-rc1 Eric W. Biederman
[not found] ` <87siui1z1g.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 0:16 ` [REVIEW][PATCH 1/3] vfs: In d_path don't call d_dname on a mount point Eric W. Biederman
2013-11-27 1:58 ` Serge E. Hallyn
[not found] ` <8738mi1yya.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 1:58 ` Serge E. Hallyn
2013-11-30 6:15 ` Al Viro
[not found] ` <20131130061525.GY10323-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
2013-11-30 17:02 ` Al Viro
[not found] ` <20131130170226.GZ10323-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
2013-11-30 21:51 ` Eric W. Biederman
[not found] ` <87a9glh838.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-30 22:43 ` Al Viro
[not found] ` <20131130224340.GA10323-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
2013-12-02 7:29 ` Al Viro
2014-01-17 3:29 ` Eric W. Biederman
[not found] ` <874n53gub7.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2014-01-17 8:39 ` Al Viro
[not found] ` <20140117083901.GA10323-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
2014-02-07 2:21 ` [PATCH 0/4] d_dname cleanups Eric W. Biederman
[not found] ` <87iosrhdc0.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2014-02-07 2:23 ` [PATCH 1/4] perfmon: Use d_alloc_pseudo like all of the d_dname callers Eric W. Biederman
2014-02-07 2:23 ` [PATCH 2/4] vfs: Simply when d_alloc_dname is called Eric W. Biederman
2014-02-07 2:24 ` [PATCH 3/4] vfs: Move the call of d_op->d_dname from d_path to prepend_path Eric W. Biederman
2014-02-07 2:24 ` [PATCH 4/4] vfs: Call d_dname from dentry_path Eric W. Biederman
2014-01-17 3:29 ` [REVIEW][PATCH 1/3] vfs: In d_path don't call d_dname on a mount point Eric W. Biederman
2013-12-01 5:09 ` Al Viro
2013-12-01 6:15 ` [REVIEW][PATCH 1/3] vfs: In d_path don't call d_dname on a mountpoint Tetsuo Handa
[not found] ` <20131201050930.GB10323-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
2013-12-01 6:15 ` Tetsuo Handa
2013-12-02 5:43 ` [REVIEW][PATCH 1/3] vfs: In d_path don't call d_dname on a mount point NeilBrown
2013-12-02 5:43 ` NeilBrown
[not found] ` <20131202164359.4f4f2c94-wvvUuzkyo1EYVZTmpyfIwg@public.gmane.org>
2013-12-02 16:23 ` J.Bruce Fields
2013-12-02 16:23 ` J.Bruce Fields
2013-12-02 16:23 ` J.Bruce Fields
2013-11-27 0:16 ` [REVIEW][PATCH 2/3] fork: Allow CLONE_PARENT after setns(CLONE_NEWPID) Eric W. Biederman
2013-11-27 0:16 ` Eric W. Biederman
[not found] ` <87vbzezojq.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 1:58 ` Serge E. Hallyn
2013-11-27 0:17 ` [REVIEW][PATCH 3/3] vfs: Fix a regression in mounting proc Eric W. Biederman
[not found] ` <87pppmzoin.fsf_-_-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 0:21 ` Andy Lutomirski
[not found] ` <CALCETrVp78EfzY3Oa-LV1Hm8A4Y35apehcxrxdyrzvTb5sp=pA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-11-27 0:36 ` Eric W. Biederman
2013-11-27 2:00 ` Serge E. Hallyn
2013-11-27 3:19 ` Gao feng
2013-11-27 5:00 ` Eric W. Biederman
[not found] ` <529564AA.8050100-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
2013-11-27 5:00 ` Eric W. Biederman
2013-11-27 16:13 ` Oleg Nesterov
2013-11-27 16:13 ` Oleg Nesterov [this message]
[not found] ` <20131127161300.GA24773-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2013-11-27 16:29 ` Serge E. Hallyn
[not found] ` <20131127162928.GB7358-7LNsyQBKDXoIagZqoN9o3w@public.gmane.org>
2013-11-27 18:09 ` Oleg Nesterov
2013-11-27 16:41 ` Andy Lutomirski
[not found] ` <CALCETrXFnw63=JoEaQxM+Opj+kCXSL=9XppymzGKhLzOnp3WaQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-11-27 18:10 ` Oleg Nesterov
2013-11-27 18:51 ` Eric W. Biederman
[not found] ` <871u21oeyr.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 19:47 ` Oleg Nesterov
2013-11-27 19:47 ` Oleg Nesterov
[not found] ` <20131127194722.GA32673-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2013-11-27 19:52 ` Eric W. Biederman
2013-11-27 19:52 ` Eric W. Biederman
[not found] ` <87iovdmxl7.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 20:01 ` Oleg Nesterov
2013-11-27 20:07 ` Eric W. Biederman
2013-11-27 20:41 ` Andy Lutomirski
[not found] ` <CALCETrUwjK7iLMMJaCvKUbBwEqV58oXY4dWzTGJohYgg4DwjWQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-11-29 14:56 ` Serge E. Hallyn
[not found] ` <87wqjtlic3.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2013-11-27 20:41 ` Andy Lutomirski
2013-11-29 19:53 ` Oleg Nesterov
2013-12-13 22:07 ` Richard Weinberger
[not found] ` <20131129195327.GA12974-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2013-12-13 22:07 ` Richard Weinberger
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=20131127161300.GA24773@redhat.com \
--to=oleg@redhat.com \
--cc=adityakali@google.com \
--cc=containers@lists.linux-foundation.org \
--cc=ebiederm@xmission.com \
--cc=gaofeng@cn.fujitsu.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=luto@amacapital.net \
--cc=serge@hallyn.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.