[PATCH bpf-next v2 1/9] bpf, lsm: Add disabled BPF LSM hook list
Xu Kuohai
xukuohai at huaweicloud.com
Fri Jul 19 11:00:51 UTC 2024
From: Xu Kuohai <xukuohai at huawei.com>
Add a disabled hooks list for BPF LSM. progs being attached to the
listed hooks will be rejected by the verifier.
Suggested-by: KP Singh <kpsingh at kernel.org>
Signed-off-by: Xu Kuohai <xukuohai at huawei.com>
---
kernel/bpf/bpf_lsm.c | 31 +++++++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)
diff --git a/kernel/bpf/bpf_lsm.c b/kernel/bpf/bpf_lsm.c
index 08a338e1f231..1f596ad6257c 100644
--- a/kernel/bpf/bpf_lsm.c
+++ b/kernel/bpf/bpf_lsm.c
@@ -36,6 +36,24 @@ 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 +115,24 @@ 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;
}
--
2.30.2
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