compiler: Don't read abnormally large arrays (#112)

extremeheat · web-flow · commit 6a625d6b8e72 · 2021-01-01T21:11:18.000+01:00
Avoid OOM crashes when parsing arrays with abnormally large sizes
diff --git a/src/datatypes/compiler-structures.js b/src/datatypes/compiler-structures.js
@@ -10,6 +10,7 @@ module.exports = {
       } else {
         throw new Error('Array must contain either count or countType')
       }
+      code += 'if (count > 0xffffff) throw new Error("array size is abnormally large, not reading: " + count)\n'
       code += 'const data = []\n'
       code += 'let size = countSize\n'
       code += 'for (let i = 0; i < count; i++) {\n'

Original file line number	Diff line number	Diff line change
`@@ -10,6 +10,7 @@ module.exports = {`
`10`	`10`	`} else {`
`11`	`11`	`throw new Error('Array must contain either count or countType')`
`12`	`12`	`}`
	`13`	`+ code += 'if (count > 0xffffff) throw new Error("array size is abnormally large, not reading: " + count)\n'`
`13`	`14`	`code += 'const data = []\n'`
`14`	`15`	`code += 'let size = countSize\n'`
`15`	`16`	`code += 'for (let i = 0; i < count; i++) {\n'`