diff --git a/services/core/java/com/android/server/am/ActivityManagerService.java b/services/core/java/com/android/server/am/ActivityManagerService.java
index b4c18b13947c8..87bad5c049e07 100644
--- a/services/core/java/com/android/server/am/ActivityManagerService.java
+++ b/services/core/java/com/android/server/am/ActivityManagerService.java
@@ -6916,7 +6916,7 @@ public class ActivityManagerService extends IActivityManager.Stub
         }
     }
 
-    private final boolean attachApplicationLocked(IApplicationThread thread,
+    private boolean attachApplicationLocked(@NonNull IApplicationThread thread,
             int pid) {
 
         // Find the application record that is being attached...  either via
@@ -7221,6 +7221,9 @@ public class ActivityManagerService extends IActivityManager.Stub
 
     @Override
     public final void attachApplication(IApplicationThread thread) {
+        if (thread == null) {
+            throw new SecurityException("Invalid application interface");
+        }
         synchronized (this) {
             int callingPid = Binder.getCallingPid();
             final long origId = Binder.clearCallingIdentity();
diff --git a/services/core/java/com/android/server/am/ActivityStack.java b/services/core/java/com/android/server/am/ActivityStack.java
index 199860597f9a1..c1ea022f1c110 100644
--- a/services/core/java/com/android/server/am/ActivityStack.java
+++ b/services/core/java/com/android/server/am/ActivityStack.java
@@ -3961,6 +3961,11 @@ class ActivityStack<T extends StackWindowController> extends ConfigurationContai
 
     final boolean navigateUpToLocked(ActivityRecord srec, Intent destIntent, int resultCode,
             Intent resultData) {
+        if (srec.app == null || srec.app.thread == null) {
+            // Nothing to do if the caller is not attached, because this method should be called
+            // from an alive activity.
+            return false;
+        }
         final TaskRecord task = srec.getTask();
         final ArrayList<ActivityRecord> activities = task.mActivities;
         final int start = activities.indexOf(srec);
@@ -4012,22 +4017,22 @@ class ActivityStack<T extends StackWindowController> extends ConfigurationContai
         }
 
         if (parent != null && foundParentInTask) {
+            final int callingUid = srec.info.applicationInfo.uid;
             final int parentLaunchMode = parent.info.launchMode;
             final int destIntentFlags = destIntent.getFlags();
             if (parentLaunchMode == ActivityInfo.LAUNCH_SINGLE_INSTANCE ||
                     parentLaunchMode == ActivityInfo.LAUNCH_SINGLE_TASK ||
                     parentLaunchMode == ActivityInfo.LAUNCH_SINGLE_TOP ||
                     (destIntentFlags & Intent.FLAG_ACTIVITY_CLEAR_TOP) != 0) {
-                parent.deliverNewIntentLocked(srec.info.applicationInfo.uid, destIntent,
-                        srec.packageName);
+                parent.deliverNewIntentLocked(callingUid, destIntent, srec.packageName);
             } else {
                 try {
                     ActivityInfo aInfo = AppGlobals.getPackageManager().getActivityInfo(
                             destIntent.getComponent(), 0, srec.userId);
                     int res = mService.mActivityStarter.startActivityLocked(srec.app.thread,
                             destIntent, null /*ephemeralIntent*/, null, aInfo, null /*rInfo*/, null,
-                            null, parent.appToken, null, 0, -1, parent.launchedFromUid,
-                            parent.launchedFromPackage, -1, parent.launchedFromUid, 0, null,
+                            null, parent.appToken, null, 0, -1, callingUid,
+                            srec.packageName, -1, callingUid, 0, null,
                             false, true, null, null, "navigateUpTo");
                     foundParentInTask = res == ActivityManager.START_SUCCESS;
                 } catch (RemoteException e) {
diff --git a/services/tests/servicestests/src/com/android/server/am/ActivityStackTests.java b/services/tests/servicestests/src/com/android/server/am/ActivityStackTests.java
index 02fba082ca98d..33174b2bf0749 100644
--- a/services/tests/servicestests/src/com/android/server/am/ActivityStackTests.java
+++ b/services/tests/servicestests/src/com/android/server/am/ActivityStackTests.java
@@ -122,4 +122,17 @@ public class ActivityStackTests extends ActivityTestsBase {
         assertEquals(task.getTopActivity(true /* includeOverlays */), taskOverlay);
         assertNotNull(result.r);
     }
+
+    @Test
+    public void testNavigateUpTo() {
+        final ActivityManagerService service = createActivityManagerService();
+        final TaskRecord task = createTask(service, testActivityComponent, TEST_STACK_ID);
+        final ActivityRecord activityRecord = createActivity(service, testActivityComponent, task);
+        activityRecord.app = new ProcessRecord(null, activityRecord.appInfo,
+                activityRecord.processName, activityRecord.getUid());
+        final ActivityStack testStack = service.mStackSupervisor.getStack(TEST_STACK_ID);
+        // No-op if the source activity record doesn't have attached process (app.thread == null).
+        assertFalse(testStack.navigateUpToLocked(activityRecord, activityRecord.intent,
+                0 /* resultCode */, null /* resultData */));
+    }
 }