From 20091903f60c0d3887da18c47f7e69dd2fb39d5b Mon Sep 17 00:00:00 2001
From: Stanislav Zholnin <zholnin@google.com>
Date: Fri, 14 May 2021 21:11:50 +0100
Subject: [PATCH] Make DiscreteRegistry react only to offsetHistory() calls
 made as TestApi call. Initialize DiscreteRegistry first as it doesn't depend
 on HistoricalRegistry.

There was a wrong assumption that HistoricalRegistry.offsetHistory() is used only for
testing, which was not correct, thus calls to offsetHistory() made during normal
operations of HistoricalRegistry could lead to deadlocks and corruption of timestamps
in DiscreteRegistry.

Fix: 188111112
Fix: 187490443
Bug: 187907266

Test: atest DiscreteAppopsTest

Change-Id: I97aadab497ffea5dd91e6d581bdc39e0a5df3718
---
 .../core/java/com/android/server/appop/AppOpsService.java    | 1 +
 .../java/com/android/server/appop/HistoricalRegistry.java    | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/services/core/java/com/android/server/appop/AppOpsService.java b/services/core/java/com/android/server/appop/AppOpsService.java
index 13dc444dc44bd..137bbe04476c5 100644
--- a/services/core/java/com/android/server/appop/AppOpsService.java
+++ b/services/core/java/com/android/server/appop/AppOpsService.java
@@ -6454,6 +6454,7 @@ public class AppOpsService extends IAppOpsService.Stub {
                 "offsetHistory");
         // Must not hold the appops lock
         mHistoricalRegistry.offsetHistory(offsetMillis);
+        mHistoricalRegistry.offsetDiscreteHistory(offsetMillis);
     }
 
     @Override
diff --git a/services/core/java/com/android/server/appop/HistoricalRegistry.java b/services/core/java/com/android/server/appop/HistoricalRegistry.java
index 35e8d34ce1853..0ab6c4a17032c 100644
--- a/services/core/java/com/android/server/appop/HistoricalRegistry.java
+++ b/services/core/java/com/android/server/appop/HistoricalRegistry.java
@@ -212,6 +212,7 @@ final class HistoricalRegistry {
     }
 
     void systemReady(@NonNull ContentResolver resolver) {
+        mDiscreteRegistry.systemReady();
         final Uri uri = Settings.Global.getUriFor(Settings.Global.APPOP_HISTORY_PARAMETERS);
         resolver.registerContentObserver(uri, false, new ContentObserver(
                 FgThread.getHandler()) {
@@ -249,7 +250,6 @@ final class HistoricalRegistry {
                 }
             }
         }
-        mDiscreteRegistry.systemReady();
     }
 
     private boolean isPersistenceInitializedMLocked() {
@@ -594,6 +594,9 @@ final class HistoricalRegistry {
                 mPersistence.persistHistoricalOpsDLocked(history);
             }
         }
+    }
+
+    void offsetDiscreteHistory(long offsetMillis) {
         mDiscreteRegistry.offsetHistory(offsetMillis);
     }