Added guard in ioctlSetAddr for nil IP

peer/wginterface/interface.go

@@ -11,6 +11,7 @@ package wginterface
 
 import (
 	"encoding/binary"
+	"errors"
 	"fmt"
 	"net"
 	"slices"
@@ -173,6 +174,10 @@ func nlAttr(attrType uint16, data []byte) []byte {
 // messages, but the AF_INET ioctl interface is simpler.
 
 func ioctlSetAddr(name string, ip net.IP, prefixLen int) error {
+	if ip.To4() == nil {
+		return errors.New("attempted to set nil IP on interface")
+	}
+
 	fd, err := unix.Socket(unix.AF_INET, unix.SOCK_DGRAM, unix.IPPROTO_IP)
 	if err != nil {
 		return err