On Thu, Jun 06, 2019 at 09:39:35PM +0200, Daniel Borkmann wrote: > On 06/06/2019 09:08 PM, Roman Gushchin wrote: > > On Thu, Jun 06, 2019 at 11:59:11AM -0700, Roman Gushchin wrote: > >> Currently bpf_get_current_cgroup_id() is not supported for > >> CGROUP_SKB programs. An attempt to load such a program generates an > >> error like this: > >> libbpf: > >> 0: (b7) r6 = 0 > >> ... > >> 8: (63) *(u32 *)(r10 -28) = r6 > >> 9: (85) call bpf_get_current_cgroup_id#80 > >> unknown func bpf_get_current_cgroup_id#80 > >> > >> There are no particular reasons for denying it, > >> and we have some use cases where it might be useful. > > > > Ah, sorry, it's not so simple, as we probably need to take > > the cgroup pointer from the socket, not from current. > > > > So the implementation of the helper should be different > > for this type of programs. > > > > So I wonder if it's better to introduce a new helper > > bpf_get_sock_cgroup_id()? > > > > What do you think? > > We do have bpf_skb_cgroup_id(), did you give that a try? It also isn't supported for CGROUP_SKB, but other than that looks exactly what I need. Thank you for pointing at it!
