Include user identifier in external storage paths.

When building external storage paths, always include user in path
to enable cross-user paths and aid debugging.

Each Zygote process continues to only have access to the appropriate
user-specific emulated storage through bind mounts. A second set of
mounts continue supporting legacy /sdcard-style paths. For example,
a process running as owner has these mount points:

/storage/emulated_legacy
/storage/emulated_legacy/Android/obb
/storage/emulated/0
/storage/emulated/obb

Since Environment is created before Zygote forks, we need to update
its internal paths after each process launches.

Bug: 7131382
Change-Id: I6f8c6971f2a8edfb415c14cb4ed05ff97e587a21

1 files changed, 6 insertions, 1 deletions

diff --git a/services/java/com/android/server/BackupManagerService.java b/services/java/com/android/server/BackupManagerService.java
index 1d40f4f427f9..5e2b42551d95 100644
--- a/services/java/com/android/server/BackupManagerService.java
+++ b/services/java/com/android/server/BackupManagerService.java
@@ -67,6 +67,7 @@ import android.os.ServiceManager;
 import android.os.SystemClock;
 import android.os.UserHandle;
 import android.os.WorkSource;
+import android.os.Environment.UserEnvironment;
 import android.os.storage.IMountService;
 import android.provider.Settings;
 import android.util.EventLog;
@@ -2720,9 +2721,13 @@ class BackupManagerService extends IBackupManager.Stub {
             FullBackup.backupToTar(pkg.packageName, FullBackup.APK_TREE_TOKEN, null,
                     apkDir, appSourceDir, output);
 
+            // TODO: migrate this to SharedStorageBackup, since AID_SYSTEM
+            // doesn't have access to external storage.
+
             // Save associated .obb content if it exists and we did save the apk
             // check for .obb and save those too
-            final File obbDir = Environment.getExternalStorageAppObbDirectory(pkg.packageName);
+            final UserEnvironment userEnv = new UserEnvironment(UserHandle.USER_OWNER);
+            final File obbDir = userEnv.getExternalStorageAppObbDirectory(pkg.packageName);
             if (obbDir != null) {
                 if (MORE_DEBUG) Log.i(TAG, "obb dir: " + obbDir.getAbsolutePath());
                 File[] obbFiles = obbDir.listFiles();