diff --git a/sys/security/mac_biba/mac_biba.c b/sys/security/mac_biba/mac_biba.c
index 946ec9004039..6735c2593fd7 100644
--- a/sys/security/mac_biba/mac_biba.c
+++ b/sys/security/mac_biba/mac_biba.c
@@ -60,6 +60,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/pipe.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/msg.h>
 #include <sys/sem.h>
diff --git a/sys/security/mac_lomac/mac_lomac.c b/sys/security/mac_lomac/mac_lomac.c
index 6808257dcc15..bcffa92135ce 100644
--- a/sys/security/mac_lomac/mac_lomac.c
+++ b/sys/security/mac_lomac/mac_lomac.c
@@ -59,6 +59,7 @@
 #include <sys/file.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
+#include <sys/sx.h>
 #include <sys/pipe.h>
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
diff --git a/sys/security/mac_mls/mac_mls.c b/sys/security/mac_mls/mac_mls.c
index ffd97f82486b..76e2cdaa485f 100644
--- a/sys/security/mac_mls/mac_mls.c
+++ b/sys/security/mac_mls/mac_mls.c
@@ -60,6 +60,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/pipe.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/msg.h>
 #include <sys/sem.h>
diff --git a/sys/security/mac_none/mac_none.c b/sys/security/mac_none/mac_none.c
index 11910a6b4f8d..d36d4296f223 100644
--- a/sys/security/mac_none/mac_none.c
+++ b/sys/security/mac_none/mac_none.c
@@ -59,6 +59,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/pipe.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 
 #include <fs/devfs/devfs.h>
diff --git a/sys/security/mac_partition/mac_partition.c b/sys/security/mac_partition/mac_partition.c
index 397e44abb59c..fe3d8e81677d 100644
--- a/sys/security/mac_partition/mac_partition.c
+++ b/sys/security/mac_partition/mac_partition.c
@@ -54,6 +54,7 @@
 #include <sys/file.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 
 #include <fs/devfs/devfs.h>
diff --git a/sys/security/mac_stub/mac_stub.c b/sys/security/mac_stub/mac_stub.c
index 3be11ba9acf7..36b10ea6cf62 100644
--- a/sys/security/mac_stub/mac_stub.c
+++ b/sys/security/mac_stub/mac_stub.c
@@ -62,6 +62,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/pipe.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/msg.h>
 #include <sys/sem.h>
diff --git a/sys/security/mac_test/mac_test.c b/sys/security/mac_test/mac_test.c
index a7441864debb..921e641f7e91 100644
--- a/sys/security/mac_test/mac_test.c
+++ b/sys/security/mac_test/mac_test.c
@@ -57,6 +57,7 @@
 #include <sys/file.h>
 #include <sys/socket.h>
 #include <sys/socketvar.h>
+#include <sys/sx.h>
 #include <sys/sysctl.h>
 #include <sys/msg.h>
 #include <sys/sem.h>