Commit 34ea38ca authored Jun 04, 2018 by Yonghong Song Committed by Daniel Borkmann Jun 04, 2018

bpf: guard bpf_get_current_cgroup_id() with CONFIG_CGROUPS



Commit bf6fa2c8 ("bpf: implement bpf_get_current_cgroup_id()
helper") introduced a new helper bpf_get_current_cgroup_id().
The helper has a dependency on CONFIG_CGROUPS.

When CONFIG_CGROUPS is not defined, using the helper will result
the following verifier error:
  kernel subsystem misconfigured func bpf_get_current_cgroup_id#80
which is hard for users to interpret.
Guarding the reference to bpf_get_current_cgroup_id_proto with
CONFIG_CGROUPS will result in below better message:
  unknown func bpf_get_current_cgroup_id#80

Fixes: bf6fa2c8 ("bpf: implement bpf_get_current_cgroup_id() helper")
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

parent 64995362

kernel/trace/bpf_trace.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -564,8 +564,10 @@ tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
		return &bpf_get_prandom_u32_proto;
		case BPF_FUNC_probe_read_str:
		return &bpf_probe_read_str_proto;
		#ifdef CONFIG_CGROUPS
		case BPF_FUNC_get_current_cgroup_id:
		return &bpf_get_current_cgroup_id_proto;
		#endif
		default:
		return NULL;
		}

Admin message