LSM: Fix security_module_enable() error.

We can set default LSM module to DAC (which means "enable no LSM module").
If default LSM module was set to DAC, security_module_enable() must return 0
unless overridden via boot time parameter.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <jmorris@namei.org>

diff --git a/security/security.c b/security/security.c
index c53949f..43b6463 100644 (file)
--- a/security/security.c
+++ b/security/security.c
@@ -89,20 +89,12 @@ __setup("security=", choose_lsm);
  * Return true if:
  *     -The passed LSM is the one chosen by user at boot time,
  *     -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.
+ *      choose an alternate LSM at boot time.
  * Otherwise, return false.
  */
 int __init security_module_enable(struct security_operations *ops)
 {
-       if (!*chosen_lsm)
-               strncpy(chosen_lsm, ops->name, SECURITY_NAME_MAX);
-       else if (strncmp(ops->name, chosen_lsm, SECURITY_NAME_MAX))
-               return 0;
-
-       return 1;
+       return !strcmp(ops->name, chosen_lsm);
 }
 
 /**