smack: remove /smack/logging if audit is not configured

If CONFIG_AUDIT is not set then
SMACK does not generate audit messages,
however, keeps audit control file, /smack/logging,
while there is no entity to control.
This change removes audit control file /smack/logging
when audit is not configured in the kernel

Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

Author: goongas

security/smack/smack.h

@@ -432,19 +432,19 @@ static inline struct smack_known *smk_of_current(void)
 	return smk_of_task(smack_cred(current_cred()));
 }
 
+void smack_log(char *subject_label, char *object_label,
+		int request,
+		int result, struct smk_audit_info *auditdata);
+
+#ifdef CONFIG_AUDIT
+
 /*
  * logging functions
  */
 #define SMACK_AUDIT_DENIED 0x1
 #define SMACK_AUDIT_ACCEPT 0x2
 extern int log_policy;
 
-void smack_log(char *subject_label, char *object_label,
-		int request,
-		int result, struct smk_audit_info *auditdata);
-
-#ifdef CONFIG_AUDIT
-
 /*
  * some inline functions to set up audit data
  * they do nothing if CONFIG_AUDIT is not set

security/smack/smack_access.c

@@ -45,11 +45,13 @@ LIST_HEAD(smack_known_list);
  */
 static u32 smack_next_secid = 10;
 
+#ifdef CONFIG_AUDIT
 /*
  * what events do we log
  * can be overwritten at run-time by /smack/logging
  */
 int log_policy = SMACK_AUDIT_DENIED;
+#endif /* CONFIG_AUDIT */
 
 /**
  * smk_access_entry - look up matching access rule

security/smack/smackfs.c

@@ -41,7 +41,9 @@ enum smk_inos {
 	SMK_AMBIENT	= 7,	/* internet ambient label */
 	SMK_NET4ADDR	= 8,	/* single label hosts */
 	SMK_ONLYCAP	= 9,	/* the only "capable" label */
+#ifdef CONFIG_AUDIT
 	SMK_LOGGING	= 10,	/* logging */
+#endif /* CONFIG_AUDIT */
 	SMK_LOAD_SELF	= 11,	/* task specific rules */
 	SMK_ACCESSES	= 12,	/* access policy */
 	SMK_MAPPED	= 13,	/* CIPSO level indicating mapped label */
@@ -2133,6 +2135,7 @@ static const struct file_operations smk_unconfined_ops = {
 };
 #endif /* CONFIG_SECURITY_SMACK_BRINGUP */
 
+#ifdef CONFIG_AUDIT
 /**
  * smk_read_logging - read() for /smack/logging
  * @filp: file pointer, not actually used
@@ -2197,6 +2200,7 @@ static const struct file_operations smk_logging_ops = {
 	.write		= smk_write_logging,
 	.llseek		= default_llseek,
 };
+#endif /* CONFIG_AUDIT */
 
 /*
  * Seq_file read operations for /smack/load-self
@@ -2883,8 +2887,10 @@ static int smk_fill_super(struct super_block *sb, struct fs_context *fc)
 			"netlabel", &smk_net4addr_ops, S_IRUGO|S_IWUSR},
 		[SMK_ONLYCAP] = {
 			"onlycap", &smk_onlycap_ops, S_IRUGO|S_IWUSR},
+#ifdef CONFIG_AUDIT
 		[SMK_LOGGING] = {
 			"logging", &smk_logging_ops, S_IRUGO|S_IWUSR},
+#endif /* CONFIG_AUDIT */
 		[SMK_LOAD_SELF] = {
 			"load-self", &smk_load_self_ops, S_IRUGO|S_IWUGO},
 		[SMK_ACCESSES] = {