Ensure Binder in-calls to UiModeManagerService are guarded.

Fixed a couple of problems where locks were not being taken or
where the calling identity was being clear deep in the call
stack whereas it should be cleared as close to the entry point
possible to ensure code correctness.

Bug: 7328545
Change-Id: I8ff646a772cd7f4025d5604bc35c6372c3d2428e

1 files changed, 146 insertions, 129 deletions

diff --git a/services/java/com/android/server/UiModeManagerService.java b/services/java/com/android/server/UiModeManagerService.java
index e9e3163..2d4eb79 100644
--- a/services/java/com/android/server/UiModeManagerService.java
+++ b/services/java/com/android/server/UiModeManagerService.java
@@ -51,7 +51,7 @@ import com.android.internal.R;
 import com.android.internal.app.DisableCarModeActivity;
 import com.android.server.TwilightService.TwilightState;
 
-class UiModeManagerService extends IUiModeManager.Stub {
+final class UiModeManagerService extends IUiModeManager.Stub {
     private static final String TAG = UiModeManager.class.getSimpleName();
     private static final boolean LOG = false;
 
@@ -186,57 +186,79 @@ class UiModeManagerService extends IUiModeManager.Stub {
         mTwilightService.registerListener(mTwilightListener, mHandler);
     }
 
+    @Override // Binder call
     public void disableCarMode(int flags) {
-        synchronized (mLock) {
-            setCarModeLocked(false);
-            if (mSystemReady) {
-                updateLocked(0, flags);
+        final long ident = Binder.clearCallingIdentity();
+        try {
+            synchronized (mLock) {
+                setCarModeLocked(false);
+                if (mSystemReady) {
+                    updateLocked(0, flags);
+                }
             }
+        } finally {
+            Binder.restoreCallingIdentity(ident);
         }
     }
 
+    @Override // Binder call
     public void enableCarMode(int flags) {
-        synchronized (mLock) {
-            setCarModeLocked(true);
-            if (mSystemReady) {
-                updateLocked(flags, 0);
+        final long ident = Binder.clearCallingIdentity();
+        try {
+            synchronized (mLock) {
+                setCarModeLocked(true);
+                if (mSystemReady) {
+                    updateLocked(flags, 0);
+                }
             }
+        } finally {
+            Binder.restoreCallingIdentity(ident);
         }
     }
 
+    @Override // Binder call
     public int getCurrentModeType() {
-        synchronized (mLock) {
-            return mCurUiMode & Configuration.UI_MODE_TYPE_MASK;
+        final long ident = Binder.clearCallingIdentity();
+        try {
+            synchronized (mLock) {
+                return mCurUiMode & Configuration.UI_MODE_TYPE_MASK;
+            }
+        } finally {
+            Binder.restoreCallingIdentity(ident);
         }
     }
 
-    public void setNightMode(int mode) throws RemoteException {
-        synchronized (mLock) {
-            switch (mode) {
-                case UiModeManager.MODE_NIGHT_NO:
-                case UiModeManager.MODE_NIGHT_YES:
-                case UiModeManager.MODE_NIGHT_AUTO:
-                    break;
-                default:
-                    throw new IllegalArgumentException("Unknown mode: " + mode);
-            }
-            if (!isDoingNightMode()) {
-                return;
-            }
+    @Override // Binder call
+    public void setNightMode(int mode) {
+        switch (mode) {
+            case UiModeManager.MODE_NIGHT_NO:
+            case UiModeManager.MODE_NIGHT_YES:
+            case UiModeManager.MODE_NIGHT_AUTO:
+                break;
+            default:
+                throw new IllegalArgumentException("Unknown mode: " + mode);
+        }
 
-            if (mNightMode != mode) {
-                long ident = Binder.clearCallingIdentity();
-                Settings.Secure.putInt(mContext.getContentResolver(),
-                        Settings.Secure.UI_NIGHT_MODE, mode);
-                Binder.restoreCallingIdentity(ident);
-                mNightMode = mode;
-                updateLocked(0, 0);
+        final long ident = Binder.clearCallingIdentity();
+        try {
+            synchronized (mLock) {
+                if (isDoingNightModeLocked() && mNightMode != mode) {
+                    Settings.Secure.putInt(mContext.getContentResolver(),
+                            Settings.Secure.UI_NIGHT_MODE, mode);
+                    mNightMode = mode;
+                    updateLocked(0, 0);
+                }
             }
+        } finally {
+            Binder.restoreCallingIdentity(ident);
         }
     }
 
-    public int getNightMode() throws RemoteException {
-        return mNightMode;
+    @Override // Binder call
+    public int getNightMode() {
+        synchronized (mLock) {
+            return mNightMode;
+        }
     }
 
     void systemReady() {
@@ -248,17 +270,17 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    boolean isDoingNightMode() {
+    private boolean isDoingNightModeLocked() {
         return mCarModeEnabled || mDockState != Intent.EXTRA_DOCK_STATE_UNDOCKED;
     }
 
-    void setCarModeLocked(boolean enabled) {
+    private void setCarModeLocked(boolean enabled) {
         if (mCarModeEnabled != enabled) {
             mCarModeEnabled = enabled;
         }
     }
 
-    void updateDockState(int newState) {
+    private void updateDockState(int newState) {
         synchronized (mLock) {
             if (newState != mDockState) {
                 mDockState = newState;
@@ -270,7 +292,7 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    final static boolean isDeskDockState(int state) {
+    private static boolean isDeskDockState(int state) {
         switch (state) {
             case Intent.EXTRA_DOCK_STATE_DESK:
             case Intent.EXTRA_DOCK_STATE_LE_DESK:
@@ -281,7 +303,7 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    final void updateConfigurationLocked() {
+    private void updateConfigurationLocked() {
         int uiMode = mTelevision ? Configuration.UI_MODE_TYPE_TELEVISION : mDefaultUiModeType;
         if (mCarModeEnabled) {
             uiMode = Configuration.UI_MODE_TYPE_CAR;
@@ -315,7 +337,7 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    final void sendConfigurationLocked() {
+    private void sendConfigurationLocked() {
         if (mSetUiMode != mConfiguration.uiMode) {
             mSetUiMode = mConfiguration.uiMode;
 
@@ -327,105 +349,99 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    final void updateLocked(int enableFlags, int disableFlags) {
-        long ident = Binder.clearCallingIdentity();
+    private void updateLocked(int enableFlags, int disableFlags) {
+        String action = null;
+        String oldAction = null;
+        if (mLastBroadcastState == Intent.EXTRA_DOCK_STATE_CAR) {
+            adjustStatusBarCarModeLocked();
+            oldAction = UiModeManager.ACTION_EXIT_CAR_MODE;
+        } else if (isDeskDockState(mLastBroadcastState)) {
+            oldAction = UiModeManager.ACTION_EXIT_DESK_MODE;
+        }
 
-        try {
-            String action = null;
-            String oldAction = null;
-            if (mLastBroadcastState == Intent.EXTRA_DOCK_STATE_CAR) {
+        if (mCarModeEnabled) {
+            if (mLastBroadcastState != Intent.EXTRA_DOCK_STATE_CAR) {
                 adjustStatusBarCarModeLocked();
-                oldAction = UiModeManager.ACTION_EXIT_CAR_MODE;
-            } else if (isDeskDockState(mLastBroadcastState)) {
-                oldAction = UiModeManager.ACTION_EXIT_DESK_MODE;
-            }
 
-            if (mCarModeEnabled) {
-                if (mLastBroadcastState != Intent.EXTRA_DOCK_STATE_CAR) {
-                    adjustStatusBarCarModeLocked();
-
-                    if (oldAction != null) {
-                        mContext.sendBroadcastAsUser(new Intent(oldAction), UserHandle.ALL);
-                    }
-                    mLastBroadcastState = Intent.EXTRA_DOCK_STATE_CAR;
-                    action = UiModeManager.ACTION_ENTER_CAR_MODE;
+                if (oldAction != null) {
+                    mContext.sendBroadcastAsUser(new Intent(oldAction), UserHandle.ALL);
                 }
-            } else if (isDeskDockState(mDockState)) {
-                if (!isDeskDockState(mLastBroadcastState)) {
-                    if (oldAction != null) {
-                        mContext.sendBroadcastAsUser(new Intent(oldAction), UserHandle.ALL);
-                    }
-                    mLastBroadcastState = mDockState;
-                    action = UiModeManager.ACTION_ENTER_DESK_MODE;
+                mLastBroadcastState = Intent.EXTRA_DOCK_STATE_CAR;
+                action = UiModeManager.ACTION_ENTER_CAR_MODE;
+            }
+        } else if (isDeskDockState(mDockState)) {
+            if (!isDeskDockState(mLastBroadcastState)) {
+                if (oldAction != null) {
+                    mContext.sendBroadcastAsUser(new Intent(oldAction), UserHandle.ALL);
                 }
-            } else {
-                mLastBroadcastState = Intent.EXTRA_DOCK_STATE_UNDOCKED;
-                action = oldAction;
+                mLastBroadcastState = mDockState;
+                action = UiModeManager.ACTION_ENTER_DESK_MODE;
             }
+        } else {
+            mLastBroadcastState = Intent.EXTRA_DOCK_STATE_UNDOCKED;
+            action = oldAction;
+        }
 
-            if (action != null) {
-                if (LOG) {
-                    Slog.v(TAG, String.format(
-                        "updateLocked: preparing broadcast: action=%s enable=0x%08x disable=0x%08x",
-                        action, enableFlags, disableFlags));
-                }
+        if (action != null) {
+            if (LOG) {
+                Slog.v(TAG, String.format(
+                    "updateLocked: preparing broadcast: action=%s enable=0x%08x disable=0x%08x",
+                    action, enableFlags, disableFlags));
+            }
 
-                // Send the ordered broadcast; the result receiver will receive after all
-                // broadcasts have been sent. If any broadcast receiver changes the result
-                // code from the initial value of RESULT_OK, then the result receiver will
-                // not launch the corresponding dock application. This gives apps a chance
-                // to override the behavior and stay in their app even when the device is
-                // placed into a dock.
-                Intent intent = new Intent(action);
-                intent.putExtra("enableFlags", enableFlags);
-                intent.putExtra("disableFlags", disableFlags);
-                mContext.sendOrderedBroadcastAsUser(intent, UserHandle.CURRENT, null,
-                        mResultReceiver, null, Activity.RESULT_OK, null, null);
-
-                // Attempting to make this transition a little more clean, we are going
-                // to hold off on doing a configuration change until we have finished
-                // the broadcast and started the home activity.
-                mHoldingConfiguration = true;
-                updateConfigurationLocked();
-            } else {
-                String category = null;
-                if (mCarModeEnabled) {
-                    if (ENABLE_LAUNCH_CAR_DOCK_APP
-                            && (enableFlags & UiModeManager.ENABLE_CAR_MODE_GO_CAR_HOME) != 0) {
-                        category = Intent.CATEGORY_CAR_DOCK;
-                    }
-                } else if (isDeskDockState(mDockState)) {
-                    if (ENABLE_LAUNCH_DESK_DOCK_APP
-                            && (enableFlags & UiModeManager.ENABLE_CAR_MODE_GO_CAR_HOME) != 0) {
-                        category = Intent.CATEGORY_DESK_DOCK;
-                    }
-                } else {
-                    if ((disableFlags & UiModeManager.DISABLE_CAR_MODE_GO_HOME) != 0) {
-                        category = Intent.CATEGORY_HOME;
-                    }
+            // Send the ordered broadcast; the result receiver will receive after all
+            // broadcasts have been sent. If any broadcast receiver changes the result
+            // code from the initial value of RESULT_OK, then the result receiver will
+            // not launch the corresponding dock application. This gives apps a chance
+            // to override the behavior and stay in their app even when the device is
+            // placed into a dock.
+            Intent intent = new Intent(action);
+            intent.putExtra("enableFlags", enableFlags);
+            intent.putExtra("disableFlags", disableFlags);
+            mContext.sendOrderedBroadcastAsUser(intent, UserHandle.CURRENT, null,
+                    mResultReceiver, null, Activity.RESULT_OK, null, null);
+
+            // Attempting to make this transition a little more clean, we are going
+            // to hold off on doing a configuration change until we have finished
+            // the broadcast and started the home activity.
+            mHoldingConfiguration = true;
+            updateConfigurationLocked();
+        } else {
+            String category = null;
+            if (mCarModeEnabled) {
+                if (ENABLE_LAUNCH_CAR_DOCK_APP
+                        && (enableFlags & UiModeManager.ENABLE_CAR_MODE_GO_CAR_HOME) != 0) {
+                    category = Intent.CATEGORY_CAR_DOCK;
                 }
-
-                if (LOG) {
-                    Slog.v(TAG, "updateLocked: null action, mDockState="
-                            + mDockState +", category=" + category);
+            } else if (isDeskDockState(mDockState)) {
+                if (ENABLE_LAUNCH_DESK_DOCK_APP
+                        && (enableFlags & UiModeManager.ENABLE_CAR_MODE_GO_CAR_HOME) != 0) {
+                    category = Intent.CATEGORY_DESK_DOCK;
+                }
+            } else {
+                if ((disableFlags & UiModeManager.DISABLE_CAR_MODE_GO_HOME) != 0) {
+                    category = Intent.CATEGORY_HOME;
                 }
+            }
 
-                sendConfigurationAndStartDreamOrDockAppLocked(category);
+            if (LOG) {
+                Slog.v(TAG, "updateLocked: null action, mDockState="
+                        + mDockState +", category=" + category);
             }
 
-            // keep screen on when charging and in car mode
-            boolean keepScreenOn = mCharging &&
-                    ((mCarModeEnabled && mCarModeKeepsScreenOn) ||
-                     (mCurUiMode == Configuration.UI_MODE_TYPE_DESK && mDeskModeKeepsScreenOn));
-            if (keepScreenOn != mWakeLock.isHeld()) {
-                if (keepScreenOn) {
-                    mWakeLock.acquire();
-                } else {
-                    mWakeLock.release();
-                }
+            sendConfigurationAndStartDreamOrDockAppLocked(category);
+        }
+
+        // keep screen on when charging and in car mode
+        boolean keepScreenOn = mCharging &&
+                ((mCarModeEnabled && mCarModeKeepsScreenOn) ||
+                 (mCurUiMode == Configuration.UI_MODE_TYPE_DESK && mDeskModeKeepsScreenOn));
+        if (keepScreenOn != mWakeLock.isHeld()) {
+            if (keepScreenOn) {
+                mWakeLock.acquire();
+            } else {
+                mWakeLock.release();
             }
-        } finally {
-            Binder.restoreCallingIdentity(ident);
         }
     }
 
@@ -500,7 +516,7 @@ class UiModeManagerService extends IUiModeManager.Stub {
 
         // If we did not start a dock app, then start dreaming if supported.
         if (category != null && !dockAppStarted
-                && isScreenSaverEnabled() && isScreenSaverActivatedOnDock()) {
+                && isScreenSaverEnabledLocked() && isScreenSaverActivatedOnDockLocked()) {
             Slog.i(TAG, "Activating dream while docked.");
             try {
                 IDreamManager dreamManagerService = IDreamManager.Stub.asInterface(
@@ -522,13 +538,13 @@ class UiModeManagerService extends IUiModeManager.Stub {
         }
     }
 
-    private boolean isScreenSaverEnabled() {
+    private boolean isScreenSaverEnabledLocked() {
         return Settings.Secure.getIntForUser(mContext.getContentResolver(),
                 Settings.Secure.SCREENSAVER_ENABLED, DEFAULT_SCREENSAVER_ENABLED,
                 UserHandle.USER_CURRENT) != 0;
     }
 
-    private boolean isScreenSaverActivatedOnDock() {
+    private boolean isScreenSaverActivatedOnDockLocked() {
         return Settings.Secure.getIntForUser(mContext.getContentResolver(),
                 Settings.Secure.SCREENSAVER_ACTIVATE_ON_DOCK,
                 DEFAULT_SCREENSAVER_ACTIVATED_ON_DOCK, UserHandle.USER_CURRENT) != 0;
@@ -536,7 +552,8 @@ class UiModeManagerService extends IUiModeManager.Stub {
 
     private void adjustStatusBarCarModeLocked() {
         if (mStatusBarManager == null) {
-            mStatusBarManager = (StatusBarManager) mContext.getSystemService(Context.STATUS_BAR_SERVICE);
+            mStatusBarManager = (StatusBarManager)
+                    mContext.getSystemService(Context.STATUS_BAR_SERVICE);
         }
 
         // Fear not: StatusBarManagerService manages a list of requests to disable
@@ -581,7 +598,7 @@ class UiModeManagerService extends IUiModeManager.Stub {
 
     private void updateTwilight() {
         synchronized (mLock) {
-            if (isDoingNightMode() && mNightMode == UiModeManager.MODE_NIGHT_AUTO) {
+            if (isDoingNightModeLocked() && mNightMode == UiModeManager.MODE_NIGHT_AUTO) {
                 updateComputedNightModeLocked();
                 updateLocked(0, 0);
             }