diff --git a/common/password.c b/common/password.c
index b5b7655..5b754d9 100644
--- a/common/password.c
+++ b/common/password.c
@@ -111,13 +111,12 @@
 }
 EXPORT_SYMBOL(password);
 
-int is_passwd_default_enable(void)
+static int is_passwd_default_enable(void)
 {
 	return strlen(default_passwd) > 0;
 }
-EXPORT_SYMBOL(is_passwd_default_enable);
 
-int is_passwd_env_enable(void)
+static int is_passwd_env_enable(void)
 {
 	int fd;
 
@@ -130,7 +129,6 @@
 
 	return 1;
 }
-EXPORT_SYMBOL(is_passwd_env_enable);
 
 int passwd_env_disable(void)
 {
@@ -227,7 +225,7 @@
 }
 EXPORT_SYMBOL(read_env_passwd);
 
-int write_env_passwd(unsigned char *sum, size_t length)
+static int write_env_passwd(unsigned char *sum, size_t length)
 {
 	int fd;
 	unsigned char c;
@@ -274,7 +272,6 @@
 
 	return ret;
 }
-EXPORT_SYMBOL(write_env_passwd);
 
 static int check_passwd(unsigned char *passwd, size_t length)
 {