StatsManager uses private object for synchronizing

StatsManager used to synchronize on "this", which is dangerous because
an app can get StatsManager and also sychronize on it, which would block
all calls. We now lock on a private final object.

Test: make
Bug: 144315658
Fixes: 144315658
Change-Id: Ia34b1c586b09a48b244cc16dba77fe54e81f62cf

1 files changed, 16 insertions, 15 deletions

diff --git a/core/java/android/app/StatsManager.java b/core/java/android/app/StatsManager.java
index 11d6528ab6af..2ef05105825a 100644
--- a/core/java/android/app/StatsManager.java
+++ b/core/java/android/app/StatsManager.java
@@ -51,12 +51,13 @@ public final class StatsManager {
     private static final String TAG = "StatsManager";
     private static final boolean DEBUG = false;
 
+    private static final Object sLock = new Object();
     private final Context mContext;
 
-    @GuardedBy("this")
+    @GuardedBy("sLock")
     private IStatsManager mService;
 
-    @GuardedBy("this")
+    @GuardedBy("sLock")
     private IStatsCompanionService mStatsCompanion;
 
     /**
@@ -125,7 +126,7 @@ public final class StatsManager {
      */
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public void addConfig(long configKey, byte[] config) throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 // can throw IllegalArgumentException
@@ -162,7 +163,7 @@ public final class StatsManager {
      */
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public void removeConfig(long configKey) throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 service.removeConfiguration(configKey, mContext.getOpPackageName());
@@ -223,7 +224,7 @@ public final class StatsManager {
     public void setBroadcastSubscriber(
             PendingIntent pendingIntent, long configKey, long subscriberId)
             throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 if (pendingIntent != null) {
@@ -277,7 +278,7 @@ public final class StatsManager {
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public void setFetchReportsOperation(PendingIntent pendingIntent, long configKey)
             throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 if (pendingIntent == null) {
@@ -315,7 +316,7 @@ public final class StatsManager {
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public @NonNull long[] setActiveConfigsChangedOperation(@Nullable PendingIntent pendingIntent)
             throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 if (pendingIntent == null) {
@@ -363,7 +364,7 @@ public final class StatsManager {
      */
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public byte[] getReports(long configKey) throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 return service.getData(configKey, mContext.getOpPackageName());
@@ -400,7 +401,7 @@ public final class StatsManager {
      */
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public byte[] getStatsMetadata() throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 return service.getMetadata(mContext.getOpPackageName());
@@ -435,7 +436,7 @@ public final class StatsManager {
     @RequiresPermission(allOf = {DUMP, PACKAGE_USAGE_STATS})
     public long[] getRegisteredExperimentIds()
             throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 if (service == null) {
@@ -472,7 +473,7 @@ public final class StatsManager {
     @RequiresPermission(allOf = { DUMP, PACKAGE_USAGE_STATS })
     public void setPullerCallback(int atomTag, IStatsPullerCallback callback)
             throws StatsUnavailableException {
-        synchronized (this) {
+        synchronized (sLock) {
             try {
                 IStatsManager service = getIStatsManagerLocked();
                 if (callback == null) {
@@ -515,7 +516,7 @@ public final class StatsManager {
         if (additiveFields == null) {
             additiveFields = new int[0];
         }
-        synchronized (this) {
+        synchronized (sLock) {
             IStatsCompanionService service = getIStatsCompanionServiceLocked();
             PullAtomCallbackInternal rec =
                     new PullAtomCallbackInternal(atomTag, callback, executor);
@@ -649,13 +650,13 @@ public final class StatsManager {
     private class StatsdDeathRecipient implements IBinder.DeathRecipient {
         @Override
         public void binderDied() {
-            synchronized (this) {
+            synchronized (sLock) {
                 mService = null;
             }
         }
     }
 
-    @GuardedBy("this")
+    @GuardedBy("sLock")
     private IStatsManager getIStatsManagerLocked() throws StatsUnavailableException {
         if (mService != null) {
             return mService;
@@ -672,7 +673,7 @@ public final class StatsManager {
         return mService;
     }
 
-    @GuardedBy("this")
+    @GuardedBy("sLock")
     private IStatsCompanionService getIStatsCompanionServiceLocked() {
         if (mStatsCompanion != null) {
             return mStatsCompanion;