Smack: Minor initialisation improvement

This change has two goals:
 - delay the setting of 'smack_enabled' until
   it will be really effective
 - ensure that smackfs is valid only if 'smack_enabled'
   is set (it is already the case in smack_netfilter.c)

Signed-off-by: José Bollo <jose.bollo@iot.bzh>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>

security/smack/smack_lsm.c

@@ -4708,8 +4708,6 @@ static __init int smack_init(void)
 	if (!security_module_enable("smack"))
 		return 0;
 
-	smack_enabled = 1;
-
 	smack_inode_cache = KMEM_CACHE(inode_smack, 0);
 	if (!smack_inode_cache)
 		return -ENOMEM;
@@ -4721,6 +4719,8 @@ static __init int smack_init(void)
 		return -ENOMEM;
 	}
 
+	smack_enabled = 1;
+
 	pr_info("Smack:  Initializing.\n");
 #ifdef CONFIG_SECURITY_SMACK_NETFILTER
 	pr_info("Smack:  Netfilter enabled.\n");

security/smack/smackfs.c

@@ -2892,7 +2892,7 @@ static int __init init_smk_fs(void)
 	int err;
 	int rc;
 
-	if (!security_module_enable("smack"))
+	if (smack_enabled == 0)
 		return 0;
 
 	err = smk_init_sysfs();