netdev - Re: [PATCH net-next v2 2/2] bpf: Remove the capability check for cgroup skb eBPF program

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Message-ID: <20170601234235.iwu55crijtxuq5mp@ast-mbp>
Date:   Thu, 1 Jun 2017 16:42:36 -0700
From:   Alexei Starovoitov <alexei.starovoitov@...il.com>
To:     Chenbo Feng <chenbofeng.kernel@...il.com>
Cc:     netdev@...r.kernel.org, David Miller <davem@...emloft.net>,
        Lorenzo Colitti <lorenzo@...gle.com>,
        Chenbo Feng <fengc@...gle.com>
Subject: Re: [PATCH net-next v2 2/2] bpf: Remove the capability check for
 cgroup skb eBPF program

On Wed, May 31, 2017 at 06:16:00PM -0700, Chenbo Feng wrote:
> From: Chenbo Feng <fengc@...gle.com>
> 
> Currently loading a cgroup skb eBPF program require a CAP_SYS_ADMIN
> capability while attaching the program to a cgroup only requires the
> user have CAP_NET_ADMIN privilege. We can escape the capability
> check when load the program just like socket filter program to make
> the capability requirement consistent.
> 
> Change since v1:
> Change the code style in order to be compliant with checkpatch.pl
> preference
> 
> Signed-off-by: Chenbo Feng <fengc@...gle.com>

as far as I can see they're indeed the same as socket filters, so
Acked-by: Alexei Starovoitov <ast@...nel.org>

but I don't quite understand how it helps, since as you said
attaching such unpriv fd to cgroup still requires root.
Do you have more patches to follow?