Use PerUidCounter in the connectivity static library
This is a no-op refactoring which uses common PerUidCounter
from the static library and delete the private implementation
inside ConnectivityService. This refactoring includes:
1. Make a private implementation that inherite PerUidCounter
to convert and rethrow exception to maintain backward
compatibility.
2. Adjust per-uid max limit argument in the counter constructor
since the private implementation is already buggy.
3. Use the getter in PerUidCounter for the existing tests.
Test: testNetworkCallbackMaximum
testProfileNetworkPrefCountsRequestsCorrectlyOnSet
testRequestCountLimits
Bug: 235771502
Change-Id: I5c49edab18774acf819828201041c9931fabccc4
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index 7342efa..617894f 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -257,6 +257,7 @@
import com.android.net.module.util.LinkPropertiesUtils.CompareResult;
import com.android.net.module.util.LocationPermissionChecker;
import com.android.net.module.util.NetworkCapabilitiesUtils;
+import com.android.net.module.util.PerUidCounter;
import com.android.net.module.util.PermissionUtils;
import com.android.net.module.util.TcUtils;
import com.android.net.module.util.netlink.InetDiagMessage;
@@ -386,9 +387,9 @@
protected final PermissionMonitor mPermissionMonitor;
@VisibleForTesting
- final PerUidCounter mNetworkRequestCounter;
+ final RequestInfoPerUidCounter mNetworkRequestCounter;
@VisibleForTesting
- final PerUidCounter mSystemNetworkRequestCounter;
+ final RequestInfoPerUidCounter mSystemNetworkRequestCounter;
private volatile boolean mLockdownEnabled;
@@ -1186,71 +1187,6 @@
}
/**
- * 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;
-
- // Map from UID to number of NetworkRequests that UID has filed.
- @VisibleForTesting
- @GuardedBy("mUidToNetworkRequestCount")
- final SparseIntArray mUidToNetworkRequestCount = new SparseIntArray();
-
- /**
- * Constructor
- *
- * @param maxCountPerUid the maximum count per uid allowed
- */
- public PerUidCounter(final int maxCountPerUid) {
- mMaxCountPerUid = maxCountPerUid;
- }
-
- /**
- * Increments the request count of the given uid. Throws an exception if the number
- * of open requests for the uid exceeds the value of maxCounterPerUid which is the value
- * passed into the constructor. see: {@link #PerUidCounter(int)}.
- *
- * @throws ServiceSpecificException with
- * {@link ConnectivityManager.Errors.TOO_MANY_REQUESTS} if the number of requests for
- * the uid exceed the allowed number.
- *
- * @param uid the uid that the request was made under
- */
- public void incrementCountOrThrow(final int uid) {
- synchronized (mUidToNetworkRequestCount) {
- final int newRequestCount = mUidToNetworkRequestCount.get(uid, 0) + 1;
- if (newRequestCount >= mMaxCountPerUid) {
- throw new ServiceSpecificException(
- ConnectivityManager.Errors.TOO_MANY_REQUESTS,
- "Uid " + uid + " exceeded its allotted requests limit");
- }
- mUidToNetworkRequestCount.put(uid, newRequestCount);
- }
- }
-
- /**
- * Decrements the request count of the given uid.
- *
- * @param uid the uid that the request was made under
- */
- public void decrementCount(final int uid) {
- synchronized (mUidToNetworkRequestCount) {
- /* numToDecrement */
- final int newRequestCount = mUidToNetworkRequestCount.get(uid, 0) - 1;
- if (newRequestCount < 0) {
- logwtf("BUG: too small request count " + newRequestCount + " for UID " + uid);
- } else if (newRequestCount == 0) {
- mUidToNetworkRequestCount.delete(uid);
- } else {
- mUidToNetworkRequestCount.put(uid, newRequestCount);
- }
- }
- }
-
- }
-
- /**
* Dependencies of ConnectivityService, for injection in tests.
*/
@VisibleForTesting
@@ -1464,8 +1400,13 @@
mNetIdManager = mDeps.makeNetIdManager();
mContext = Objects.requireNonNull(context, "missing Context");
mResources = deps.getResources(mContext);
- mNetworkRequestCounter = new PerUidCounter(MAX_NETWORK_REQUESTS_PER_UID);
- mSystemNetworkRequestCounter = new PerUidCounter(MAX_NETWORK_REQUESTS_PER_SYSTEM_UID);
+ // The legacy PerUidCounter is buggy and throwing exception at count == limit.
+ // Pass limit - 1 to maintain backward compatibility.
+ // TODO: Remove the workaround.
+ mNetworkRequestCounter =
+ new RequestInfoPerUidCounter(MAX_NETWORK_REQUESTS_PER_UID - 1);
+ mSystemNetworkRequestCounter =
+ new RequestInfoPerUidCounter(MAX_NETWORK_REQUESTS_PER_SYSTEM_UID - 1);
mMetricsLog = logger;
mNetworkRanker = new NetworkRanker();
@@ -4763,7 +4704,7 @@
}
}
}
- nri.decrementRequestCount();
+ nri.mPerUidCounter.decrementCount(nri.mUid);
mNetworkRequestInfoLogs.log("RELEASE " + nri);
checkNrisConsistency(nri);
@@ -4866,7 +4807,7 @@
}
}
- private PerUidCounter getRequestCounter(NetworkRequestInfo nri) {
+ private RequestInfoPerUidCounter getRequestCounter(NetworkRequestInfo nri) {
return checkAnyPermissionOf(
nri.mPid, nri.mUid, NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK)
? mSystemNetworkRequestCounter : mNetworkRequestCounter;
@@ -6230,7 +6171,7 @@
final String mCallingAttributionTag;
// Counter keeping track of this NRI.
- final PerUidCounter mPerUidCounter;
+ final RequestInfoPerUidCounter mPerUidCounter;
// Effective UID of this request. This is different from mUid when a privileged process
// files a request on behalf of another UID. This UID is used to determine blocked status,
@@ -6396,10 +6337,6 @@
return Collections.unmodifiableList(tempRequests);
}
- void decrementRequestCount() {
- mPerUidCounter.decrementCount(mUid);
- }
-
void linkDeathRecipient() {
if (null != mBinder) {
try {
@@ -6461,6 +6398,38 @@
}
}
+ // Keep backward compatibility since the ServiceSpecificException is used by
+ // the API surface, see {@link ConnectivityManager#convertServiceException}.
+ public static class RequestInfoPerUidCounter extends PerUidCounter {
+ RequestInfoPerUidCounter(int maxCountPerUid) {
+ super(maxCountPerUid);
+ }
+
+ @Override
+ public synchronized void incrementCountOrThrow(int uid) {
+ try {
+ super.incrementCountOrThrow(uid);
+ } catch (IllegalStateException e) {
+ throw new ServiceSpecificException(
+ ConnectivityManager.Errors.TOO_MANY_REQUESTS,
+ "Uid " + uid + " exceeded its allotted requests limit");
+ }
+ }
+
+ @Override
+ public synchronized void decrementCountOrThrow(int uid) {
+ throw new UnsupportedOperationException("Use decrementCount instead.");
+ }
+
+ public synchronized void decrementCount(int uid) {
+ try {
+ super.decrementCountOrThrow(uid);
+ } catch (IllegalStateException e) {
+ logwtf("Exception when decrement per uid request count: ", e);
+ }
+ }
+ }
+
// This checks that the passed capabilities either do not request a
// specific SSID/SignalStrength, or the calling app has permission to do so.
private void ensureSufficientPermissionsForRequest(NetworkCapabilities nc,
@@ -9949,7 +9918,7 @@
// Decrement the reference count for this NetworkRequestInfo. The reference count is
// incremented when the NetworkRequestInfo is created as part of
// enforceRequestCountLimit().
- nri.decrementRequestCount();
+ nri.mPerUidCounter.decrementCount(nri.mUid);
return;
}
@@ -10015,7 +9984,7 @@
// Decrement the reference count for this NetworkRequestInfo. The reference count is
// incremented when the NetworkRequestInfo is created as part of
// enforceRequestCountLimit().
- nri.decrementRequestCount();
+ nri.mPerUidCounter.decrementCount(nri.mUid);
iCb.unlinkToDeath(cbInfo, 0);
}