diff --git a/cpp/devices/tap_driver.cpp b/cpp/devices/tap_driver.cpp
index 8f29634a..fa315f84 100644
--- a/cpp/devices/tap_driver.cpp
+++ b/cpp/devices/tap_driver.cpp
@@ -197,7 +197,7 @@ string TapDriver::CreateBridge(int bridge_fd, int ip_fd)
 
 string TapDriver::SetAddressAndNetMask(int fd, const string &interface) const
 {
-    const auto [address, netmask] = ExtractAddressAndMask(inet);
+    const auto [address, netmask] = ExtractAddressAndMask();
     if (address.empty() || netmask.empty()) {
         return "Error extracting inet address and netmask";
     }
@@ -227,11 +227,11 @@ string TapDriver::SetAddressAndNetMask(int fd, const string &interface) const
     return "";
 }
 
-pair<string, string> TapDriver::ExtractAddressAndMask(const string &addr)
+pair<string, string> TapDriver::ExtractAddressAndMask() const
 {
-    string address = addr;
+    string address = inet;
     string netmask = DEFAULT_NETMASK;
-    if (const auto &components = Split(addr, '/', 2); components.size() == 2) {
+    if (const auto &components = Split(inet, '/', 2); components.size() == 2) {
         address = components[0];
 
         int m;
diff --git a/cpp/devices/tap_driver.h b/cpp/devices/tap_driver.h
index 5b4028e1..16cacfc7 100644
--- a/cpp/devices/tap_driver.h
+++ b/cpp/devices/tap_driver.h
@@ -60,7 +60,7 @@ class TapDriver
     static string IpLink(int, const string&, bool);
     static string BrSetIf(int fd, const string&, const string&, bool);
     string CreateBridge(int, int);
-    static pair<string, string> ExtractAddressAndMask(const string&);
+    pair<string, string> ExtractAddressAndMask() const;
     string SetAddressAndNetMask(int, const string&) const;
     string EnablePromiscuousMode() const;