diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c index c1b5906348b1..a134c41b14b3 100644 --- a/security/apparmor/apparmorfs.c +++ b/security/apparmor/apparmorfs.c @@ -2568,6 +2568,7 @@ static struct aa_sfs_entry aa_sfs_entry_attach[] = { static struct aa_sfs_entry aa_sfs_entry_domain[] = { AA_SFS_FILE_BOOLEAN("change_hat", 1), AA_SFS_FILE_BOOLEAN("change_hatv", 1), + AA_SFS_FILE_BOOLEAN("unconfined_allowed_children", 1), AA_SFS_FILE_BOOLEAN("change_onexec", 1), AA_SFS_FILE_BOOLEAN("change_profile", 1), AA_SFS_FILE_BOOLEAN("stack", 1), diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c index 1ceb25f85cb2..13c37509013b 100644 --- a/security/apparmor/domain.c +++ b/security/apparmor/domain.c @@ -1197,10 +1197,24 @@ int aa_change_hat(const char *hats[], int count, u64 token, int flags) if (task_no_new_privs(current) && !unconfined(label) && !ctx->nnp) ctx->nnp = aa_get_label(label); + /* return -EPERM when unconfined doesn't have children to avoid + * changing the traditional error code for unconfined. + */ if (unconfined(label)) { - info = "unconfined can not change_hat"; - error = -EPERM; - goto fail; + struct label_it i; + bool empty = true; + + rcu_read_lock(); + label_for_each_in_ns(i, labels_ns(label), label, profile) { + empty &= list_empty(&profile->base.profiles); + } + rcu_read_unlock(); + + if (empty) { + info = "unconfined can not change_hat"; + error = -EPERM; + goto fail; + } } if (count) {