# Re: Potential issues (security and otherwise) with the current cgroup-bpf API

- From: Andy Lutomirski \<luto@amacapital.net\>
- Date: 2016-12-20 05:26:46 
- List: netdev
- Page: https://ratatoskr.run/netdev/2016/12/4898153
- Thread: https://ratatoskr.run/linux-api/2016/12/4897252/t.md

```text
On Mon, Dec 19, 2016 at 8:51 PM, Alexei Starovoitov
[ref] wrote:
> On Mon, Dec 19, 2016 at 05:40:53PM -0800, Andy Lutomirski wrote:
>>
>> By the way, even if Alexei is right, the BPF_PROG_DETACH API doesn't
>> even take a reference to a BPF program as an argument.  What is it
>> supposed to do if this mechanism ever gets extended?
>
> we just add another field to that anonymous union just like
> we did for other commands and everything is backwards compatible.
> It's the basics of bpf syscall that we've been relying on for some
> time now and it worked just fine.

And what happens if you don't specify that member and two programs are attached?

--Andy
```