android: Set DexFile to read-only in Java.registerClass() (#318)

As of Android 14, apps with targetSdk >= 34 are not allowed to have writable permissions on dynamically loaded Dex files. https://developer.android.com/about/versions/14/behavior-changes-14#safer-dynamic-code-loading This removes writable permissions from the temporary DexFile created by Java.registerClass() after writing to it and before it gets loaded. Co-authored-by: Georgi Boiko <[email protected]>
frida · May 21, 2024 · 37c1ec5 · 37c1ec5
1 parent 8d7b714
commit 37c1ec5
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/lib/class-factory.js b/lib/class-factory.js
@@ -2193,6 +2193,7 @@ class DexFile {
     const file = new File(filePath, 'w');
     file.write(buffer.buffer);
     file.close();
+    setReadOnlyDex(filePath, factory);
 
     return new DexFile(filePath, fileValue, factory);
   }
@@ -2251,6 +2252,12 @@ function createTemporaryDex (factory) {
   return JFile.createTempFile(tempFileNaming.prefix, tempFileNaming.suffix + '.dex', cacheDirValue);
 }
 
+function setReadOnlyDex (filePath, factory) {
+  const JFile = factory.use('java.io.File');
+  const file = JFile.$new(filePath);
+  file.setWritable(false, false);
+}
+
 function getFactoryCache () {
   switch (factoryCache.state) {
     case 'empty': {