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| author | Alexei Starovoitov <ast@fb.com> | 2017-02-11 07:28:24 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-02-13 05:52:19 +0300 |
| commit | 7f677633379b4abb3281cdbe7e7006f049305c03 (patch) | |
| tree | 1e5e662e792467d09f8a4ebf5b96b2baa333ae25 /include/linux/bpf-cgroup.h | |
| parent | e722af6391949e8851310441bb0cec157d25611d (diff) | |
| download | linux-7f677633379b4abb3281cdbe7e7006f049305c03.tar.xz | |
bpf: introduce BPF_F_ALLOW_OVERRIDE flag
If BPF_F_ALLOW_OVERRIDE flag is used in BPF_PROG_ATTACH command
to the given cgroup the descendent cgroup will be able to override
effective bpf program that was inherited from this cgroup.
By default it's not passed, therefore override is disallowed.
Examples:
1.
prog X attached to /A with default
prog Y fails to attach to /A/B and /A/B/C
Everything under /A runs prog X
2.
prog X attached to /A with allow_override.
prog Y fails to attach to /A/B with default (non-override)
prog M attached to /A/B with allow_override.
Everything under /A/B runs prog M only.
3.
prog X attached to /A with allow_override.
prog Y fails to attach to /A with default.
The user has to detach first to switch the mode.
In the future this behavior may be extended with a chain of
non-overridable programs.
Also fix the bug where detach from cgroup where nothing is attached
was not throwing error. Return ENOENT in such case.
Add several testcases and adjust libbpf.
Fixes: 3007098494be ("cgroup: add support for eBPF programs")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/bpf-cgroup.h')
| -rw-r--r-- | include/linux/bpf-cgroup.h | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h index 92bc89ae7e20..c970a25d2a49 100644 --- a/include/linux/bpf-cgroup.h +++ b/include/linux/bpf-cgroup.h @@ -21,20 +21,19 @@ struct cgroup_bpf { */ struct bpf_prog *prog[MAX_BPF_ATTACH_TYPE]; struct bpf_prog __rcu *effective[MAX_BPF_ATTACH_TYPE]; + bool disallow_override[MAX_BPF_ATTACH_TYPE]; }; void cgroup_bpf_put(struct cgroup *cgrp); void cgroup_bpf_inherit(struct cgroup *cgrp, struct cgroup *parent); -void __cgroup_bpf_update(struct cgroup *cgrp, - struct cgroup *parent, - struct bpf_prog *prog, - enum bpf_attach_type type); +int __cgroup_bpf_update(struct cgroup *cgrp, struct cgroup *parent, + struct bpf_prog *prog, enum bpf_attach_type type, + bool overridable); /* Wrapper for __cgroup_bpf_update() protected by cgroup_mutex */ -void cgroup_bpf_update(struct cgroup *cgrp, - struct bpf_prog *prog, - enum bpf_attach_type type); +int cgroup_bpf_update(struct cgroup *cgrp, struct bpf_prog *prog, + enum bpf_attach_type type, bool overridable); int __cgroup_bpf_run_filter_skb(struct sock *sk, struct sk_buff *skb, |