apparmor: allow restricting unprivileged change_profile

unprivileged unconfined can use change_profile to alter the confinement
set by the mac admin.

Allow restricting unprivileged unconfined by still allowing change_profile
but stacking the change against unconfined. This allows unconfined to
still apply system policy but allows the task to enter the new confinement.

If unprivileged unconfined is required a sysctl is provided to switch
to the previous behavior.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index bcfe8b9cb4c1..518576ae3cfb 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1798,6 +1798,13 @@ static struct ctl_table apparmor_sysctl_table[] = {
 		.mode           = 0600,
 		.proc_handler   = apparmor_dointvec,
 	},
+	{
+		.procname       = "apparmor_restrict_unprivileged_unconfined",
+		.data           = &aa_unprivileged_unconfined_restricted,
+		.maxlen         = sizeof(int),
+		.mode           = 0600,
+		.proc_handler   = apparmor_dointvec,
+	},
 
 	{ }
 };