NetLabel: honor the audit_enabled flag

The audit_enabled flag is used to signal when syscall auditing is to be
performed.  While NetLabel uses a Netlink interface instead of syscalls, it is
reasonable to consider the NetLabel Netlink interface as a form of syscall so
pay attention to the audit_enabled flag when generating audit messages in
NetLabel.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>

4 files changed, 50 insertions, 39 deletions

diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c
index fe9851fac85d..743b05734a49 100644
--- a/net/netlabel/netlabel_cipso_v4.c
+++ b/net/netlabel/netlabel_cipso_v4.c
@@ -407,12 +407,14 @@ static int netlbl_cipsov4_add(struct sk_buff *skb, struct genl_info *info)
 
         audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_ADD,
                                               &audit_info);
-        audit_log_format(audit_buf,
-                         " cipso_doi=%u cipso_type=%s res=%u",
-                         doi,
-                         type_str,
-                         ret_val == 0 ? 1 : 0);
-        audit_log_end(audit_buf);
+        if (audit_buf != NULL) {
+                audit_log_format(audit_buf,
+                                 " cipso_doi=%u cipso_type=%s res=%u",
+                                 doi,
+                                 type_str,
+                                 ret_val == 0 ? 1 : 0);
+                audit_log_end(audit_buf);
+        }
 
         return ret_val;
 }
@@ -680,11 +682,13 @@ static int netlbl_cipsov4_remove(struct sk_buff *skb, struct genl_info *info)
 
         audit_buf = netlbl_audit_start_common(AUDIT_MAC_CIPSOV4_DEL,
                                               &audit_info);
-        audit_log_format(audit_buf,
-                         " cipso_doi=%u res=%u",
-                         doi,
-                         ret_val == 0 ? 1 : 0);
-        audit_log_end(audit_buf);
+        if (audit_buf != NULL) {
+                audit_log_format(audit_buf,
+                                 " cipso_doi=%u res=%u",
+                                 doi,
+                                 ret_val == 0 ? 1 : 0);
+                audit_log_end(audit_buf);
+        }
 
         return ret_val;
 }
diff --git a/net/netlabel/netlabel_domainhash.c b/net/netlabel/netlabel_domainhash.c
index af4371d3b459..f46a0aeec44f 100644
--- a/net/netlabel/netlabel_domainhash.c
+++ b/net/netlabel/netlabel_domainhash.c
@@ -202,7 +202,6 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
         int ret_val;
         u32 bkt;
         struct audit_buffer *audit_buf;
-        char *audit_domain;
 
         switch (entry->type) {
         case NETLBL_NLTYPE_UNLABELED:
@@ -243,24 +242,24 @@ int netlbl_domhsh_add(struct netlbl_dom_map *entry,
         } else
                 ret_val = -EINVAL;
 
-        if (entry->domain != NULL)
-                audit_domain = entry->domain;
-        else
-                audit_domain = "(default)";
         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info);
-        audit_log_format(audit_buf, " nlbl_domain=%s", audit_domain);
-        switch (entry->type) {
-        case NETLBL_NLTYPE_UNLABELED:
-                audit_log_format(audit_buf, " nlbl_protocol=unlbl");
-                break;
-        case NETLBL_NLTYPE_CIPSOV4:
+        if (audit_buf != NULL) {
                 audit_log_format(audit_buf,
-                                 " nlbl_protocol=cipsov4 cipso_doi=%u",
-                                 entry->type_def.cipsov4->doi);
-                break;
+                                 " nlbl_domain=%s",
+                                 entry->domain ? entry->domain : "(default)");
+                switch (entry->type) {
+                case NETLBL_NLTYPE_UNLABELED:
+                        audit_log_format(audit_buf, " nlbl_protocol=unlbl");
+                        break;
+                case NETLBL_NLTYPE_CIPSOV4:
+                        audit_log_format(audit_buf,
+                                         " nlbl_protocol=cipsov4 cipso_doi=%u",
+                                         entry->type_def.cipsov4->doi);
+                        break;
+                }
+                audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
+                audit_log_end(audit_buf);
         }
-        audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
-        audit_log_end(audit_buf);
 
         rcu_read_unlock();
 
@@ -310,7 +309,6 @@ int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info)
         int ret_val = -ENOENT;
         struct netlbl_dom_map *entry;
         struct audit_buffer *audit_buf;
-        char *audit_domain;
 
         rcu_read_lock();
         if (domain != NULL)
@@ -348,16 +346,14 @@ int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info)
                 spin_unlock(&netlbl_domhsh_def_lock);
         }
 
-        if (entry->domain != NULL)
-                audit_domain = entry->domain;
-        else
-                audit_domain = "(default)";
         audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
-        audit_log_format(audit_buf,
-                         " nlbl_domain=%s res=%u",
-                         audit_domain,
-                         ret_val == 0 ? 1 : 0);
-        audit_log_end(audit_buf);
+        if (audit_buf != NULL) {
+                audit_log_format(audit_buf,
+                                 " nlbl_domain=%s res=%u",
+                                 entry->domain ? entry->domain : "(default)",
+                                 ret_val == 0 ? 1 : 0);
+                audit_log_end(audit_buf);
+        }
 
         if (ret_val == 0)
                 call_rcu(&entry->rcu, netlbl_domhsh_free_entry);
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 07283e1dfad2..5bc37181662e 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -35,6 +35,7 @@
 #include <linux/socket.h>
 #include <linux/string.h>
 #include <linux/skbuff.h>
+#include <linux/audit.h>
 #include <net/sock.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>
@@ -92,8 +93,11 @@ static void netlbl_unlabel_acceptflg_set(u8 value,
 
         audit_buf = netlbl_audit_start_common(AUDIT_MAC_UNLBL_ALLOW,
                                               audit_info);
-        audit_log_format(audit_buf, " unlbl_accept=%u old=%u", value, old_val);
-        audit_log_end(audit_buf);
+        if (audit_buf != NULL) {
+                audit_log_format(audit_buf,
+                                 " unlbl_accept=%u old=%u", value, old_val);
+                audit_log_end(audit_buf);
+        }
 }
 
 /*
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 98a416381e61..42f12bd65964 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -46,6 +46,10 @@
 #include "netlabel_cipso_v4.h"
 #include "netlabel_user.h"
 
+/* do not do any auditing if audit_enabled == 0, see kernel/audit.c for
+ * details */
+extern int audit_enabled;
+
 /*
  * NetLabel NETLINK Setup Functions
  */
@@ -101,6 +105,9 @@ struct audit_buffer *netlbl_audit_start_common(int type,
         char *secctx;
         u32 secctx_len;
 
+        if (audit_enabled == 0)
+                return NULL;
+
         audit_buf = audit_log_start(audit_ctx, GFP_ATOMIC, type);
         if (audit_buf == NULL)
                 return NULL;