From 9823c25b3ea894315f3c9c8802166f3d311511a5 Mon Sep 17 00:00:00 2001
From: Simon McVittie <simon.mcvittie@collabora.co.uk>
Date: Mon, 16 Feb 2015 15:29:03 +0000
Subject: [PATCH 12/31] fix: bus_apparmor_pre_init: distinguish between OOM and
 AppArmor not enabled

---
 bus/apparmor.c | 22 +++++++++++++++++++---
 bus/main.c     |  2 +-
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/bus/apparmor.c b/bus/apparmor.c
index d171833..1f09b6c 100644
--- a/bus/apparmor.c
+++ b/bus/apparmor.c
@@ -83,14 +83,20 @@ bus_apparmor_audit_init (void)
 #endif /* HAVE_LIBAUDIT */
 }
 
+/*
+ * Return TRUE on successful check, FALSE on OOM.
+ * Set *is_supported to whether AA has D-Bus features.
+ */
 static dbus_bool_t
-_bus_apparmor_aa_supports_dbus (void)
+_bus_apparmor_detect_aa_dbus_support (dbus_bool_t *is_supported)
 {
   int mask_file;
   DBusString aa_dbus;
   char *aa_securityfs = NULL;
   dbus_bool_t retval = FALSE;
 
+  *is_supported = FALSE;
+
   if (!_dbus_string_init (&aa_dbus))
     return FALSE;
 
@@ -110,10 +116,12 @@ _bus_apparmor_aa_supports_dbus (void)
                     O_RDONLY | O_CLOEXEC);
   if (mask_file != -1)
     {
-      retval = TRUE;
+      *is_supported = TRUE;
       close (mask_file);
     }
 
+  retval = TRUE;
+
 out:
   free (aa_securityfs);
   _dbus_string_free (&aa_dbus);
@@ -124,12 +132,20 @@ out:
 
 /**
  * Do early initialization; determine whether AppArmor is enabled.
+ * Return TRUE on successful check (whether AppArmor is actually
+ * enabled or not) or FALSE on OOM.
  */
 dbus_bool_t
 bus_apparmor_pre_init (void)
 {
 #ifdef HAVE_APPARMOR
-  apparmor_enabled = (aa_is_enabled () && _bus_apparmor_aa_supports_dbus ());
+  apparmor_enabled = FALSE;
+
+  if (!aa_is_enabled ())
+    return TRUE;
+
+  if (!_bus_apparmor_detect_aa_dbus_support (&apparmor_enabled))
+    return FALSE;
 #endif
 
   return TRUE;
diff --git a/bus/main.c b/bus/main.c
index 1575195..b48f03f 100644
--- a/bus/main.c
+++ b/bus/main.c
@@ -617,7 +617,7 @@ main (int argc, char **argv)
 
   if (!bus_apparmor_pre_init ())
     {
-      _dbus_warn ("AppArmor pre-initialization failed\n");
+      _dbus_warn ("AppArmor pre-initialization failed: out of memory\n");
       exit (1);
     }
 
-- 
2.1.4