diff --git a/modules/luci-base/root/usr/share/rpcd/ucode/luci b/modules/luci-base/root/usr/share/rpcd/ucode/luci
index ecc56785fd..79bde16a7f 100644
--- a/modules/luci-base/root/usr/share/rpcd/ucode/luci
+++ b/modules/luci-base/root/usr/share/rpcd/ucode/luci
@@ -231,7 +231,7 @@ const methods = {
                        fd = popen('ipset --help 2>/dev/null');

                        if (fd) {
-                               for (let line = fd.read('line'), flag = false; line != ''; line = fd.read('line')) {
+                               for (let line = fd.read('line'), flag = false; length(line); line = fd.read('line')) {
                                        if (line == 'Supported set types:\n') {
                                                flag = true;
                                        }
@@ -263,7 +263,7 @@ const methods = {
                                let is_vlan_attr = false;
                                let result = {};

-                               for (let line = swc.read('line'); line != ''; line = swc.read('line')) {
+                               for (let line = swc.read('line'); length(line); line = swc.read('line')) {
                                        if (match(line, /^\s+--vlan/)) {
                                                is_vlan_attr = true;
                                        }
@@ -318,7 +318,7 @@ const methods = {
                        if (swc) {
                                let ports = [], port;

-                               for (let line = swc.read('line'); line != ''; line = swc.read('line')) {
+                               for (let line = swc.read('line'); length(line); line = swc.read('line')) {
                                        if (match(line, /^VLAN [0-9]+:/) && length(ports))
                                                break;

@@ -399,7 +399,7 @@ const methods = {
                        if (block) {
                                let result = {};

-                               for (let line = block.read('line'); line != ''; line = block.read('line')) {
+                               for (let line = block.read('line'); length(line); line = block.read('line')) {
                                        let dev = match(line, /^\/dev\/([^:]+):/)?.[1];

                                        if (dev) {
@@ -436,7 +436,7 @@ const methods = {
                        if (fd) {
                                let result = [];

-                               for (let line = fd.read('line'); line != ''; line = fd.read('line')) {
+                               for (let line = fd.read('line'); length(line); line = fd.read('line')) {
                                        const m = split(line, ' ');
                                        const device = replace(m[0], /\\([0-9][0-9][0-9])/g, (m, n) => char(int(n, 8)));
                                        const mount  = replace(m[1], /\\([0-9][0-9][0-9])/g, (m, n) => char(int(n, 8)));