Intercept unlink(), remove(), and rename().
Handles cases where apps try deleting paths returned in "_data"
columns, and where they try renaming across bind mounts.
Bug: 124349250
Test: atest android.appsecurity.cts.ExternalStorageHostTest#testExternalStorageRename
Change-Id: I7f4461bcacada80398eb95d051a0d29456f63499
diff --git a/core/java/android/app/ActivityThread.java b/core/java/android/app/ActivityThread.java
index b18c4de..b654258 100644
--- a/core/java/android/app/ActivityThread.java
+++ b/core/java/android/app/ActivityThread.java
@@ -182,6 +182,7 @@
import java.lang.ref.WeakReference;
import java.lang.reflect.Method;
import java.net.InetAddress;
+import java.nio.file.Files;
import java.text.DateFormat;
import java.util.ArrayList;
import java.util.Arrays;
@@ -6961,6 +6962,23 @@
}
}
+ private void deleteDeprecatedDataPath(String path) throws ErrnoException {
+ final Uri uri = ContentResolver.translateDeprecatedDataPath(path);
+ Log.v(TAG, "Redirecting " + path + " to " + uri);
+
+ final ContentResolver cr = currentActivityThread().getApplication()
+ .getContentResolver();
+ try {
+ if (cr.delete(uri, null, null) == 0) {
+ throw new FileNotFoundException();
+ }
+ } catch (SecurityException e) {
+ throw new ErrnoException(e.getMessage(), OsConstants.EACCES);
+ } catch (FileNotFoundException e) {
+ throw new ErrnoException(e.getMessage(), OsConstants.ENOENT);
+ }
+ }
+
@Override
public boolean access(String path, int mode) throws ErrnoException {
if (path != null && path.startsWith(DEPRECATE_DATA_PREFIX)) {
@@ -6995,6 +7013,42 @@
return super.stat(path);
}
}
+
+ @Override
+ public void unlink(String path) throws ErrnoException {
+ if (path != null && path.startsWith(DEPRECATE_DATA_PREFIX)) {
+ deleteDeprecatedDataPath(path);
+ } else {
+ super.unlink(path);
+ }
+ }
+
+ @Override
+ public void remove(String path) throws ErrnoException {
+ if (path != null && path.startsWith(DEPRECATE_DATA_PREFIX)) {
+ deleteDeprecatedDataPath(path);
+ } else {
+ super.remove(path);
+ }
+ }
+
+ @Override
+ public void rename(String oldPath, String newPath) throws ErrnoException {
+ try {
+ super.rename(oldPath, newPath);
+ } catch (ErrnoException e) {
+ if (e.errno == OsConstants.EXDEV) {
+ Log.v(TAG, "Recovering failed rename " + oldPath + " to " + newPath);
+ try {
+ Files.move(new File(oldPath).toPath(), new File(newPath).toPath());
+ } catch (IOException e2) {
+ throw e;
+ }
+ } else {
+ throw e;
+ }
+ }
+ }
}
public static void main(String[] args) {