From: Samuel Mannehed <samuel@cendio.se>
Date: Thu, 14 Jun 2018 14:52:36 +0000 (+0200)
Subject: Avoid big strings on the stack
X-Git-Tag: v1.1.0~70
X-Git-Url: https://git.proxmox.com/?p=mirror_novnc.git;a=commitdiff_plain;h=db9daa98a5dedc3ebefea3fe7c09a3fb505fa366

Avoid big strings on the stack

Previous code resulted in RangeErrors by potentially creating big
strings.

Fixes issue #1065
---

diff --git a/core/websock.js b/core/websock.js
index 9291d4e..6b03361 100644
--- a/core/websock.js
+++ b/core/websock.js
@@ -101,7 +101,13 @@ Websock.prototype = {
     rQshiftStr: function (len) {
         if (typeof(len) === 'undefined') { len = this.rQlen(); }
         const arr = this.rQshiftBytes(len);
-        return String.fromCharCode.apply(null, arr);
+        let str = "";
+        // Handle large arrays in steps to avoid long strings on the stack
+        for (let i = 0; i < len; i += 4096) {
+            let part = arr.slice(i, i + Math.min(4096, len));
+            str = str.concat(String.fromCharCode.apply(null, part));
+        }
+        return str;
     },
 
     rQshiftBytes: function (len) {