bpf: Enable generic kfuncs for BPF_CGROUP_* programs

These kfuncs are enabled even in BPF_PROG_TYPE_TRACING, so they
should be safe also in BPF_CGROUP_* programs.
Since all BPF_CGROUP_* programs share the same hook,
call register_btf_kfunc_id_set() only once.

In enum btf_kfunc_hook, rename BTF_KFUNC_HOOK_CGROUP_SKB to a more
generic BTF_KFUNC_HOOK_CGROUP, since it's used for all the cgroup
related program types.

Signed-off-by: Matteo Croce <teknoraver@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240819162805.78235-2-technoboy85@gmail.com

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index bfb0d89..b12db39 100644 (file)
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -212,7 +212,7 @@ enum btf_kfunc_hook {
        BTF_KFUNC_HOOK_TRACING,
        BTF_KFUNC_HOOK_SYSCALL,
        BTF_KFUNC_HOOK_FMODRET,
-       BTF_KFUNC_HOOK_CGROUP_SKB,
+       BTF_KFUNC_HOOK_CGROUP,
        BTF_KFUNC_HOOK_SCHED_ACT,
        BTF_KFUNC_HOOK_SK_SKB,
        BTF_KFUNC_HOOK_SOCKET_FILTER,
@@ -8307,8 +8307,12 @@ static int bpf_prog_type_to_kfunc_hook(enum bpf_prog_type prog_type)
        case BPF_PROG_TYPE_SYSCALL:
                return BTF_KFUNC_HOOK_SYSCALL;
        case BPF_PROG_TYPE_CGROUP_SKB:
+       case BPF_PROG_TYPE_CGROUP_SOCK:
+       case BPF_PROG_TYPE_CGROUP_DEVICE:
        case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
-               return BTF_KFUNC_HOOK_CGROUP_SKB;
+       case BPF_PROG_TYPE_CGROUP_SOCKOPT:
+       case BPF_PROG_TYPE_CGROUP_SYSCTL:
+               return BTF_KFUNC_HOOK_CGROUP;
        case BPF_PROG_TYPE_SCHED_ACT:
                return BTF_KFUNC_HOOK_SCHED_ACT;
        case BPF_PROG_TYPE_SK_SKB:

diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index d02ae32..26b9649 100644 (file)
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -3052,6 +3052,7 @@ static int __init kfunc_init(void)
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &generic_kfunc_set);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &generic_kfunc_set);
        ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &generic_kfunc_set);
+       ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_CGROUP_SKB, &generic_kfunc_set);
        ret = ret ?: register_btf_id_dtor_kfuncs(generic_dtors,
                                                  ARRAY_SIZE(generic_dtors),
                                                  THIS_MODULE);