# Re: \[PATCH 4/7\] netprio\_cgroup: limit the maximum css-\>id to USHRT\_MAX

- From: Daniel Wagner \<hidden\>
- Date: 2015-11-20 09:18:25 
- List: netdev
- Page: https://ratatoskr.run/netdev/2015/11/4624921
- Thread: https://ratatoskr.run/netdev/2015/11/4624449/t.md

```text
On 11/19/2015 07:52 PM, Tejun Heo wrote:
> netprio builds per-netdev contiguous priomap array which is indexed by
> css->id.  The array is allocated using kzalloc() effectively limiting
> the maximum ID supported to some thousand range.  This patch caps the
> maximum supported css->id to USHRT_MAX which should be way above what
> is actually useable.
> 
> This allows reducing sock->sk_cgrp_prioidx to u16 from u32.  The freed
> up part will be used to overload the cgroup related fields.
> sock->sk_cgrp_prioidx's position is swapped with sk_mark so that the
> two cgroup related fields are adjacent.
> 
> Signed-off-by: Tejun Heo <tj@kernel.org>
> Cc: Daniel Borkmann <daniel@iogearbox.net>
> Cc: Daniel Wagner <redacted>

Acked-by: Daniel Wagner <redacted>
```