commit b049513d366c37ca481317c0ff51e49932cae8b3
author Chenbo Feng <fengc@google.com> Wed Apr 10 12:54:41 2019 -0700
committer Chenbo Feng <fengc@google.com> Fri Apr 12 12:16:54 2019 -0700
tree 72a5330af16ab57cc4377aa508c5c3812eeefc82
parent 873ae1491d9ea8a6084ffe6816658cc4c27e22b1

Add overflow protection for network stats maps

Since we moved both uid stats and uid tag stats to the same map now. It
is possible for apps to create as many tags as possible to overflow the
uid tag stats map. To prevent that, add a check when tagging a socket,
and start to block request when a uid created to many entries in the
stats map.

Bug: 111441138
Test: android.app.usage.cts.NetworkUsageStatsTest
      android.net.cts.TrafficStatsTest

Change-Id: I11f42ffc83efc917ac0871a0326375031ae0a6e0

server/TrafficControllerTest.cpp

diff --git a/server/TrafficControllerTest.cpp b/server/TrafficControllerTest.cpp
index 07e3c3e..258d53d 100644
--- a/server/TrafficControllerTest.cpp
+++ b/server/TrafficControllerTest.cpp
@@ -110,6 +110,8 @@
         mTc.mStatsMapA.reset(mFakeUidStatsMap.getMap());
         mTc.mStatsMapB.reset(mFakeTagStatsMap.getMap());
         mTc.mConfigurationMap.reset(mFakeConfigurationMap.getMap());
+        ASSERT_TRUE(isOk(mFakeConfigurationMap.writeValue(CURRENT_STATS_MAP_CONFIGURATION_KEY,
+                                                          SELECT_MAP_A, BPF_ANY)));
         mTc.mUidOwnerMap.reset(mFakeUidOwnerMap.getMap());
         mTc.mUidPermissionMap.reset(mFakeUidPermissionMap.getMap());
         mTc.mPrivilegedUser.clear();