From: serge.hallyn@ubuntu.com
To: linux-kernel@vger.kernel.org
Cc: adityakali@google.com, tj@kernel.org, linux-api@vger.kernel.org,
containers@lists.linux-foundation.org, cgroups@vger.kernel.org,
lxc-devel@lists.linuxcontainers.org, akpm@linux-foundation.org,
ebiederm@xmission.com, gregkh@linuxfoundation.org,
lizefan@huawei.com, hannes@cmpxchg.org,
Serge Hallyn <serge.hallyn@ubuntu.com>
Subject: [PATCH 7/7] Add FS_USERNS_FLAG to cgroup fs
Date: Mon, 7 Dec 2015 17:06:22 -0600 [thread overview]
Message-ID: <1449529582-4075-8-git-send-email-serge.hallyn@ubuntu.com> (raw)
In-Reply-To: <1449529582-4075-1-git-send-email-serge.hallyn@ubuntu.com>
From: Serge Hallyn <serge.hallyn@ubuntu.com>
allowing root in a non-init user namespace to mount it. This should
now be safe, because
1. non-init-root cannot mount a previously unbound subsystem
2. the task doing the mount must be privileged with respect to the
user namespace owning the cgroup namespace
3. the mounted subsystem will have its current cgroup as the root dentry.
the permissions will be unchanged, so tasks will receive no new
privilege over the cgroups which they did not have on the original
mounts.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
---
kernel/cgroup.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 09cd718..5419ef7 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2228,12 +2228,14 @@ static struct file_system_type cgroup_fs_type = {
.name = "cgroup",
.mount = cgroup_mount,
.kill_sb = cgroup_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
static struct file_system_type cgroup2_fs_type = {
.name = "cgroup2",
.mount = cgroup_mount,
.kill_sb = cgroup_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
char * __must_check
--
1.7.9.5
next prev parent reply other threads:[~2015-12-07 23:07 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-07 23:06 CGroup Namespaces (v6) serge.hallyn
2015-12-07 23:06 ` [PATCH 1/7] kernfs: Add API to generate relative kernfs path serge.hallyn
2015-12-08 11:51 ` Greg KH
2015-12-09 1:17 ` Serge E. Hallyn
2015-12-08 15:52 ` Tejun Heo
2015-12-08 16:46 ` Serge E. Hallyn
2015-12-08 18:45 ` Serge E. Hallyn
2015-12-07 23:06 ` [PATCH 2/7] sched: new clone flag CLONE_NEWCGROUP for cgroup namespace serge.hallyn
2015-12-07 23:06 ` [PATCH 3/7] cgroup: introduce cgroup namespaces serge.hallyn
2015-12-08 16:04 ` Tejun Heo
2015-12-08 19:34 ` Serge E. Hallyn
2015-12-08 19:46 ` Tejun Heo
2015-12-08 19:47 ` Serge E. Hallyn
2015-12-07 23:06 ` [PATCH 4/7] cgroup: cgroup namespace setns support serge.hallyn
2015-12-07 23:06 ` [PATCH 5/7] cgroup: mount cgroupns-root when inside non-init cgroupns serge.hallyn
2015-12-08 16:20 ` Tejun Heo
2015-12-08 16:48 ` Serge E. Hallyn
2015-12-08 23:21 ` Serge E. Hallyn
2015-12-09 15:48 ` Tejun Heo
2015-12-07 23:06 ` [PATCH 6/7] cgroup: Add documentation for cgroup namespaces serge.hallyn
2015-12-08 16:22 ` Tejun Heo
2015-12-07 23:06 ` serge.hallyn [this message]
2015-12-08 10:10 ` CGroup Namespaces (v6) Alban Crequy
2015-12-08 15:22 ` Serge E. Hallyn
-- strict thread matches above, loose matches on Subject: below --
2015-11-27 20:52 CGroup Namespaces (v5) serge.hallyn
2015-11-27 20:52 ` [PATCH 7/7] Add FS_USERNS_FLAG to cgroup fs serge.hallyn
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=1449529582-4075-8-git-send-email-serge.hallyn@ubuntu.com \
--to=serge.hallyn@ubuntu.com \
--cc=adityakali@google.com \
--cc=akpm@linux-foundation.org \
--cc=cgroups@vger.kernel.org \
--cc=containers@lists.linux-foundation.org \
--cc=ebiederm@xmission.com \
--cc=gregkh@linuxfoundation.org \
--cc=hannes@cmpxchg.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lizefan@huawei.com \
--cc=lxc-devel@lists.linuxcontainers.org \
--cc=tj@kernel.org \
/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).