[RFC][PATCH 0/3] Kernel memory accounting container (v2)

[KAMEZAWA Hiroyuki]

On Thu, 13 Sep 2007 13:11:35 +0400
Pavel Emelyanov <xemul at openvz.org> wrote:

> First of all - why do we need this kind of control. The major
> "pros" is that kernel memory control protects the system
> from DoS attacks by processes that live in container. As our
> experience shows many exploits simply do not work in the
> container with limited kernel memory.
> 
> I can split the kernel memory container into 4 parts:
> 
> 1. kmalloc-ed objects control
> 2. vmalloc-ed objects control
> 3. buddy allocated pages control
> 4. kmem_cache_alloc-ed objects control
> 
<snip>
> To play with it, one need to mount the container file system
> with -o kmem and then mark some caches as accountable via
> /sys/slab/<cache_name>/cache_account.
> 
Hmm, how can we know "How many kmem will we need ?" in precise per-object
style ? Is this useful ? 

Following kind of limitation of user friendly params is bad ?

 - # of file handles
 - # of tasks
 - # of sockets/ connections / packets
 - # of posix IPC related things
 - and other sources of DoS.

Thanks,
-Kame