Limit data usage request per uid
Currently, there is no limtation for an app to request
data usage callback, which is dangerous if the app fire
hundreds of thousands requests and potientially this might
cause OOM if the apps don't free them.
Test: atest NetworkStatsObserversTest#testRegister_limit
Bug: 229103088
Change-Id: I8299f46fd47a82ec9b25ba2e0d3c95db5512c331
(cherry picked from commit f3c946278c83ab07ec18b5eb258a54865fc0993f)
Merged-In: I8299f46fd47a82ec9b25ba2e0d3c95db5512c331
diff --git a/service-t/src/com/android/server/net/NetworkStatsObservers.java b/service-t/src/com/android/server/net/NetworkStatsObservers.java
index c51a886..df4e7f5 100644
--- a/service-t/src/com/android/server/net/NetworkStatsObservers.java
+++ b/service-t/src/com/android/server/net/NetworkStatsObservers.java
@@ -44,6 +44,7 @@
import android.util.SparseArray;
import com.android.internal.annotations.VisibleForTesting;
+import com.android.net.module.util.PerUidCounter;
import java.util.concurrent.atomic.AtomicInteger;
@@ -63,10 +64,17 @@
private static final int DUMP_USAGE_REQUESTS_COUNT = 200;
+ // The maximum number of request allowed per uid before an exception is thrown.
+ @VisibleForTesting
+ static final int MAX_REQUESTS_PER_UID = 100;
+
// All access to this map must be done from the handler thread.
// indexed by DataUsageRequest#requestId
private final SparseArray<RequestInfo> mDataUsageRequests = new SparseArray<>();
+ // Request counters per uid, this is thread safe.
+ private final PerUidCounter mDataUsageRequestsPerUid = new PerUidCounter(MAX_REQUESTS_PER_UID);
+
// Sequence number of DataUsageRequests
private final AtomicInteger mNextDataUsageRequestId = new AtomicInteger();
@@ -89,8 +97,9 @@
DataUsageRequest request = buildRequest(context, inputRequest, callingUid);
RequestInfo requestInfo = buildRequestInfo(request, callback, callingPid, callingUid,
callingPackage, accessLevel);
-
if (LOG) Log.d(TAG, "Registering observer for " + requestInfo);
+ mDataUsageRequestsPerUid.incrementCountOrThrow(callingUid);
+
getHandler().sendMessage(mHandler.obtainMessage(MSG_REGISTER, requestInfo));
return request;
}
@@ -189,6 +198,7 @@
if (LOG) Log.d(TAG, "Unregistering " + requestInfo);
mDataUsageRequests.remove(request.requestId);
+ mDataUsageRequestsPerUid.decrementCountOrThrow(callingUid);
requestInfo.unlinkDeathRecipient();
requestInfo.callCallback(NetworkStatsManager.CALLBACK_RELEASED);
}
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index 67a64d5..d3a267a 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -1187,6 +1187,7 @@
/**
* Keeps track of the number of requests made under different uids.
*/
+ // TODO: Remove the hack and use com.android.net.module.util.PerUidCounter instead.
public static class PerUidCounter {
private final int mMaxCountPerUid;
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java b/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
index 13a85e8..e8c9637 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsObserversTest.java
@@ -32,6 +32,7 @@
import static com.android.testutils.DevSdkIgnoreRuleKt.SC_V2;
import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyInt;
@@ -64,6 +65,7 @@
import org.mockito.Mockito;
import org.mockito.MockitoAnnotations;
+import java.util.ArrayList;
import java.util.Objects;
/**
@@ -185,6 +187,51 @@
}
@Test
+ public void testRegister_limit() throws Exception {
+ final DataUsageRequest inputRequest = new DataUsageRequest(
+ DataUsageRequest.REQUEST_ID_UNSET, sTemplateWifi, THRESHOLD_BYTES);
+
+ // Register maximum requests for red.
+ final ArrayList<DataUsageRequest> redRequests = new ArrayList<>();
+ for (int i = 0; i < NetworkStatsObservers.MAX_REQUESTS_PER_UID; i++) {
+ final DataUsageRequest returnedRequest =
+ mStatsObservers.register(mContext, inputRequest, mUsageCallback,
+ PID_RED, UID_RED, PACKAGE_RED, NetworkStatsAccess.Level.DEVICE);
+ redRequests.add(returnedRequest);
+ assertTrue(returnedRequest.requestId > 0);
+ }
+
+ // Verify request exceeds the limit throws.
+ assertThrows(IllegalStateException.class, () ->
+ mStatsObservers.register(mContext, inputRequest, mUsageCallback,
+ PID_RED, UID_RED, PACKAGE_RED, NetworkStatsAccess.Level.DEVICE));
+
+ // Verify another uid is not affected.
+ final ArrayList<DataUsageRequest> blueRequests = new ArrayList<>();
+ for (int i = 0; i < NetworkStatsObservers.MAX_REQUESTS_PER_UID; i++) {
+ final DataUsageRequest returnedRequest =
+ mStatsObservers.register(mContext, inputRequest, mUsageCallback,
+ PID_BLUE, UID_BLUE, PACKAGE_BLUE, NetworkStatsAccess.Level.DEVICE);
+ blueRequests.add(returnedRequest);
+ assertTrue(returnedRequest.requestId > 0);
+ }
+
+ // Again, verify request exceeds the limit throws for the 2nd uid.
+ assertThrows(IllegalStateException.class, () ->
+ mStatsObservers.register(mContext, inputRequest, mUsageCallback,
+ PID_RED, UID_RED, PACKAGE_RED, NetworkStatsAccess.Level.DEVICE));
+
+ // Unregister all registered requests. Note that exceptions cannot be tested since
+ // unregister is handled in the handler thread.
+ for (final DataUsageRequest request : redRequests) {
+ mStatsObservers.unregister(request, UID_RED);
+ }
+ for (final DataUsageRequest request : blueRequests) {
+ mStatsObservers.unregister(request, UID_BLUE);
+ }
+ }
+
+ @Test
public void testUnregister_unknownRequest_noop() throws Exception {
DataUsageRequest unknownRequest = new DataUsageRequest(
123456 /* id */, sTemplateWifi, THRESHOLD_BYTES);