selinux: introduce permissive types

Introduce the concept of a permissive type.  A new ebitmap is introduced to
the policy database which indicates if a given type has the permissive bit
set or not.  This bit is tested for the scontext of any denial.  The bit is
meaningless on types which only appear as the target of a decision and never
the source.  A domain running with a permissive type will be allowed to
perform any action similarly to when the system is globally set permissive.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index cb3f0ce0b00a..a4fc6e6d038a 100644
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -893,12 +893,13 @@ int avc_has_perm_noaudit(u32 ssid, u32 tsid,
         denied = requested & ~(p_ae->avd.allowed);
 
         if (denied) {
-                if (selinux_enforcing || (flags & AVC_STRICT))
+                if (flags & AVC_STRICT)
                         rc = -EACCES;
+                else if (!selinux_enforcing || security_permissive_sid(ssid))
+                        avc_update_node(AVC_CALLBACK_GRANT, requested, ssid,
+                                        tsid, tclass);
                 else
-                        if (node)
-                                avc_update_node(AVC_CALLBACK_GRANT,requested,
-                                                ssid,tsid,tclass);
+                        rc = -EACCES;
         }
 
         rcu_read_unlock();