On 2022/09/28 4:53, Casey Schaufler wrote: > @@ -483,6 +491,16 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count, > { > int i; > > + /* > + * A security module may call security_add_hooks() more > + * than once. Landlock is one such case. > + */ > + if (lsm_id == 0 || lsm_idlist[lsm_id - 1] != lsmid) > + lsm_idlist[lsm_id++] = lsmid; > + > + if (lsm_id > LSMID_ENTRIES) > + panic("%s Too many LSMs registered.\n", __func__); I'm not happy with LSMID_ENTRIES. This is a way towards forever forbidding LKM-based LSMs. I'm fine with using UAPI-visible constants for switching /proc/ files. But TOMOYO does not need such constant because TOMOYO does not use /proc/ files. Also, lsm_self_attr() will be limited for LSM modules which use /proc/ files, and therefore I think prctl() will be already there. > + > for (i = 0; i < count; i++) { > hooks[i].lsmid = lsmid; > hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);