--- zzzz-none-000/linux-4.9.218/net/ipv4/ipconfig.c 2020-04-02 15:20:41.000000000 +0000 +++ seale-7590ax-750/linux-4.9.218/net/ipv4/ipconfig.c 2023-03-29 10:59:08.000000000 +0000 @@ -455,6 +455,8 @@ ic_netmask = htonl(IN_CLASSB_NET); else if (IN_CLASSC(ntohl(ic_myaddr))) ic_netmask = htonl(IN_CLASSC_NET); + else if (IN_CLASSE(ntohl(ic_myaddr))) + ic_netmask = htonl(IN_CLASSE_NET); else { pr_err("IP-Config: Unable to guess netmask for address %pI4\n", &ic_myaddr);