lkml.org 
[lkml]   [2016]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 1/2] cgroup: apply common ancestor cgroup.procs restriction in cgroupv1
On Tue, May 03, 2016 at 12:01:20AM +1000, Aleksa Sarai wrote:
> The common ancestor restriction for moving tasks between cgroups (the
> process moving the task must have the right to write to cgroup.procs in
> both the destination and common ancestor cgroup) only applied for
> cgroupv2 (cgroups in the default hierarchy). This meant that there was a
> different policy for unprivileged users in the different cgroup
> hierarchies.
>
> Update cgroup_procs_write_permission() to apply the cgroup.procs
> restriction regardless of the cgroup root of the destination cgroup.
> However, if the task doesn't have any association with the destination
> hierarchy, there's no permission check to be done. In addition, if the
> destination cgroup is a descendant of the task's current cgroup then
> there are no further permission checks. This is important for
> unprivileged processes creating subtrees.

So, you can't apply a new restriction like this retro-actively to
cgroup v1 hierarchies.

Thanks.

--
tejun

\
 
 \ /
  Last update: 2016-05-02 18:21    [W:0.138 / U:0.172 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site