From 5bf7a60b8e70969f65c961d7e2c4eb40eb2c664d Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Thu, 27 Sep 2018 14:37:30 -0700 Subject: [PATCH] bpf: permit CGROUP_DEVICE programs accessing helper bpf_get_current_cgroup_id() Currently, helper bpf_get_current_cgroup_id() is not permitted for CGROUP_DEVICE type of programs. If the helper is used in such cases, the verifier will log the following error: 0: (bf) r6 = r1 1: (69) r7 = *(u16 *)(r6 +0) 2: (85) call bpf_get_current_cgroup_id#80 unknown func bpf_get_current_cgroup_id#80 The bpf_get_current_cgroup_id() is useful for CGROUP_DEVICE type of programs in order to customize action based on cgroup id. This patch added such a support. Cc: Roman Gushchin Signed-off-by: Yonghong Song Acked-by: Alexei Starovoitov Acked-by: Roman Gushchin Signed-off-by: Daniel Borkmann --- kernel/bpf/cgroup.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 6a7d931..549f6fb 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -677,6 +677,8 @@ cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_get_current_uid_gid_proto; case BPF_FUNC_get_local_storage: return &bpf_get_local_storage_proto; + case BPF_FUNC_get_current_cgroup_id: + return &bpf_get_current_cgroup_id_proto; case BPF_FUNC_trace_printk: if (capable(CAP_SYS_ADMIN)) return bpf_get_trace_printk_proto(); -- 2.7.4