Config option to set a default LSM
The LSM currently requires setting a kernel parameter at boot to select
a specific LSM. This adds a config option that allows specifying a default
LSM that is used unless overridden with the security= kernel parameter.
If the the config option is not set the current behavior of first LSM
to register is used.
Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/security.c b/security/security.c
index 684d5ee..aad71b2 100644
--- a/security/security.c
+++ b/security/security.c
@@ -19,7 +19,8 @@
#include <linux/ima.h>
/* Boot-time LSM user choice */
-static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1];
+static __initdata char chosen_lsm[SECURITY_NAME_MAX + 1] =
+ CONFIG_DEFAULT_SECURITY;
/* things that live in capability.c */
extern struct security_operations default_security_ops;
@@ -80,8 +81,10 @@
*
* Return true if:
* -The passed LSM is the one chosen by user at boot time,
- * -or user didn't specify a specific LSM and we're the first to ask
- * for registration permission,
+ * -or the passed LSM is configured as the default and the user did not
+ * choose an alternate LSM at boot time,
+ * -or there is no default LSM set and the user didn't specify a
+ * specific LSM and we're the first to ask for registration permission,
* -or the passed LSM is currently loaded.
* Otherwise, return false.
*/