Don't crash good-citizen restore session clients

If an app is trying to do the right thing and end its restore sessions
cleanly, but winds up being slow and having the session timed out from
under them, don't crash them with an illegal state exception for having
appeared to end the session twice.

Bug 17133115

Change-Id: I0a0989e2067b156569bddb6626ce045e625c6604

1 files changed, 31 insertions, 0 deletions

diff --git a/services/backup/java/com/android/server/backup/BackupManagerService.java b/services/backup/java/com/android/server/backup/BackupManagerService.java
index 5900612..2e5d43f 100644
--- a/services/backup/java/com/android/server/backup/BackupManagerService.java
+++ b/services/backup/java/com/android/server/backup/BackupManagerService.java
@@ -867,6 +867,7 @@ public class BackupManagerService extends IBackupManager.Stub {
                         // the timeout is suspended while a restore is in progress.  Clean
                         // up now.
                         Slog.w(TAG, "Restore session timed out; aborting");
+                        mActiveRestoreSession.markTimedOut();
                         post(mActiveRestoreSession.new EndRestoreRunnable(
                                 BackupManagerService.this, mActiveRestoreSession));
                     }
@@ -8738,12 +8739,17 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
         private IBackupTransport mRestoreTransport = null;
         RestoreSet[] mRestoreSets = null;
         boolean mEnded = false;
+        boolean mTimedOut = false;
 
         ActiveRestoreSession(String packageName, String transport) {
             mPackageName = packageName;
             mRestoreTransport = getTransport(transport);
         }
 
+        public void markTimedOut() {
+            mTimedOut = true;
+        }
+
         // --- Binder interface ---
         public synchronized int getAvailableRestoreSets(IRestoreObserver observer) {
             mContext.enforceCallingOrSelfPermission(android.Manifest.permission.BACKUP,
@@ -8756,6 +8762,11 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
                 throw new IllegalStateException("Restore session already ended");
             }
 
+            if (mTimedOut) {
+                Slog.i(TAG, "Session already timed out");
+                return -1;
+            }
+
             long oldId = Binder.clearCallingIdentity();
             try {
                 if (mRestoreTransport == null) {
@@ -8787,6 +8798,11 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
                 throw new IllegalStateException("Restore session already ended");
             }
 
+            if (mTimedOut) {
+                Slog.i(TAG, "Session already timed out");
+                return -1;
+            }
+
             if (mRestoreTransport == null || mRestoreSets == null) {
                 Slog.e(TAG, "Ignoring restoreAll() with no restore set");
                 return -1;
@@ -8861,6 +8877,11 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
                 throw new IllegalStateException("Restore session already ended");
             }
 
+            if (mTimedOut) {
+                Slog.i(TAG, "Session already timed out");
+                return -1;
+            }
+
             if (mRestoreTransport == null || mRestoreSets == null) {
                 Slog.e(TAG, "Ignoring restoreAll() with no restore set");
                 return -1;
@@ -8909,6 +8930,11 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
                 throw new IllegalStateException("Restore session already ended");
             }
 
+            if (mTimedOut) {
+                Slog.i(TAG, "Session already timed out");
+                return -1;
+            }
+
             if (mPackageName != null) {
                 if (! mPackageName.equals(packageName)) {
                     Slog.e(TAG, "Ignoring attempt to restore pkg=" + packageName
@@ -9006,6 +9032,11 @@ if (MORE_DEBUG) Slog.v(TAG, "   + got " + nRead + "; now wanting " + (size - soF
         public synchronized void endRestoreSession() {
             if (DEBUG) Slog.d(TAG, "endRestoreSession");
 
+            if (mTimedOut) {
+                Slog.i(TAG, "Session already timed out");
+                return;
+            }
+
             if (mEnded) {
                 throw new IllegalStateException("Restore session already ended");
             }