diff --git a/network_interface.nim b/network_interface.nim
index c383d5f..b213496 100644
--- a/network_interface.nim
+++ b/network_interface.nim
@@ -37,7 +37,7 @@ proc fromIpAddress*(address: IpAddress): NetworkInterface =
         it.ifa_addr.sa_family.cint == AF_INET6) and
        $address == it.ifa_addr.getAddrString():
       result.ipAddress = address
-      result.netMask = parseIpAddress(it.ifa_addr.getAddrString())
+      result.netMask = parseIpAddress(it.ifa_netmask.getAddrString())
       result.name = $it.ifa_name
       result.index = if_nametoindex(result.name).cint
       result.flags = it.ifa_flags