diff --git a/shadowsocks-libev/files/shadowsocks-libev.init b/shadowsocks-libev/files/shadowsocks-libev.init
index a40312443..ce099ae82 100644
--- a/shadowsocks-libev/files/shadowsocks-libev.init
+++ b/shadowsocks-libev/files/shadowsocks-libev.init
@@ -242,8 +242,8 @@ ss_rules_call6() {
 			-s "$ss_redir_servers6" \
 			${local_port_tcp:+-l "$local_port_tcp6"} \
 			${local_port_udp:+-L "$local_port_udp6"} \
-			${src_default:+--src-default "$src_default" \
-			${dst_default:+--dst-default "$dst_default" \
+			${src_default:+--src-default "$src_default"} \
+			${dst_default:+--dst-default "$dst_default"} \
 			${dst_ips_bypass_file:+--dst-bypass-file "$dst_ips_bypass_file"} \
 			${dst_ips_forward_file:+--dst-forward-file "$dst_ips_forward_file"} \
 			${dst_ips_bypass6:+--dst-bypass "$dst_ips_bypass6"} \