diff options
Diffstat (limited to 'kernel/bpf/bpf_lsm.c')
| -rw-r--r-- | kernel/bpf/bpf_lsm.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index c1351df9f7ee..d469b7f3deef 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -16,6 +16,7 @@ #include <linux/bpf_local_storage.h> #include <linux/btf_ids.h> #include <linux/ima.h> +#include <linux/bpf-cgroup.h> /* For every LSM hook that allows attachment of BPF programs, declare a nop * function where a BPF program can be attached. @@ -35,6 +36,57 @@ BTF_SET_START(bpf_lsm_hooks) #undef LSM_HOOK BTF_SET_END(bpf_lsm_hooks) +/* List of LSM hooks that should operate on 'current' cgroup regardless + * of function signature. + */ +BTF_SET_START(bpf_lsm_current_hooks) +/* operate on freshly allocated sk without any cgroup association */ +BTF_ID(func, bpf_lsm_sk_alloc_security) +BTF_ID(func, bpf_lsm_sk_free_security) +BTF_SET_END(bpf_lsm_current_hooks) + +/* List of LSM hooks that trigger while the socket is properly locked. + */ +BTF_SET_START(bpf_lsm_locked_sockopt_hooks) +BTF_ID(func, bpf_lsm_socket_sock_rcv_skb) +BTF_ID(func, bpf_lsm_sock_graft) +BTF_ID(func, bpf_lsm_inet_csk_clone) +BTF_ID(func, bpf_lsm_inet_conn_established) +BTF_SET_END(bpf_lsm_locked_sockopt_hooks) + +/* List of LSM hooks that trigger while the socket is _not_ locked, + * but it's ok to call bpf_{g,s}etsockopt because the socket is still + * in the early init phase. + */ +BTF_SET_START(bpf_lsm_unlocked_sockopt_hooks) +BTF_ID(func, bpf_lsm_socket_post_create) +BTF_ID(func, bpf_lsm_socket_socketpair) +BTF_SET_END(bpf_lsm_unlocked_sockopt_hooks) + +void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog, + bpf_func_t *bpf_func) +{ + const struct btf_param *args; + + if (btf_type_vlen(prog->aux->attach_func_proto) < 1 || + btf_id_set_contains(&bpf_lsm_current_hooks, + prog->aux->attach_btf_id)) { + *bpf_func = __cgroup_bpf_run_lsm_current; + return; + } + + args = btf_params(prog->aux->attach_func_proto); + +#ifdef CONFIG_NET + if (args[0].type == btf_sock_ids[BTF_SOCK_TYPE_SOCKET]) + *bpf_func = __cgroup_bpf_run_lsm_socket; + else if (args[0].type == btf_sock_ids[BTF_SOCK_TYPE_SOCK]) + *bpf_func = __cgroup_bpf_run_lsm_sock; + else +#endif + *bpf_func = __cgroup_bpf_run_lsm_current; +} + int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, const struct bpf_prog *prog) { @@ -158,6 +210,35 @@ bpf_lsm_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return prog->aux->sleepable ? &bpf_ima_file_hash_proto : NULL; case BPF_FUNC_get_attach_cookie: return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto : NULL; + case BPF_FUNC_get_local_storage: + return prog->expected_attach_type == BPF_LSM_CGROUP ? + &bpf_get_local_storage_proto : NULL; + case BPF_FUNC_set_retval: + return prog->expected_attach_type == BPF_LSM_CGROUP ? + &bpf_set_retval_proto : NULL; + case BPF_FUNC_get_retval: + return prog->expected_attach_type == BPF_LSM_CGROUP ? + &bpf_get_retval_proto : NULL; + case BPF_FUNC_setsockopt: + if (prog->expected_attach_type != BPF_LSM_CGROUP) + return NULL; + if (btf_id_set_contains(&bpf_lsm_locked_sockopt_hooks, + prog->aux->attach_btf_id)) + return &bpf_sk_setsockopt_proto; + if (btf_id_set_contains(&bpf_lsm_unlocked_sockopt_hooks, + prog->aux->attach_btf_id)) + return &bpf_unlocked_sk_setsockopt_proto; + return NULL; + case BPF_FUNC_getsockopt: + if (prog->expected_attach_type != BPF_LSM_CGROUP) + return NULL; + if (btf_id_set_contains(&bpf_lsm_locked_sockopt_hooks, + prog->aux->attach_btf_id)) + return &bpf_sk_getsockopt_proto; + if (btf_id_set_contains(&bpf_lsm_unlocked_sockopt_hooks, + prog->aux->attach_btf_id)) + return &bpf_unlocked_sk_getsockopt_proto; + return NULL; default: return tracing_prog_func_proto(func_id, prog); } |