Re: [PATCH] capabilities: audit capability use

From: Tejun Heo
Date: Tue Jul 12 2016 - 10:59:46 EST


On Mon, Jul 11, 2016 at 07:47:44PM +0000, Topi Miettinen wrote:
> It's really critical to be able to associate a task in the logs to
> cgroups which were valid that time. Or can we infer somehow what cgroups

When is "that time"? Without logging all operations, this is
meaningless.

> a task was taking part, long time after task exit? Perhaps task cgroup
> membership changes and changes in available cgroups should be logged too?
>
> Some kind of cgroup IDs could be logged instead of long paths. Then
> these IDs should be reliably resolvable to paths offline somehow.

I don't think that's doable. That pretty much requires the kernel to
remember paths of all past cgroups.

> How usual migrations between cgroups are? Why would a task ever move
> from (say) systemd/system.slice/smartd.service to anywhere else?

In most cases, they won't move once set up initially but that's not
the point of audit subsystem. Logging this once one exit isn't gonna
help anything for auditing the system.

Thanks.

--
tejun