diff options
Diffstat (limited to 'kernel/bpf/bpf_lsm.c')
-rw-r--r-- | kernel/bpf/bpf_lsm.c | 65 |
1 files changed, 62 insertions, 3 deletions
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c index 08a338e1f231..6292ac5f9bd1 100644 --- a/kernel/bpf/bpf_lsm.c +++ b/kernel/bpf/bpf_lsm.c @@ -11,7 +11,6 @@ #include <linux/lsm_hooks.h> #include <linux/bpf_lsm.h> #include <linux/kallsyms.h> -#include <linux/bpf_verifier.h> #include <net/bpf_sk_storage.h> #include <linux/bpf_local_storage.h> #include <linux/btf_ids.h> @@ -36,6 +35,24 @@ BTF_SET_START(bpf_lsm_hooks) #undef LSM_HOOK BTF_SET_END(bpf_lsm_hooks) +BTF_SET_START(bpf_lsm_disabled_hooks) +BTF_ID(func, bpf_lsm_vm_enough_memory) +BTF_ID(func, bpf_lsm_inode_need_killpriv) +BTF_ID(func, bpf_lsm_inode_getsecurity) +BTF_ID(func, bpf_lsm_inode_listsecurity) +BTF_ID(func, bpf_lsm_inode_copy_up_xattr) +BTF_ID(func, bpf_lsm_getselfattr) +BTF_ID(func, bpf_lsm_getprocattr) +BTF_ID(func, bpf_lsm_setprocattr) +#ifdef CONFIG_KEYS +BTF_ID(func, bpf_lsm_key_getsecurity) +#endif +#ifdef CONFIG_AUDIT +BTF_ID(func, bpf_lsm_audit_rule_match) +#endif +BTF_ID(func, bpf_lsm_ismaclabel) +BTF_SET_END(bpf_lsm_disabled_hooks) + /* List of LSM hooks that should operate on 'current' cgroup regardless * of function signature. */ @@ -97,15 +114,24 @@ void bpf_lsm_find_cgroup_shim(const struct bpf_prog *prog, int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog, const struct bpf_prog *prog) { + u32 btf_id = prog->aux->attach_btf_id; + const char *func_name = prog->aux->attach_func_name; + if (!prog->gpl_compatible) { bpf_log(vlog, "LSM programs must have a GPL compatible license\n"); return -EINVAL; } - if (!btf_id_set_contains(&bpf_lsm_hooks, prog->aux->attach_btf_id)) { + if (btf_id_set_contains(&bpf_lsm_disabled_hooks, btf_id)) { + bpf_log(vlog, "attach_btf_id %u points to disabled hook %s\n", + btf_id, func_name); + return -EINVAL; + } + + if (!btf_id_set_contains(&bpf_lsm_hooks, btf_id)) { bpf_log(vlog, "attach_btf_id %u points to wrong type name %s\n", - prog->aux->attach_btf_id, prog->aux->attach_func_name); + btf_id, func_name); return -EINVAL; } @@ -390,3 +416,36 @@ const struct bpf_verifier_ops lsm_verifier_ops = { .get_func_proto = bpf_lsm_func_proto, .is_valid_access = btf_ctx_access, }; + +/* hooks return 0 or 1 */ +BTF_SET_START(bool_lsm_hooks) +#ifdef CONFIG_SECURITY_NETWORK_XFRM +BTF_ID(func, bpf_lsm_xfrm_state_pol_flow_match) +#endif +#ifdef CONFIG_AUDIT +BTF_ID(func, bpf_lsm_audit_rule_known) +#endif +BTF_ID(func, bpf_lsm_inode_xattr_skipcap) +BTF_SET_END(bool_lsm_hooks) + +int bpf_lsm_get_retval_range(const struct bpf_prog *prog, + struct bpf_retval_range *retval_range) +{ + /* no return value range for void hooks */ + if (!prog->aux->attach_func_proto->type) + return -EINVAL; + + if (btf_id_set_contains(&bool_lsm_hooks, prog->aux->attach_btf_id)) { + retval_range->minval = 0; + retval_range->maxval = 1; + } else { + /* All other available LSM hooks, except task_prctl, return 0 + * on success and negative error code on failure. + * To keep things simple, we only allow bpf progs to return 0 + * or negative errno for task_prctl too. + */ + retval_range->minval = -MAX_ERRNO; + retval_range->maxval = 0; + } + return 0; +} |