diff --git a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
index a280046..4d1e7ef 100644
--- a/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
+++ b/Tethering/apishim/31/com/android/networkstack/tethering/apishim/api31/BpfCoordinatorShimImpl.java
@@ -167,7 +167,6 @@
 
     @Override
     public boolean addIpv6UpstreamRule(@NonNull final Ipv6UpstreamRule rule) {
-        if (!isInitialized()) return false;
         // RFC7421_PREFIX_LENGTH = 64 which is the most commonly used IPv6 subnet prefix length.
         if (rule.sourcePrefix.getPrefixLength() != RFC7421_PREFIX_LENGTH) return false;
 
@@ -185,7 +184,6 @@
 
     @Override
     public boolean removeIpv6UpstreamRule(@NonNull final Ipv6UpstreamRule rule) {
-        if (!isInitialized()) return false;
         // RFC7421_PREFIX_LENGTH = 64 which is the most commonly used IPv6 subnet prefix length.
         if (rule.sourcePrefix.getPrefixLength() != RFC7421_PREFIX_LENGTH) return false;
 
@@ -200,8 +198,6 @@
 
     @Override
     public boolean addIpv6DownstreamRule(@NonNull final Ipv6DownstreamRule rule) {
-        if (!isInitialized()) return false;
-
         final TetherDownstream6Key key = rule.makeTetherDownstream6Key();
         final Tether6Value value = rule.makeTether6Value();
 
@@ -217,8 +213,6 @@
 
     @Override
     public boolean removeIpv6DownstreamRule(@NonNull final Ipv6DownstreamRule rule) {
-        if (!isInitialized()) return false;
-
         try {
             mBpfDownstream6Map.deleteEntry(rule.makeTetherDownstream6Key());
         } catch (ErrnoException e) {
@@ -234,8 +228,6 @@
     @Override
     @Nullable
     public SparseArray<TetherStatsValue> tetherOffloadGetStats() {
-        if (!isInitialized()) return null;
-
         final SparseArray<TetherStatsValue> tetherStatsList = new SparseArray<TetherStatsValue>();
         try {
             // The reported tether stats are total data usage for all currently-active upstream
@@ -250,8 +242,6 @@
 
     @Override
     public boolean tetherOffloadSetInterfaceQuota(int ifIndex, long quotaBytes) {
-        if (!isInitialized()) return false;
-
         // The common case is an update, where the stats already exist,
         // hence we read first, even though writing with BPF_NOEXIST
         // first would make the code simpler.
@@ -307,8 +297,6 @@
     @Override
     @Nullable
     public TetherStatsValue tetherOffloadGetAndClearStats(int ifIndex) {
-        if (!isInitialized()) return null;
-
         // getAndClearTetherOffloadStats is called after all offload rules have already been
         // deleted for the given upstream interface. Before starting to do cleanup stuff in this
         // function, use synchronizeKernelRCU to make sure that all the current running eBPF
@@ -354,8 +342,6 @@
     @Override
     public boolean tetherOffloadRuleAdd(boolean downstream, @NonNull Tether4Key key,
             @NonNull Tether4Value value) {
-        if (!isInitialized()) return false;
-
         try {
             if (downstream) {
                 mBpfDownstream4Map.insertEntry(key, value);
@@ -379,8 +365,6 @@
 
     @Override
     public boolean tetherOffloadRuleRemove(boolean downstream, @NonNull Tether4Key key) {
-        if (!isInitialized()) return false;
-
         try {
             if (downstream) {
                 if (!mBpfDownstream4Map.deleteEntry(key)) return false;  // Rule did not exist
@@ -413,8 +397,6 @@
     @Override
     public void tetherOffloadRuleForEach(boolean downstream,
             @NonNull ThrowingBiConsumer<Tether4Key, Tether4Value> action) {
-        if (!isInitialized()) return;
-
         try {
             if (downstream) {
                 mBpfDownstream4Map.forEach(action);
@@ -428,8 +410,6 @@
 
     @Override
     public boolean attachProgram(String iface, boolean downstream, boolean ipv4) {
-        if (!isInitialized()) return false;
-
         try {
             BpfUtils.attachProgram(iface, downstream, ipv4);
         } catch (IOException e) {
@@ -441,8 +421,6 @@
 
     @Override
     public boolean detachProgram(String iface, boolean ipv4) {
-        if (!isInitialized()) return false;
-
         try {
             BpfUtils.detachProgram(iface, ipv4);
         } catch (IOException e) {
@@ -460,8 +438,6 @@
 
     @Override
     public boolean addDevMap(int ifIndex) {
-        if (!isInitialized()) return false;
-
         try {
             mBpfDevMap.updateEntry(new TetherDevKey(ifIndex), new TetherDevValue(ifIndex));
         } catch (ErrnoException e) {
@@ -473,8 +449,6 @@
 
     @Override
     public boolean removeDevMap(int ifIndex) {
-        if (!isInitialized()) return false;
-
         try {
             mBpfDevMap.deleteEntry(new TetherDevKey(ifIndex));
         } catch (ErrnoException e) {
diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index a851410..e030902 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -127,6 +127,7 @@
     // TODO: have this configurable
     private static final int DHCP_LEASE_TIME_SECS = 3600;
 
+    private static final int NO_UPSTREAM = 0;
     private static final MacAddress NULL_MAC_ADDRESS = MacAddress.fromString("00:00:00:00:00:00");
 
     private static final String TAG = "IpServer";
@@ -259,6 +260,12 @@
     private int mLastError;
     private int mServingMode;
     private InterfaceSet mUpstreamIfaceSet;  // may change over time
+    // mInterfaceParams can't be final now because IpServer will be created when receives
+    // WIFI_AP_STATE_CHANGED broadcasts or when it detects that the wifi interface has come up.
+    // In the latter case, the interface is not fully initialized and the MAC address might not
+    // be correct (it will be set with a randomized MAC address later).
+    // TODO: Consider create the IpServer only when tethering want to enable it, then we can
+    //       make mInterfaceParams final.
     private InterfaceParams mInterfaceParams;
     // TODO: De-duplicate this with mLinkProperties above. Currently, these link
     // properties are those selected by the IPv6TetheringCoordinator and relayed
@@ -740,7 +747,7 @@
         RaParams params = null;
         String upstreamIface = null;
         InterfaceParams upstreamIfaceParams = null;
-        int upstreamIfIndex = 0;
+        int upstreamIfIndex = NO_UPSTREAM;
 
         if (v6only != null) {
             upstreamIface = v6only.getInterfaceName();
@@ -772,7 +779,7 @@
         // CMD_TETHER_CONNECTION_CHANGED. Adding the mapping update here to the avoid potential
         // timing issue. It prevents that the IPv6 capability is updated later than
         // CMD_TETHER_CONNECTION_CHANGED.
-        mBpfCoordinator.addUpstreamNameToLookupTable(upstreamIfIndex, upstreamIface);
+        mBpfCoordinator.maybeAddUpstreamToLookupTable(upstreamIfIndex, upstreamIface);
 
         // If v6only is null, we pass in null to setRaParams(), which handles
         // deprecation of any existing RA data.
@@ -780,8 +787,7 @@
 
         // Not support BPF on virtual upstream interface
         final boolean upstreamSupportsBpf = upstreamIface != null && !isVcnInterface(upstreamIface);
-        updateIpv6ForwardingRules(
-                mLastIPv6UpstreamIfindex, upstreamIfIndex, upstreamSupportsBpf, null);
+        updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, upstreamIfIndex, upstreamSupportsBpf);
         mLastIPv6LinkProperties = v6only;
         mLastIPv6UpstreamIfindex = upstreamIfIndex;
         mUpstreamSupportsBpf = upstreamSupportsBpf;
@@ -887,25 +893,23 @@
         }
     }
 
-    // Handles all updates to IPv6 forwarding rules. These can currently change only if the upstream
-    // changes or if a neighbor event is received.
+    private int getInterfaceIndexForRule(int ifindex, boolean supportsBpf) {
+        return supportsBpf ? ifindex : NO_UPSTREAM;
+    }
+
+    // Handles updates to IPv6 forwarding rules if the upstream changes.
     private void updateIpv6ForwardingRules(int prevUpstreamIfindex, int upstreamIfindex,
-            boolean upstreamSupportsBpf, NeighborEvent e) {
-        // If no longer have an upstream or upstream not supports BPF, clear forwarding rules and do
-        // nothing else.
-        // TODO: Rather than always clear rules, ensure whether ipv6 ever enable first.
-        if (upstreamIfindex == 0 || !upstreamSupportsBpf) {
-            mBpfCoordinator.tetherOffloadRuleClear(this);
-            return;
-        }
-
+            boolean upstreamSupportsBpf) {
         // If the upstream interface has changed, remove all rules and re-add them with the new
-        // upstream interface.
+        // upstream interface. If upstream is a virtual network, treated as no upstream.
         if (prevUpstreamIfindex != upstreamIfindex) {
-            mBpfCoordinator.tetherOffloadRuleUpdate(this, upstreamIfindex);
+            mBpfCoordinator.updateAllIpv6Rules(this, this.mInterfaceParams,
+                    getInterfaceIndexForRule(upstreamIfindex, upstreamSupportsBpf));
         }
+    }
 
-        // If we're here to process a NeighborEvent, do so now.
+    // Handles updates to IPv6 downstream rules if a neighbor event is received.
+    private void addOrRemoveIpv6Downstream(NeighborEvent e) {
         // mInterfaceParams must be non-null or the event would not have arrived.
         if (e == null) return;
         if (!(e.ip instanceof Inet6Address) || e.ip.isMulticastAddress()
@@ -917,8 +921,9 @@
         // Do this here instead of in the Ipv6DownstreamRule constructor to ensure that we
         // never add rules with a null MAC, only delete them.
         MacAddress dstMac = e.isValid() ? e.macAddr : NULL_MAC_ADDRESS;
-        Ipv6DownstreamRule rule = new Ipv6DownstreamRule(upstreamIfindex, mInterfaceParams.index,
-                (Inet6Address) e.ip, mInterfaceParams.macAddr, dstMac);
+        Ipv6DownstreamRule rule = new Ipv6DownstreamRule(
+                getInterfaceIndexForRule(mLastIPv6UpstreamIfindex, mUpstreamSupportsBpf),
+                mInterfaceParams.index, (Inet6Address) e.ip, mInterfaceParams.macAddr, dstMac);
         if (e.isValid()) {
             mBpfCoordinator.addIpv6DownstreamRule(this, rule);
         } else {
@@ -951,8 +956,7 @@
         if (mInterfaceParams != null
                 && mInterfaceParams.index == e.ifindex
                 && mInterfaceParams.hasMacAddress) {
-            updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, mLastIPv6UpstreamIfindex,
-                    mUpstreamSupportsBpf, e);
+            addOrRemoveIpv6Downstream(e);
             updateClientInfoIpv4(e);
         }
     }
@@ -1285,6 +1289,7 @@
         @Override
         public void exit() {
             cleanupUpstream();
+            mBpfCoordinator.clearAllIpv6Rules(IpServer.this);
             super.exit();
         }
 
@@ -1303,7 +1308,8 @@
 
             for (String ifname : mUpstreamIfaceSet.ifnames) cleanupUpstreamInterface(ifname);
             mUpstreamIfaceSet = null;
-            mBpfCoordinator.tetherOffloadRuleClear(IpServer.this);
+            mBpfCoordinator.updateAllIpv6Rules(
+                    IpServer.this, IpServer.this.mInterfaceParams, NO_UPSTREAM);
         }
 
         private void cleanupUpstreamInterface(String upstreamIface) {
@@ -1370,7 +1376,7 @@
                             final InterfaceParams upstreamIfaceParams =
                                     mDeps.getInterfaceParams(ifname);
                             if (upstreamIfaceParams != null) {
-                                mBpfCoordinator.addUpstreamNameToLookupTable(
+                                mBpfCoordinator.maybeAddUpstreamToLookupTable(
                                         upstreamIfaceParams.index, ifname);
                             }
                         }
@@ -1430,6 +1436,8 @@
     class UnavailableState extends State {
         @Override
         public void enter() {
+            // TODO: move mIpNeighborMonitor.stop() to TetheredState#exit, and trigger a neighbours
+            //       dump after starting mIpNeighborMonitor.
             mIpNeighborMonitor.stop();
             mLastError = TETHER_ERROR_NO_ERROR;
             sendInterfaceState(STATE_UNAVAILABLE);
diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
index 1b23a6c..46c815f 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
@@ -50,6 +50,7 @@
 import android.system.ErrnoException;
 import android.system.OsConstants;
 import android.text.TextUtils;
+import android.util.ArrayMap;
 import android.util.ArraySet;
 import android.util.Log;
 import android.util.SparseArray;
@@ -153,6 +154,7 @@
     static final int NF_CONNTRACK_UDP_TIMEOUT_STREAM = 180;
     @VisibleForTesting
     static final int INVALID_MTU = 0;
+    static final int NO_UPSTREAM = 0;
 
     // List of TCP port numbers which aren't offloaded because the packets require the netfilter
     // conntrack helper. See also TetherController::setForwardRules in netd.
@@ -221,6 +223,23 @@
     // TODO: Remove the unused interface name.
     private final SparseArray<String> mInterfaceNames = new SparseArray<>();
 
+    // How IPv6 upstream rules and downstream rules are managed in BpfCoordinator:
+    // 1. Each upstream rule represents a downstream interface to an upstream interface forwarding.
+    //    No upstream rule will be exist if there is no upstream interface.
+    //    Note that there is at most one upstream interface for a given downstream interface.
+    // 2. Each downstream rule represents an IPv6 neighbor, regardless of the existence of the
+    //    upstream interface. If the upstream is not present, the downstream rules have an upstream
+    //    interface index of NO_UPSTREAM, only exist in BpfCoordinator and won't be written to the
+    //    BPF map. When the upstream comes back, those downstream rules will be updated by calling
+    //    Ipv6DownstreamRule#onNewUpstream and written to the BPF map again. We don't remove the
+    //    downstream rules when upstream is lost is because the upstream may come back with the
+    //    same prefix and we won't receive any neighbor update event in this case.
+    //    TODO: Remove downstream rules when upstream is lost and dump neighbors table when upstream
+    //    interface comes back in order to reconstruct the downstream rules.
+    // 3. It is the same thing for BpfCoordinator if there is no upstream interface or the upstream
+    //    interface is a virtual interface (which currently not supports BPF). In this case,
+    //    IpServer will update its upstream ifindex to NO_UPSTREAM to the BpfCoordinator.
+
     // Map of downstream rule maps. Each of these maps represents the IPv6 forwarding rules for a
     // given downstream. Each map:
     // - Is owned by the IpServer that is responsible for that downstream.
@@ -240,6 +259,16 @@
     private final HashMap<IpServer, LinkedHashMap<Inet6Address, Ipv6DownstreamRule>>
             mIpv6DownstreamRules = new LinkedHashMap<>();
 
+    // Map of IPv6 upstream rules maps. Each of these maps represents the IPv6 upstream rules for a
+    // given downstream. Each map:
+    // - Is owned by the IpServer that is responsible for that downstream.
+    // - Must only be modified by that IpServer.
+    // - Is created when the IpServer adds its first upstream rule, and deleted when the IpServer
+    //   deletes its last upstream rule (or clears its upstream rules)
+    // - Each upstream rule in the ArraySet is corresponding to an upstream interface.
+    private final ArrayMap<IpServer, ArraySet<Ipv6UpstreamRule>>
+            mIpv6UpstreamRules = new ArrayMap<>();
+
     // Map of downstream client maps. Each of these maps represents the IPv4 clients for a given
     // downstream. Needed to build IPv4 forwarding rules when conntrack events are received.
     // Each map:
@@ -603,130 +632,173 @@
     }
 
     /**
-     * Add IPv6 downstream rule. After adding the first rule on a given upstream, must add the data
-     * limit on the given upstream.
-     * Note that this can be only called on handler thread.
+     * Add IPv6 upstream rule. After adding the first rule on a given upstream, must add the
+     * data limit on the given upstream.
      */
-    public void addIpv6DownstreamRule(
-            @NonNull final IpServer ipServer, @NonNull final Ipv6DownstreamRule rule) {
+    private void addIpv6UpstreamRule(
+            @NonNull final IpServer ipServer, @NonNull final Ipv6UpstreamRule rule) {
         if (!isUsingBpf()) return;
 
-        // TODO: Perhaps avoid to add a duplicate rule.
-        if (!mBpfCoordinatorShim.addIpv6DownstreamRule(rule)) return;
-
-        if (!mIpv6DownstreamRules.containsKey(ipServer)) {
-            mIpv6DownstreamRules.put(ipServer, new LinkedHashMap<Inet6Address,
-                    Ipv6DownstreamRule>());
-        }
-        LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules = mIpv6DownstreamRules.get(ipServer);
-
         // Add upstream and downstream interface index to dev map.
         maybeAddDevMap(rule.upstreamIfindex, rule.downstreamIfindex);
 
         // When the first rule is added to an upstream, setup upstream forwarding and data limit.
         maybeSetLimit(rule.upstreamIfindex);
 
-        if (!isAnyRuleFromDownstreamToUpstream(rule.downstreamIfindex, rule.upstreamIfindex)) {
-            // TODO: support upstream forwarding on non-point-to-point interfaces.
-            // TODO: get the MTU from LinkProperties and update the rules when it changes.
-            Ipv6UpstreamRule upstreamRule = new Ipv6UpstreamRule(rule.upstreamIfindex,
-                    rule.downstreamIfindex, IPV6_ZERO_PREFIX64, rule.srcMac, NULL_MAC_ADDRESS,
-                    NULL_MAC_ADDRESS);
-            if (!mBpfCoordinatorShim.addIpv6UpstreamRule(upstreamRule)) {
-                mLog.e("Failed to add upstream IPv6 forwarding rule: " + upstreamRule);
-            }
+        // TODO: support upstream forwarding on non-point-to-point interfaces.
+        // TODO: get the MTU from LinkProperties and update the rules when it changes.
+        if (!mBpfCoordinatorShim.addIpv6UpstreamRule(rule)) {
+            return;
         }
 
-        // Must update the adding rule after calling #isAnyRuleOnUpstream because it needs to
-        // check if it is about adding a first rule for a given upstream.
+        ArraySet<Ipv6UpstreamRule> rules = mIpv6UpstreamRules.computeIfAbsent(
+                ipServer, k -> new ArraySet<Ipv6UpstreamRule>());
+        rules.add(rule);
+    }
+
+    /**
+     * Clear all IPv6 upstream rules for a given downstream. After removing the last rule on a given
+     * upstream, must clear data limit, update the last tether stats and remove the tether stats in
+     * the BPF maps.
+     */
+    private void clearIpv6UpstreamRules(@NonNull final IpServer ipServer) {
+        if (!isUsingBpf()) return;
+
+        final ArraySet<Ipv6UpstreamRule> upstreamRules = mIpv6UpstreamRules.remove(ipServer);
+        if (upstreamRules == null) return;
+
+        int upstreamIfindex = 0;
+        for (Ipv6UpstreamRule rule: upstreamRules) {
+            if (upstreamIfindex != 0 && rule.upstreamIfindex != upstreamIfindex) {
+                Log.wtf(TAG, "BUG: upstream rules point to more than one interface");
+            }
+            upstreamIfindex = rule.upstreamIfindex;
+            mBpfCoordinatorShim.removeIpv6UpstreamRule(rule);
+        }
+        // Clear the limit if there are no more rules on the given upstream.
+        // Using upstreamIfindex outside the loop is fine because all the rules for a given IpServer
+        // will always have the same upstream index (since they are always added all together by
+        // updateAllIpv6Rules).
+        // The upstreamIfindex can't be 0 because we won't add an Ipv6UpstreamRule with
+        // upstreamIfindex == 0 and if there is no Ipv6UpstreamRule for an IpServer, it will be
+        // removed from mIpv6UpstreamRules.
+        if (upstreamIfindex == 0) {
+            Log.wtf(TAG, "BUG: upstream rules have empty Set or rule.upstreamIfindex == 0");
+            return;
+        }
+        maybeClearLimit(upstreamIfindex);
+    }
+
+    /**
+     * Add IPv6 downstream rule.
+     * Note that this can be only called on handler thread.
+     */
+    public void addIpv6DownstreamRule(
+            @NonNull final IpServer ipServer, @NonNull final Ipv6DownstreamRule rule) {
+        if (!isUsingBpf()) return;
+
+        // TODO: Perhaps avoid to add a duplicate rule.
+        if (rule.upstreamIfindex != NO_UPSTREAM
+                && !mBpfCoordinatorShim.addIpv6DownstreamRule(rule)) return;
+
+        LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules =
+                mIpv6DownstreamRules.computeIfAbsent(ipServer,
+                        k -> new LinkedHashMap<Inet6Address, Ipv6DownstreamRule>());
         rules.put(rule.address, rule);
     }
 
     /**
-     * Remove IPv6 downstream rule. After removing the last rule on a given upstream, must clear
-     * data limit, update the last tether stats and remove the tether stats in the BPF maps.
+     * Remove IPv6 downstream rule.
      * Note that this can be only called on handler thread.
      */
     public void removeIpv6DownstreamRule(
             @NonNull final IpServer ipServer, @NonNull final Ipv6DownstreamRule rule) {
         if (!isUsingBpf()) return;
 
-        if (!mBpfCoordinatorShim.removeIpv6DownstreamRule(rule)) return;
+        if (rule.upstreamIfindex != NO_UPSTREAM
+                && !mBpfCoordinatorShim.removeIpv6DownstreamRule(rule)) return;
 
         LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules = mIpv6DownstreamRules.get(ipServer);
         if (rules == null) return;
 
-        // Must remove rules before calling #isAnyRuleOnUpstream because it needs to check if
-        // the last rule is removed for a given upstream. If no rule is removed, return early.
-        // Avoid unnecessary work on a non-existent rule which may have never been added or
-        // removed already.
+        // If no rule is removed, return early. Avoid unnecessary work on a non-existent rule which
+        // may have never been added or removed already.
         if (rules.remove(rule.address) == null) return;
 
         // Remove the downstream entry if it has no more rule.
         if (rules.isEmpty()) {
             mIpv6DownstreamRules.remove(ipServer);
         }
+    }
 
-        // If no more rules between this upstream and downstream, stop upstream forwarding.
-        if (!isAnyRuleFromDownstreamToUpstream(rule.downstreamIfindex, rule.upstreamIfindex)) {
-            Ipv6UpstreamRule upstreamRule = new Ipv6UpstreamRule(rule.upstreamIfindex,
-                    rule.downstreamIfindex, IPV6_ZERO_PREFIX64, rule.srcMac, NULL_MAC_ADDRESS,
-                    NULL_MAC_ADDRESS);
-            if (!mBpfCoordinatorShim.removeIpv6UpstreamRule(upstreamRule)) {
-                mLog.e("Failed to remove upstream IPv6 forwarding rule: " + upstreamRule);
-            }
+    /**
+      * Clear all downstream rules for a given IpServer and return a copy of all removed rules.
+      */
+    @Nullable
+    private Collection<Ipv6DownstreamRule> clearIpv6DownstreamRules(
+            @NonNull final IpServer ipServer) {
+        final LinkedHashMap<Inet6Address, Ipv6DownstreamRule> downstreamRules =
+                mIpv6DownstreamRules.remove(ipServer);
+        if (downstreamRules == null) return null;
+
+        final Collection<Ipv6DownstreamRule> removedRules = downstreamRules.values();
+        for (final Ipv6DownstreamRule rule : removedRules) {
+            if (rule.upstreamIfindex == NO_UPSTREAM) continue;
+            mBpfCoordinatorShim.removeIpv6DownstreamRule(rule);
         }
-
-        // Do cleanup functionality if there is no more rule on the given upstream.
-        maybeClearLimit(rule.upstreamIfindex);
+        return removedRules;
     }
 
     /**
      * Clear all forwarding rules for a given downstream.
      * Note that this can be only called on handler thread.
-     * TODO: rename to tetherOffloadRuleClear6 because of IPv6 only.
      */
-    public void tetherOffloadRuleClear(@NonNull final IpServer ipServer) {
+    public void clearAllIpv6Rules(@NonNull final IpServer ipServer) {
         if (!isUsingBpf()) return;
 
-        final LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules =
-                mIpv6DownstreamRules.get(ipServer);
-        if (rules == null) return;
-
-        // Need to build a rule list because the rule map may be changed in the iteration.
-        for (final Ipv6DownstreamRule rule : new ArrayList<Ipv6DownstreamRule>(rules.values())) {
-            removeIpv6DownstreamRule(ipServer, rule);
-        }
+        // Clear downstream rules first, because clearing upstream rules fetches the stats, and
+        // fetching the stats requires that no rules be forwarding traffic to or from the upstream.
+        clearIpv6DownstreamRules(ipServer);
+        clearIpv6UpstreamRules(ipServer);
     }
 
     /**
-     * Update existing forwarding rules to new upstream for a given downstream.
+     * Delete all upstream and downstream rules for the passed-in IpServer, and if the new upstream
+     * is nonzero, reapply them to the new upstream.
      * Note that this can be only called on handler thread.
      */
-    public void tetherOffloadRuleUpdate(@NonNull final IpServer ipServer, int newUpstreamIfindex) {
+    public void updateAllIpv6Rules(@NonNull final IpServer ipServer,
+            final InterfaceParams interfaceParams, int newUpstreamIfindex) {
         if (!isUsingBpf()) return;
 
-        final LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules =
-                mIpv6DownstreamRules.get(ipServer);
-        if (rules == null) return;
+        // Remove IPv6 downstream rules. Remove the old ones before adding the new rules, otherwise
+        // we need to keep a copy of the old rules.
+        // We still need to keep the downstream rules even when the upstream goes away because it
+        // may come back with the same prefixes (unlikely, but possible). Neighbor entries won't be
+        // deleted and we're not expected to receive new Neighbor events in this case.
+        // TODO: Add new rule first to reduce the latency which has no rule. But this is okay
+        //       because if this is a new upstream, it will probably have different prefixes than
+        //       the one these downstream rules are in. If so, they will never see any downstream
+        //       traffic before new neighbor entries are created.
+        final Collection<Ipv6DownstreamRule> deletedDownstreamRules =
+                clearIpv6DownstreamRules(ipServer);
 
-        // Need to build a rule list because the rule map may be changed in the iteration.
-        // First remove all the old rules, then add all the new rules. This is because the upstream
-        // forwarding code in addIpv6DownstreamRule cannot support rules on two upstreams at the
-        // same time. Deleting the rules first ensures that upstream forwarding is disabled on the
-        // old upstream when the last rule is removed from it, and re-enabled on the new upstream
-        // when the first rule is added to it.
-        // TODO: Once the IPv6 client processing code has moved from IpServer to BpfCoordinator, do
-        // something smarter.
-        final ArrayList<Ipv6DownstreamRule> rulesCopy = new ArrayList<>(rules.values());
-        for (final Ipv6DownstreamRule rule : rulesCopy) {
-            // Remove the old rule before adding the new one because the map uses the same key for
-            // both rules. Reversing the processing order causes that the new rule is removed as
-            // unexpected.
-            // TODO: Add new rule first to reduce the latency which has no rule.
-            removeIpv6DownstreamRule(ipServer, rule);
+        // Remove IPv6 upstream rules. Downstream rules must be removed first because
+        // BpfCoordinatorShimImpl#tetherOffloadGetAndClearStats will be called after the removal of
+        // the last upstream rule and it requires that no rules be forwarding traffic to or from
+        // that upstream.
+        clearIpv6UpstreamRules(ipServer);
+
+        // Add new upstream rules.
+        if (newUpstreamIfindex != 0 && interfaceParams != null && interfaceParams.macAddr != null) {
+            addIpv6UpstreamRule(ipServer, new Ipv6UpstreamRule(
+                    newUpstreamIfindex, interfaceParams.index, IPV6_ZERO_PREFIX64,
+                    interfaceParams.macAddr, NULL_MAC_ADDRESS, NULL_MAC_ADDRESS));
         }
-        for (final Ipv6DownstreamRule rule : rulesCopy) {
+
+        // Add updated downstream rules.
+        if (deletedDownstreamRules == null) return;
+        for (final Ipv6DownstreamRule rule : deletedDownstreamRules) {
             addIpv6DownstreamRule(ipServer, rule.onNewUpstream(newUpstreamIfindex));
         }
     }
@@ -737,7 +809,7 @@
      * expects the interface name in NetworkStats object.
      * Note that this can be only called on handler thread.
      */
-    public void addUpstreamNameToLookupTable(int upstreamIfindex, @NonNull String upstreamIface) {
+    public void maybeAddUpstreamToLookupTable(int upstreamIfindex, @Nullable String upstreamIface) {
         if (!isUsingBpf()) return;
 
         if (upstreamIfindex == 0 || TextUtils.isEmpty(upstreamIface)) return;
@@ -1007,7 +1079,7 @@
      * TODO: consider error handling if the attach program failed.
      */
     public void maybeAttachProgram(@NonNull String intIface, @NonNull String extIface) {
-        if (isVcnInterface(extIface)) return;
+        if (!isUsingBpf() || isVcnInterface(extIface)) return;
 
         if (forwardingPairExists(intIface, extIface)) return;
 
@@ -1031,6 +1103,8 @@
      * Detach BPF program
      */
     public void maybeDetachProgram(@NonNull String intIface, @NonNull String extIface) {
+        if (!isUsingBpf()) return;
+
         forwardingPairRemove(intIface, extIface);
 
         // Detaching program may fail because the interface has been removed already.
@@ -1967,9 +2041,8 @@
     }
 
     private int getInterfaceIndexFromRules(@NonNull String ifName) {
-        for (LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules :
-                mIpv6DownstreamRules.values()) {
-            for (Ipv6DownstreamRule rule : rules.values()) {
+        for (ArraySet<Ipv6UpstreamRule> rules : mIpv6UpstreamRules.values()) {
+            for (Ipv6UpstreamRule rule : rules) {
                 final int upstreamIfindex = rule.upstreamIfindex;
                 if (TextUtils.equals(ifName, mInterfaceNames.get(upstreamIfindex))) {
                     return upstreamIfindex;
@@ -1987,6 +2060,7 @@
     }
 
     private boolean sendDataLimitToBpfMap(int ifIndex, long quotaBytes) {
+        if (!isUsingBpf()) return false;
         if (ifIndex == 0) {
             Log.wtf(TAG, "Invalid interface index.");
             return false;
@@ -2060,28 +2134,14 @@
     // TODO: Rename to isAnyIpv6RuleOnUpstream and define an isAnyRuleOnUpstream method that called
     // both isAnyIpv6RuleOnUpstream and mBpfCoordinatorShim.isAnyIpv4RuleOnUpstream.
     private boolean isAnyRuleOnUpstream(int upstreamIfindex) {
-        for (LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules :
-                mIpv6DownstreamRules.values()) {
-            for (Ipv6DownstreamRule rule : rules.values()) {
+        for (ArraySet<Ipv6UpstreamRule> rules : mIpv6UpstreamRules.values()) {
+            for (Ipv6UpstreamRule rule : rules) {
                 if (upstreamIfindex == rule.upstreamIfindex) return true;
             }
         }
         return false;
     }
 
-    private boolean isAnyRuleFromDownstreamToUpstream(int downstreamIfindex, int upstreamIfindex) {
-        for (LinkedHashMap<Inet6Address, Ipv6DownstreamRule> rules :
-                mIpv6DownstreamRules.values()) {
-            for (Ipv6DownstreamRule rule : rules.values()) {
-                if (downstreamIfindex == rule.downstreamIfindex
-                        && upstreamIfindex == rule.upstreamIfindex) {
-                    return true;
-                }
-            }
-        }
-        return false;
-    }
-
     // TODO: remove the index from map while the interface has been removed because the map size
     // is 64 entries. See packages\modules\Connectivity\Tethering\bpf_progs\offload.c.
     private void maybeAddDevMap(int upstreamIfindex, int downstreamIfindex) {
diff --git a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
index c0718d1..d497a4d 100644
--- a/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
+++ b/Tethering/tests/unit/src/android/net/ip/IpServerTest.java
@@ -158,6 +158,7 @@
     private static final String UPSTREAM_IFACE = "upstream0";
     private static final String UPSTREAM_IFACE2 = "upstream1";
     private static final String IPSEC_IFACE = "ipsec0";
+    private static final int NO_UPSTREAM = 0;
     private static final int UPSTREAM_IFINDEX = 101;
     private static final int UPSTREAM_IFINDEX2 = 102;
     private static final int IPSEC_IFINDEX = 103;
@@ -274,8 +275,18 @@
             LinkProperties lp = new LinkProperties();
             lp.setInterfaceName(upstreamIface);
             dispatchTetherConnectionChanged(upstreamIface, lp, 0);
+            if (usingBpfOffload) {
+                InterfaceParams interfaceParams = mDependencies.getInterfaceParams(upstreamIface);
+                assertNotNull("missing upstream interface: " + upstreamIface, interfaceParams);
+                verify(mBpfCoordinator).updateAllIpv6Rules(
+                        mIpServer, TEST_IFACE_PARAMS, interfaceParams.index);
+                verifyStartUpstreamIpv6Forwarding(null, interfaceParams.index);
+            } else {
+                verifyNoUpstreamIpv6ForwardingChange(null);
+            }
         }
-        reset(mNetd, mCallback, mAddressCoordinator, mBpfCoordinator);
+        reset(mCallback, mAddressCoordinator);
+        resetNetdBpfMapAndCoordinator();
         when(mAddressCoordinator.requestDownstreamAddress(any(), anyInt(),
                 anyBoolean())).thenReturn(mTestAddress);
     }
@@ -531,7 +542,7 @@
         InOrder inOrder = inOrder(mNetd, mBpfCoordinator);
 
         // Add the forwarding pair <IFACE_NAME, UPSTREAM_IFACE>.
-        inOrder.verify(mBpfCoordinator).addUpstreamNameToLookupTable(UPSTREAM_IFINDEX,
+        inOrder.verify(mBpfCoordinator).maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX,
                 UPSTREAM_IFACE);
         inOrder.verify(mBpfCoordinator).maybeAttachProgram(IFACE_NAME, UPSTREAM_IFACE);
         inOrder.verify(mNetd).tetherAddForward(IFACE_NAME, UPSTREAM_IFACE);
@@ -553,7 +564,7 @@
         inOrder.verify(mNetd).tetherRemoveForward(IFACE_NAME, UPSTREAM_IFACE);
 
         // Add the forwarding pair <IFACE_NAME, UPSTREAM_IFACE2>.
-        inOrder.verify(mBpfCoordinator).addUpstreamNameToLookupTable(UPSTREAM_IFINDEX2,
+        inOrder.verify(mBpfCoordinator).maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX2,
                 UPSTREAM_IFACE2);
         inOrder.verify(mBpfCoordinator).maybeAttachProgram(IFACE_NAME, UPSTREAM_IFACE2);
         inOrder.verify(mNetd).tetherAddForward(IFACE_NAME, UPSTREAM_IFACE2);
@@ -578,7 +589,7 @@
 
         // Add the forwarding pair <IFACE_NAME, UPSTREAM_IFACE2> and expect that failed on
         // tetherAddForward.
-        inOrder.verify(mBpfCoordinator).addUpstreamNameToLookupTable(UPSTREAM_IFINDEX2,
+        inOrder.verify(mBpfCoordinator).maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX2,
                 UPSTREAM_IFACE2);
         inOrder.verify(mBpfCoordinator).maybeAttachProgram(IFACE_NAME, UPSTREAM_IFACE2);
         inOrder.verify(mNetd).tetherAddForward(IFACE_NAME, UPSTREAM_IFACE2);
@@ -606,7 +617,7 @@
 
         // Add the forwarding pair <IFACE_NAME, UPSTREAM_IFACE2> and expect that failed on
         // ipfwdAddInterfaceForward.
-        inOrder.verify(mBpfCoordinator).addUpstreamNameToLookupTable(UPSTREAM_IFINDEX2,
+        inOrder.verify(mBpfCoordinator).maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX2,
                 UPSTREAM_IFACE2);
         inOrder.verify(mBpfCoordinator).maybeAttachProgram(IFACE_NAME, UPSTREAM_IFACE2);
         inOrder.verify(mNetd).tetherAddForward(IFACE_NAME, UPSTREAM_IFACE2);
@@ -627,7 +638,15 @@
         inOrder.verify(mBpfCoordinator).maybeDetachProgram(IFACE_NAME, UPSTREAM_IFACE);
         inOrder.verify(mNetd).ipfwdRemoveInterfaceForward(IFACE_NAME, UPSTREAM_IFACE);
         inOrder.verify(mNetd).tetherRemoveForward(IFACE_NAME, UPSTREAM_IFACE);
-        inOrder.verify(mBpfCoordinator).tetherOffloadRuleClear(mIpServer);
+        inOrder.verify(mBpfCoordinator).updateAllIpv6Rules(
+                mIpServer, TEST_IFACE_PARAMS, NO_UPSTREAM);
+        if (!mBpfDeps.isAtLeastS()) {
+            inOrder.verify(mNetd).tetherOffloadGetAndClearStats(UPSTREAM_IFINDEX);
+        }
+        // When tethering stops, upstream interface is set to zero and thus clearing all upstream
+        // rules. Downstream rules are needed to be cleared explicitly by calling
+        // BpfCoordinator#clearAllIpv6Rules in TetheredState#exit.
+        inOrder.verify(mBpfCoordinator).clearAllIpv6Rules(mIpServer);
         inOrder.verify(mNetd).tetherApplyDnsInterfaces();
         inOrder.verify(mNetd).tetherInterfaceRemove(IFACE_NAME);
         inOrder.verify(mNetd).networkRemoveInterface(INetd.LOCAL_NET_ID, IFACE_NAME);
@@ -1064,13 +1083,12 @@
         recvNewNeigh(notMyIfindex, neighA, NUD_REACHABLE, macA);
         verifyNoMoreInteractions(mBpfCoordinator, mNetd, mBpfDownstream6Map, mBpfUpstream6Map);
 
-        // Events on this interface are received and sent to netd.
+        // Events on this interface are received and sent to BpfCoordinator.
         recvNewNeigh(myIfindex, neighA, NUD_REACHABLE, macA);
         verify(mBpfCoordinator).addIpv6DownstreamRule(
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighA, macA));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
-        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
         resetNetdBpfMapAndCoordinator();
 
         recvNewNeigh(myIfindex, neighB, NUD_REACHABLE, macB);
@@ -1078,7 +1096,6 @@
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighB, macB));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
-        verifyNoUpstreamIpv6ForwardingChange(null);
         resetNetdBpfMapAndCoordinator();
 
         // Link-local and multicast neighbors are ignored.
@@ -1094,7 +1111,6 @@
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighA, macNull));
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macNull);
-        verifyNoUpstreamIpv6ForwardingChange(null);
         resetNetdBpfMapAndCoordinator();
 
         // A neighbor that is deleted causes the rule to be removed.
@@ -1103,12 +1119,10 @@
                 mIpServer,  makeDownstreamRule(UPSTREAM_IFINDEX, neighB, macNull));
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macNull);
-        verifyStopUpstreamIpv6Forwarding(null);
         resetNetdBpfMapAndCoordinator();
 
         // Upstream changes result in updating the rules.
         recvNewNeigh(myIfindex, neighA, NUD_REACHABLE, macA);
-        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
         recvNewNeigh(myIfindex, neighB, NUD_REACHABLE, macB);
         resetNetdBpfMapAndCoordinator();
 
@@ -1116,89 +1130,100 @@
         LinkProperties lp = new LinkProperties();
         lp.setInterfaceName(UPSTREAM_IFACE2);
         dispatchTetherConnectionChanged(UPSTREAM_IFACE2, lp, -1);
-        verify(mBpfCoordinator).tetherOffloadRuleUpdate(mIpServer, UPSTREAM_IFINDEX2);
+        verify(mBpfCoordinator).updateAllIpv6Rules(mIpServer, TEST_IFACE_PARAMS, UPSTREAM_IFINDEX2);
         verifyTetherOffloadRuleRemove(inOrder,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
         verifyTetherOffloadRuleRemove(inOrder,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
         verifyStopUpstreamIpv6Forwarding(inOrder);
-        verifyTetherOffloadRuleAdd(inOrder,
-                UPSTREAM_IFINDEX2, UPSTREAM_IFACE_PARAMS2.macAddr, neighA, macA);
         verifyStartUpstreamIpv6Forwarding(inOrder, UPSTREAM_IFINDEX2);
         verifyTetherOffloadRuleAdd(inOrder,
+                UPSTREAM_IFINDEX2, UPSTREAM_IFACE_PARAMS2.macAddr, neighA, macA);
+        verifyTetherOffloadRuleAdd(inOrder,
                 UPSTREAM_IFINDEX2, UPSTREAM_IFACE_PARAMS2.macAddr, neighB, macB);
-        verifyNoUpstreamIpv6ForwardingChange(inOrder);
         resetNetdBpfMapAndCoordinator();
 
         // When the upstream is lost, rules are removed.
         dispatchTetherConnectionChanged(null, null, 0);
-        // Clear function is called two times by:
+        // Upstream clear function is called two times by:
         // - processMessage CMD_TETHER_CONNECTION_CHANGED for the upstream is lost.
         // - processMessage CMD_IPV6_TETHER_UPDATE for the IPv6 upstream is lost.
         // See dispatchTetherConnectionChanged.
-        verify(mBpfCoordinator, times(2)).tetherOffloadRuleClear(mIpServer);
+        verify(mBpfCoordinator, times(2)).updateAllIpv6Rules(
+                mIpServer, TEST_IFACE_PARAMS, NO_UPSTREAM);
+        verifyStopUpstreamIpv6Forwarding(inOrder);
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX2, UPSTREAM_IFACE_PARAMS2.macAddr, neighA, macA);
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX2, UPSTREAM_IFACE_PARAMS2.macAddr, neighB, macB);
-        verifyStopUpstreamIpv6Forwarding(inOrder);
+        // Upstream lost doesn't clear the downstream rules from BpfCoordinator.
+        // Do that here.
+        recvDelNeigh(myIfindex, neighA, NUD_STALE, macA);
+        recvDelNeigh(myIfindex, neighB, NUD_STALE, macB);
+        verify(mBpfCoordinator).removeIpv6DownstreamRule(
+                mIpServer,  makeDownstreamRule(NO_UPSTREAM, neighA, macNull));
+        verify(mBpfCoordinator).removeIpv6DownstreamRule(
+                mIpServer,  makeDownstreamRule(NO_UPSTREAM, neighB, macNull));
         resetNetdBpfMapAndCoordinator();
 
-        // If the upstream is IPv4-only, no rules are added.
+        // If the upstream is IPv4-only, no IPv6 rules are added to BPF map.
         dispatchTetherConnectionChanged(UPSTREAM_IFACE);
         resetNetdBpfMapAndCoordinator();
         recvNewNeigh(myIfindex, neighA, NUD_REACHABLE, macA);
-        // Clear function is called by #updateIpv6ForwardingRules for the IPv6 upstream is lost.
-        verify(mBpfCoordinator).tetherOffloadRuleClear(mIpServer);
         verifyNoUpstreamIpv6ForwardingChange(null);
+        // Downstream rules are only added to BpfCoordinator but not BPF map.
+        verify(mBpfCoordinator).addIpv6DownstreamRule(
+                mIpServer, makeDownstreamRule(NO_UPSTREAM, neighA, macA));
+        verifyNeverTetherOffloadRuleAdd();
         verifyNoMoreInteractions(mBpfCoordinator, mNetd, mBpfDownstream6Map, mBpfUpstream6Map);
 
-        // Rules can be added again once upstream IPv6 connectivity is available.
+        // Rules can be added again once upstream IPv6 connectivity is available. The existing rules
+        // with an upstream of NO_UPSTREAM are reapplied.
         lp.setInterfaceName(UPSTREAM_IFACE);
         dispatchTetherConnectionChanged(UPSTREAM_IFACE, lp, -1);
+        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
+        verify(mBpfCoordinator).addIpv6DownstreamRule(
+                mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighA, macA));
+        verifyTetherOffloadRuleAdd(null,
+                UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
         recvNewNeigh(myIfindex, neighB, NUD_REACHABLE, macB);
         verify(mBpfCoordinator).addIpv6DownstreamRule(
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighB, macB));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
-        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
-        verify(mBpfCoordinator, never()).addIpv6DownstreamRule(
-                mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighA, macA));
-        verifyNeverTetherOffloadRuleAdd(
-                UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
 
         // If upstream IPv6 connectivity is lost, rules are removed.
         resetNetdBpfMapAndCoordinator();
         dispatchTetherConnectionChanged(UPSTREAM_IFACE, null, 0);
-        verify(mBpfCoordinator).tetherOffloadRuleClear(mIpServer);
+        verify(mBpfCoordinator).updateAllIpv6Rules(mIpServer, TEST_IFACE_PARAMS, NO_UPSTREAM);
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
         verifyStopUpstreamIpv6Forwarding(null);
 
-        // When the interface goes down, rules are removed.
+        // When upstream IPv6 connectivity comes back, upstream rules are added and downstream rules
+        // are reapplied.
         lp.setInterfaceName(UPSTREAM_IFACE);
         dispatchTetherConnectionChanged(UPSTREAM_IFACE, lp, -1);
-        recvNewNeigh(myIfindex, neighA, NUD_REACHABLE, macA);
-        recvNewNeigh(myIfindex, neighB, NUD_REACHABLE, macB);
+        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
         verify(mBpfCoordinator).addIpv6DownstreamRule(
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighA, macA));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
-        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
         verify(mBpfCoordinator).addIpv6DownstreamRule(
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neighB, macB));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
         resetNetdBpfMapAndCoordinator();
 
+        // When the downstream interface goes down, rules are removed.
         mIpServer.stop();
         mLooper.dispatchAll();
-        verify(mBpfCoordinator).tetherOffloadRuleClear(mIpServer);
+        verify(mBpfCoordinator).clearAllIpv6Rules(mIpServer);
+        verifyStopUpstreamIpv6Forwarding(null);
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighA, macA);
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neighB, macB);
-        verifyStopUpstreamIpv6Forwarding(null);
         verify(mIpNeighborMonitor).stop();
         resetNetdBpfMapAndCoordinator();
     }
@@ -1228,7 +1253,6 @@
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neigh, macA));
         verifyTetherOffloadRuleAdd(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neigh, macA);
-        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX);
         resetNetdBpfMapAndCoordinator();
 
         recvDelNeigh(myIfindex, neigh, NUD_STALE, macA);
@@ -1236,7 +1260,14 @@
                 mIpServer, makeDownstreamRule(UPSTREAM_IFINDEX, neigh, macNull));
         verifyTetherOffloadRuleRemove(null,
                 UPSTREAM_IFINDEX, UPSTREAM_IFACE_PARAMS.macAddr, neigh, macNull);
-        verifyStopUpstreamIpv6Forwarding(null);
+        resetNetdBpfMapAndCoordinator();
+
+        // Upstream IPv6 connectivity change causes upstream rules change.
+        LinkProperties lp2 = new LinkProperties();
+        lp2.setInterfaceName(UPSTREAM_IFACE2);
+        dispatchTetherConnectionChanged(UPSTREAM_IFACE2, lp2, 0);
+        verify(mBpfCoordinator).updateAllIpv6Rules(mIpServer, TEST_IFACE_PARAMS, UPSTREAM_IFINDEX2);
+        verifyStartUpstreamIpv6Forwarding(null, UPSTREAM_IFINDEX2);
         resetNetdBpfMapAndCoordinator();
 
         // [2] Disable BPF offload.
@@ -1247,12 +1278,16 @@
 
         recvNewNeigh(myIfindex, neigh, NUD_REACHABLE, macA);
         verifyNeverTetherOffloadRuleAdd();
-        verifyNoUpstreamIpv6ForwardingChange(null);
         resetNetdBpfMapAndCoordinator();
 
         recvDelNeigh(myIfindex, neigh, NUD_STALE, macA);
         verifyNeverTetherOffloadRuleRemove();
+        resetNetdBpfMapAndCoordinator();
+
+        // Upstream IPv6 connectivity change doesn't cause the rule to be added or removed.
+        dispatchTetherConnectionChanged(UPSTREAM_IFACE2, lp2, 0);
         verifyNoUpstreamIpv6ForwardingChange(null);
+        verifyNeverTetherOffloadRuleRemove();
         resetNetdBpfMapAndCoordinator();
     }
 
diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
index 04eb430..601f587 100644
--- a/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
+++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/BpfCoordinatorTest.java
@@ -169,6 +169,8 @@
     private static final String UPSTREAM_IFACE = "rmnet0";
     private static final String UPSTREAM_XLAT_IFACE = "v4-rmnet0";
     private static final String UPSTREAM_IFACE2 = "wlan0";
+    private static final String DOWNSTREAM_IFACE = "downstream1";
+    private static final String DOWNSTREAM_IFACE2 = "downstream2";
 
     private static final MacAddress DOWNSTREAM_MAC = MacAddress.fromString("12:34:56:78:90:ab");
     private static final MacAddress DOWNSTREAM_MAC2 = MacAddress.fromString("ab:90:78:56:34:12");
@@ -213,6 +215,11 @@
     private static final InterfaceParams UPSTREAM_IFACE_PARAMS2 = new InterfaceParams(
             UPSTREAM_IFACE2, UPSTREAM_IFINDEX2, MacAddress.fromString("44:55:66:00:00:0c"),
             NetworkStackConstants.ETHER_MTU);
+    private static final InterfaceParams DOWNSTREAM_IFACE_PARAMS = new InterfaceParams(
+            DOWNSTREAM_IFACE, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC, NetworkStackConstants.ETHER_MTU);
+    private static final InterfaceParams DOWNSTREAM_IFACE_PARAMS2 = new InterfaceParams(
+            DOWNSTREAM_IFACE2, DOWNSTREAM_IFINDEX2, DOWNSTREAM_MAC2,
+            NetworkStackConstants.ETHER_MTU);
 
     private static final Map<Integer, UpstreamInformation> UPSTREAM_INFORMATIONS = Map.of(
             UPSTREAM_IFINDEX, new UpstreamInformation(UPSTREAM_IFACE_PARAMS,
@@ -640,24 +647,6 @@
         }
     }
 
-    private void verifyStartUpstreamIpv6Forwarding(@Nullable InOrder inOrder, int downstreamIfIndex,
-            MacAddress downstreamMac, int upstreamIfindex) throws Exception {
-        if (!mDeps.isAtLeastS()) return;
-        final TetherUpstream6Key key = new TetherUpstream6Key(downstreamIfIndex, downstreamMac, 0);
-        final Tether6Value value = new Tether6Value(upstreamIfindex,
-                MacAddress.ALL_ZEROS_ADDRESS, MacAddress.ALL_ZEROS_ADDRESS,
-                ETH_P_IPV6, NetworkStackConstants.ETHER_MTU);
-        verifyWithOrder(inOrder, mBpfUpstream6Map).insertEntry(key, value);
-    }
-
-    private void verifyStopUpstreamIpv6Forwarding(@Nullable InOrder inOrder, int downstreamIfIndex,
-            MacAddress downstreamMac)
-            throws Exception {
-        if (!mDeps.isAtLeastS()) return;
-        final TetherUpstream6Key key = new TetherUpstream6Key(downstreamIfIndex, downstreamMac, 0);
-        verifyWithOrder(inOrder, mBpfUpstream6Map).deleteEntry(key);
-    }
-
     private void verifyNoUpstreamIpv6ForwardingChange(@Nullable InOrder inOrder) throws Exception {
         if (!mDeps.isAtLeastS()) return;
         if (inOrder != null) {
@@ -671,6 +660,13 @@
         }
     }
 
+    private void verifyAddUpstreamRule(@Nullable InOrder inOrder,
+            @NonNull Ipv6UpstreamRule rule) throws Exception {
+        if (!mDeps.isAtLeastS()) return;
+        verifyWithOrder(inOrder, mBpfUpstream6Map).insertEntry(
+                rule.makeTetherUpstream6Key(), rule.makeTether6Value());
+    }
+
     private void verifyAddDownstreamRule(@Nullable InOrder inOrder,
             @NonNull Ipv6DownstreamRule rule) throws Exception {
         if (mDeps.isAtLeastS()) {
@@ -681,6 +677,11 @@
         }
     }
 
+    private void verifyNeverAddUpstreamRule() throws Exception {
+        if (!mDeps.isAtLeastS()) return;
+        verify(mBpfUpstream6Map, never()).insertEntry(any(), any());
+    }
+
     private void verifyNeverAddDownstreamRule() throws Exception {
         if (mDeps.isAtLeastS()) {
             verify(mBpfDownstream6Map, never()).updateEntry(any(), any());
@@ -689,6 +690,13 @@
         }
     }
 
+    private void verifyRemoveUpstreamRule(@Nullable InOrder inOrder,
+            @NonNull final Ipv6UpstreamRule rule) throws Exception {
+        if (!mDeps.isAtLeastS()) return;
+        verifyWithOrder(inOrder, mBpfUpstream6Map).deleteEntry(
+                rule.makeTetherUpstream6Key());
+    }
+
     private void verifyRemoveDownstreamRule(@Nullable InOrder inOrder,
             @NonNull final Ipv6DownstreamRule rule) throws Exception {
         if (mDeps.isAtLeastS()) {
@@ -699,6 +707,11 @@
         }
     }
 
+    private void verifyNeverRemoveUpstreamRule() throws Exception {
+        if (!mDeps.isAtLeastS()) return;
+        verify(mBpfUpstream6Map, never()).deleteEntry(any());
+    }
+
     private void verifyNeverRemoveDownstreamRule() throws Exception {
         if (mDeps.isAtLeastS()) {
             verify(mBpfDownstream6Map, never()).deleteEntry(any());
@@ -763,24 +776,31 @@
 
         final String mobileIface = "rmnet_data0";
         final Integer mobileIfIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         // InOrder is required because mBpfStatsMap may be accessed by both
         // BpfCoordinator#tetherOffloadRuleAdd and BpfCoordinator#tetherOffloadGetAndClearStats.
         // The #verifyTetherOffloadGetAndClearStats can't distinguish who has ever called
         // mBpfStatsMap#getValue and get a wrong calling count which counts all.
-        final InOrder inOrder = inOrder(mNetd, mBpfDownstream6Map, mBpfLimitMap, mBpfStatsMap);
-        final Ipv6DownstreamRule rule = buildTestDownstreamRule(mobileIfIndex, NEIGH_A, MAC_A);
-        coordinator.addIpv6DownstreamRule(mIpServer, rule);
-        verifyAddDownstreamRule(inOrder, rule);
+        final InOrder inOrder = inOrder(mNetd, mBpfUpstream6Map, mBpfDownstream6Map, mBpfLimitMap,
+                mBpfStatsMap);
+        final Ipv6UpstreamRule upstreamRule = buildTestUpstreamRule(
+                mobileIfIndex, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
+        final Ipv6DownstreamRule downstreamRule = buildTestDownstreamRule(
+                mobileIfIndex, NEIGH_A, MAC_A);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, mobileIfIndex);
         verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, QUOTA_UNLIMITED,
                 true /* isInit */);
+        verifyAddUpstreamRule(inOrder, upstreamRule);
+        coordinator.addIpv6DownstreamRule(mIpServer, downstreamRule);
+        verifyAddDownstreamRule(inOrder, downstreamRule);
 
-        // Removing the last rule on current upstream immediately sends the cleanup stuff to netd.
+        // Removing the last rule on current upstream immediately sends the cleanup stuff to BPF.
         updateStatsEntryForTetherOffloadGetAndClearStats(
                 buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0));
-        coordinator.removeIpv6DownstreamRule(mIpServer, rule);
-        verifyRemoveDownstreamRule(inOrder, rule);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, 0);
+        verifyRemoveDownstreamRule(inOrder, downstreamRule);
+        verifyRemoveUpstreamRule(inOrder, upstreamRule);
         verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex);
     }
 
@@ -806,7 +826,7 @@
 
         final String mobileIface = "rmnet_data0";
         final Integer mobileIfIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         updateStatsEntriesAndWaitForUpdate(new TetherStatsParcel[] {
                 buildTestTetherStatsParcel(mobileIfIndex, 1000, 100, 2000, 200)});
@@ -847,8 +867,8 @@
 
         // Add interface name to lookup table. In realistic case, the upstream interface name will
         // be added by IpServer when IpServer has received with a new IPv6 upstream update event.
-        coordinator.addUpstreamNameToLookupTable(wlanIfIndex, wlanIface);
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(wlanIfIndex, wlanIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         // [1] Both interface stats are changed.
         // Setup the tether stats of wlan and mobile interface. Note that move forward the time of
@@ -912,7 +932,7 @@
 
         final String mobileIface = "rmnet_data0";
         final Integer mobileIfIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         // Verify that set quota to 0 will immediately triggers a callback.
         mTetherStatsProvider.onSetAlert(0);
@@ -978,9 +998,10 @@
     }
 
     @NonNull
-    private static Ipv6UpstreamRule buildTestUpstreamRule(int upstreamIfindex) {
-        return new Ipv6UpstreamRule(upstreamIfindex, DOWNSTREAM_IFINDEX,
-                IPV6_ZERO_PREFIX, DOWNSTREAM_MAC, MacAddress.ALL_ZEROS_ADDRESS,
+    private static Ipv6UpstreamRule buildTestUpstreamRule(
+            int upstreamIfindex, int downstreamIfindex, @NonNull MacAddress inDstMac) {
+        return new Ipv6UpstreamRule(upstreamIfindex, downstreamIfindex,
+                IPV6_ZERO_PREFIX, inDstMac, MacAddress.ALL_ZEROS_ADDRESS,
                 MacAddress.ALL_ZEROS_ADDRESS);
     }
 
@@ -1027,17 +1048,18 @@
 
         final String mobileIface = "rmnet_data0";
         final int mobileIfIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         // [1] Default limit.
         // Set the unlimited quota as default if the service has never applied a data limit for a
         // given upstream. Note that the data limit only be applied on an upstream which has rules.
-        final Ipv6DownstreamRule rule = buildTestDownstreamRule(mobileIfIndex, NEIGH_A, MAC_A);
-        final InOrder inOrder = inOrder(mNetd, mBpfDownstream6Map, mBpfLimitMap, mBpfStatsMap);
-        coordinator.addIpv6DownstreamRule(mIpServer, rule);
-        verifyAddDownstreamRule(inOrder, rule);
+        final Ipv6UpstreamRule rule = buildTestUpstreamRule(
+                mobileIfIndex, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
+        final InOrder inOrder = inOrder(mNetd, mBpfUpstream6Map, mBpfLimitMap, mBpfStatsMap);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, mobileIfIndex);
         verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, QUOTA_UNLIMITED,
                 true /* isInit */);
+        verifyAddUpstreamRule(inOrder, rule);
         inOrder.verifyNoMoreInteractions();
 
         // [2] Specific limit.
@@ -1062,7 +1084,6 @@
         }
     }
 
-    // TODO: Test the case in which the rules are changed from different IpServer objects.
     @Test
     public void testSetDataLimitOnRule6Change() throws Exception {
         setupFunctioningNetdInterface();
@@ -1071,39 +1092,41 @@
 
         final String mobileIface = "rmnet_data0";
         final int mobileIfIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         // Applying a data limit to the current upstream does not take any immediate action.
         // The data limit could be only set on an upstream which has rules.
         final long limit = 12345;
-        final InOrder inOrder = inOrder(mNetd, mBpfDownstream6Map, mBpfLimitMap, mBpfStatsMap);
+        final InOrder inOrder = inOrder(mNetd, mBpfUpstream6Map, mBpfLimitMap, mBpfStatsMap);
         mTetherStatsProvider.onSetLimit(mobileIface, limit);
         waitForIdle();
         verifyNeverTetherOffloadSetInterfaceQuota(inOrder);
 
-        // Adding the first rule on current upstream immediately sends the quota to netd.
-        final Ipv6DownstreamRule ruleA = buildTestDownstreamRule(mobileIfIndex, NEIGH_A, MAC_A);
-        coordinator.addIpv6DownstreamRule(mIpServer, ruleA);
-        verifyAddDownstreamRule(inOrder, ruleA);
+        // Adding the first rule on current upstream immediately sends the quota to BPF.
+        final Ipv6UpstreamRule ruleA = buildTestUpstreamRule(
+                mobileIfIndex, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, mobileIfIndex);
         verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, limit, true /* isInit */);
+        verifyAddUpstreamRule(inOrder, ruleA);
         inOrder.verifyNoMoreInteractions();
 
-        // Adding the second rule on current upstream does not send the quota to netd.
-        final Ipv6DownstreamRule ruleB = buildTestDownstreamRule(mobileIfIndex, NEIGH_B, MAC_B);
-        coordinator.addIpv6DownstreamRule(mIpServer, ruleB);
-        verifyAddDownstreamRule(inOrder, ruleB);
+        // Adding the second rule on current upstream does not send the quota to BPF.
+        final Ipv6UpstreamRule ruleB = buildTestUpstreamRule(
+                mobileIfIndex, DOWNSTREAM_IFINDEX2, DOWNSTREAM_MAC2);
+        coordinator.updateAllIpv6Rules(mIpServer2, DOWNSTREAM_IFACE_PARAMS2, mobileIfIndex);
+        verifyAddUpstreamRule(inOrder, ruleB);
         verifyNeverTetherOffloadSetInterfaceQuota(inOrder);
 
-        // Removing the second rule on current upstream does not send the quota to netd.
-        coordinator.removeIpv6DownstreamRule(mIpServer, ruleB);
-        verifyRemoveDownstreamRule(inOrder, ruleB);
+        // Removing the second rule on current upstream does not send the quota to BPF.
+        coordinator.updateAllIpv6Rules(mIpServer2, DOWNSTREAM_IFACE_PARAMS2, 0);
+        verifyRemoveUpstreamRule(inOrder, ruleB);
         verifyNeverTetherOffloadSetInterfaceQuota(inOrder);
 
-        // Removing the last rule on current upstream immediately sends the cleanup stuff to netd.
+        // Removing the last rule on current upstream immediately sends the cleanup stuff to BPF.
         updateStatsEntryForTetherOffloadGetAndClearStats(
                 buildTestTetherStatsParcel(mobileIfIndex, 0, 0, 0, 0));
-        coordinator.removeIpv6DownstreamRule(mIpServer, ruleA);
-        verifyRemoveDownstreamRule(inOrder, ruleA);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, 0);
+        verifyRemoveUpstreamRule(inOrder, ruleA);
         verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex);
         inOrder.verifyNoMoreInteractions();
     }
@@ -1118,8 +1141,8 @@
         final String mobileIface = "rmnet_data0";
         final Integer ethIfIndex = 100;
         final Integer mobileIfIndex = 101;
-        coordinator.addUpstreamNameToLookupTable(ethIfIndex, ethIface);
-        coordinator.addUpstreamNameToLookupTable(mobileIfIndex, mobileIface);
+        coordinator.maybeAddUpstreamToLookupTable(ethIfIndex, ethIface);
+        coordinator.maybeAddUpstreamToLookupTable(mobileIfIndex, mobileIface);
 
         final InOrder inOrder = inOrder(mNetd, mBpfDownstream6Map, mBpfUpstream6Map, mBpfLimitMap,
                 mBpfStatsMap);
@@ -1133,20 +1156,25 @@
 
         // [1] Adding rules on the upstream Ethernet.
         // Note that the default data limit is applied after the first rule is added.
+        final Ipv6UpstreamRule ethernetUpstreamRule = buildTestUpstreamRule(
+                ethIfIndex, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
         final Ipv6DownstreamRule ethernetRuleA = buildTestDownstreamRule(
                 ethIfIndex, NEIGH_A, MAC_A);
         final Ipv6DownstreamRule ethernetRuleB = buildTestDownstreamRule(
                 ethIfIndex, NEIGH_B, MAC_B);
 
-        coordinator.addIpv6DownstreamRule(mIpServer, ethernetRuleA);
-        verifyAddDownstreamRule(inOrder, ethernetRuleA);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, ethIfIndex);
         verifyTetherOffloadSetInterfaceQuota(inOrder, ethIfIndex, QUOTA_UNLIMITED,
                 true /* isInit */);
-        verifyStartUpstreamIpv6Forwarding(inOrder, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC, ethIfIndex);
+        verifyAddUpstreamRule(inOrder, ethernetUpstreamRule);
+        coordinator.addIpv6DownstreamRule(mIpServer, ethernetRuleA);
+        verifyAddDownstreamRule(inOrder, ethernetRuleA);
         coordinator.addIpv6DownstreamRule(mIpServer, ethernetRuleB);
         verifyAddDownstreamRule(inOrder, ethernetRuleB);
 
         // [2] Update the existing rules from Ethernet to cellular.
+        final Ipv6UpstreamRule mobileUpstreamRule = buildTestUpstreamRule(
+                mobileIfIndex, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
         final Ipv6DownstreamRule mobileRuleA = buildTestDownstreamRule(
                 mobileIfIndex, NEIGH_A, MAC_A);
         final Ipv6DownstreamRule mobileRuleB = buildTestDownstreamRule(
@@ -1156,25 +1184,24 @@
 
         // Update the existing rules for upstream changes. The rules are removed and re-added one
         // by one for updating upstream interface index by #tetherOffloadRuleUpdate.
-        coordinator.tetherOffloadRuleUpdate(mIpServer, mobileIfIndex);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, mobileIfIndex);
         verifyRemoveDownstreamRule(inOrder, ethernetRuleA);
         verifyRemoveDownstreamRule(inOrder, ethernetRuleB);
-        verifyStopUpstreamIpv6Forwarding(inOrder, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
+        verifyRemoveUpstreamRule(inOrder, ethernetUpstreamRule);
         verifyTetherOffloadGetAndClearStats(inOrder, ethIfIndex);
-        verifyAddDownstreamRule(inOrder, mobileRuleA);
         verifyTetherOffloadSetInterfaceQuota(inOrder, mobileIfIndex, QUOTA_UNLIMITED,
                 true /* isInit */);
-        verifyStartUpstreamIpv6Forwarding(inOrder, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC,
-                mobileIfIndex);
+        verifyAddUpstreamRule(inOrder, mobileUpstreamRule);
+        verifyAddDownstreamRule(inOrder, mobileRuleA);
         verifyAddDownstreamRule(inOrder, mobileRuleB);
 
         // [3] Clear all rules for a given IpServer.
         updateStatsEntryForTetherOffloadGetAndClearStats(
                 buildTestTetherStatsParcel(mobileIfIndex, 50, 60, 70, 80));
-        coordinator.tetherOffloadRuleClear(mIpServer);
+        coordinator.clearAllIpv6Rules(mIpServer);
         verifyRemoveDownstreamRule(inOrder, mobileRuleA);
         verifyRemoveDownstreamRule(inOrder, mobileRuleB);
-        verifyStopUpstreamIpv6Forwarding(inOrder, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
+        verifyRemoveUpstreamRule(inOrder, mobileUpstreamRule);
         verifyTetherOffloadGetAndClearStats(inOrder, mobileIfIndex);
 
         // [4] Force pushing stats update to verify that the last diff of stats is reported on all
@@ -1204,7 +1231,7 @@
         // The interface name lookup table can't be added.
         final String iface = "rmnet_data0";
         final Integer ifIndex = 100;
-        coordinator.addUpstreamNameToLookupTable(ifIndex, iface);
+        coordinator.maybeAddUpstreamToLookupTable(ifIndex, iface);
         assertEquals(0, coordinator.getInterfaceNamesForTesting().size());
 
         // The rule can't be added.
@@ -1230,14 +1257,15 @@
         assertEquals(1, rules.size());
 
         // The rule can't be cleared.
-        coordinator.tetherOffloadRuleClear(mIpServer);
+        coordinator.clearAllIpv6Rules(mIpServer);
         verifyNeverRemoveDownstreamRule();
         rules = coordinator.getIpv6DownstreamRulesForTesting().get(mIpServer);
         assertNotNull(rules);
         assertEquals(1, rules.size());
 
         // The rule can't be updated.
-        coordinator.tetherOffloadRuleUpdate(mIpServer, rule.upstreamIfindex + 1 /* new */);
+        coordinator.updateAllIpv6Rules(
+                mIpServer, DOWNSTREAM_IFACE_PARAMS, rule.upstreamIfindex + 1 /* new */);
         verifyNeverRemoveDownstreamRule();
         verifyNeverAddDownstreamRule();
         rules = coordinator.getIpv6DownstreamRulesForTesting().get(mIpServer);
@@ -1552,7 +1580,7 @@
         // interface index.
         doReturn(upstreamInfo.interfaceParams).when(mDeps).getInterfaceParams(
                 upstreamInfo.interfaceParams.name);
-        coordinator.addUpstreamNameToLookupTable(upstreamInfo.interfaceParams.index,
+        coordinator.maybeAddUpstreamToLookupTable(upstreamInfo.interfaceParams.index,
                 upstreamInfo.interfaceParams.name);
 
         final LinkProperties lp = new LinkProperties();
@@ -1677,19 +1705,21 @@
     public void testAddDevMapRule6() throws Exception {
         final BpfCoordinator coordinator = makeBpfCoordinator();
 
-        coordinator.addUpstreamNameToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
-        final Ipv6DownstreamRule ruleA = buildTestDownstreamRule(UPSTREAM_IFINDEX, NEIGH_A, MAC_A);
-        final Ipv6DownstreamRule ruleB = buildTestDownstreamRule(UPSTREAM_IFINDEX, NEIGH_B, MAC_B);
-
-        coordinator.addIpv6DownstreamRule(mIpServer, ruleA);
+        coordinator.maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
+        coordinator.updateAllIpv6Rules(mIpServer, DOWNSTREAM_IFACE_PARAMS, UPSTREAM_IFINDEX);
         verify(mBpfDevMap).updateEntry(eq(new TetherDevKey(UPSTREAM_IFINDEX)),
                 eq(new TetherDevValue(UPSTREAM_IFINDEX)));
         verify(mBpfDevMap).updateEntry(eq(new TetherDevKey(DOWNSTREAM_IFINDEX)),
                 eq(new TetherDevValue(DOWNSTREAM_IFINDEX)));
         clearInvocations(mBpfDevMap);
 
-        coordinator.addIpv6DownstreamRule(mIpServer, ruleB);
-        verify(mBpfDevMap, never()).updateEntry(any(), any());
+        // Adding the second downstream, only the second downstream ifindex is added to DevMap,
+        // the existing upstream ifindex won't be added again.
+        coordinator.updateAllIpv6Rules(mIpServer2, DOWNSTREAM_IFACE_PARAMS2, UPSTREAM_IFINDEX);
+        verify(mBpfDevMap).updateEntry(eq(new TetherDevKey(DOWNSTREAM_IFINDEX2)),
+                eq(new TetherDevValue(DOWNSTREAM_IFINDEX2)));
+        verify(mBpfDevMap, never()).updateEntry(eq(new TetherDevKey(UPSTREAM_IFINDEX)),
+                eq(new TetherDevValue(UPSTREAM_IFINDEX)));
     }
 
     @Test
@@ -2153,7 +2183,8 @@
         assertEquals("upstreamIfindex: 1001, downstreamIfindex: 2001, address: 2001:db8::1, "
                 + "srcMac: 12:34:56:78:90:ab, dstMac: 00:00:00:00:00:0a",
                 downstreamRule.toString());
-        final Ipv6UpstreamRule upstreamRule = buildTestUpstreamRule(UPSTREAM_IFINDEX);
+        final Ipv6UpstreamRule upstreamRule = buildTestUpstreamRule(
+                UPSTREAM_IFINDEX, DOWNSTREAM_IFINDEX, DOWNSTREAM_MAC);
         assertEquals("upstreamIfindex: 1001, downstreamIfindex: 2001, sourcePrefix: ::/64, "
                 + "inDstMac: 12:34:56:78:90:ab, outSrcMac: 00:00:00:00:00:00, "
                 + "outDstMac: 00:00:00:00:00:00", upstreamRule.toString());
@@ -2221,7 +2252,7 @@
                         0L /* txPackets */, 0L /* txBytes */, 0L /* txErrors */));
 
         // dumpDevmap
-        coordinator.addUpstreamNameToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
+        coordinator.maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
         mBpfDevMap.insertEntry(
                 new TetherDevKey(UPSTREAM_IFINDEX),
                 new TetherDevValue(UPSTREAM_IFINDEX));
@@ -2390,7 +2421,7 @@
         // +-------+-------+-------+-------+-------+
 
         // [1] Mobile IPv4 only
-        coordinator.addUpstreamNameToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
+        coordinator.maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX, UPSTREAM_IFACE);
         doReturn(UPSTREAM_IFACE_PARAMS).when(mDeps).getInterfaceParams(UPSTREAM_IFACE);
         final UpstreamNetworkState mobileIPv4UpstreamState = new UpstreamNetworkState(
                 buildUpstreamLinkProperties(UPSTREAM_IFACE,
@@ -2442,7 +2473,7 @@
         verifyIpv4Upstream(ipv4UpstreamIndices, interfaceNames);
 
         // Mobile IPv6 and xlat
-        // IpServer doesn't add xlat interface mapping via #addUpstreamNameToLookupTable on
+        // IpServer doesn't add xlat interface mapping via #maybeAddUpstreamToLookupTable on
         // S and T devices.
         coordinator.updateUpstreamNetworkState(mobile464xlatUpstreamState);
         // Upstream IPv4 address mapping is removed because xlat interface is not supported.
@@ -2457,7 +2488,7 @@
 
         // [6] Wifi IPv4 and IPv6
         // Expect that upstream index map is cleared because ether ip is not supported.
-        coordinator.addUpstreamNameToLookupTable(UPSTREAM_IFINDEX2, UPSTREAM_IFACE2);
+        coordinator.maybeAddUpstreamToLookupTable(UPSTREAM_IFINDEX2, UPSTREAM_IFACE2);
         doReturn(UPSTREAM_IFACE_PARAMS2).when(mDeps).getInterfaceParams(UPSTREAM_IFACE2);
         final UpstreamNetworkState wifiDualStackUpstreamState = new UpstreamNetworkState(
                 buildUpstreamLinkProperties(UPSTREAM_IFACE2,
diff --git a/netbpfload/NetBpfLoad.cpp b/netbpfload/NetBpfLoad.cpp
new file mode 100644
index 0000000..99a2ab4
--- /dev/null
+++ b/netbpfload/NetBpfLoad.cpp
@@ -0,0 +1,352 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef LOG_TAG
+#define LOG_TAG "bpfloader"
+#endif
+
+#include <arpa/inet.h>
+#include <dirent.h>
+#include <elf.h>
+#include <error.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <linux/bpf.h>
+#include <linux/unistd.h>
+#include <net/if.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <android-base/logging.h>
+#include <android-base/macros.h>
+#include <android-base/properties.h>
+#include <android-base/stringprintf.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <libbpf_android.h>
+#include <log/log.h>
+#include <netdutils/Misc.h>
+#include <netdutils/Slice.h>
+#include "BpfSyscallWrappers.h"
+#include "bpf/BpfUtils.h"
+
+using android::base::EndsWith;
+using android::bpf::domain;
+using std::string;
+
+bool exists(const char* const path) {
+    int v = access(path, F_OK);
+    if (!v) {
+        ALOGI("%s exists.", path);
+        return true;
+    }
+    if (errno == ENOENT) return false;
+    ALOGE("FATAL: access(%s, F_OK) -> %d [%d:%s]", path, v, errno, strerror(errno));
+    abort();  // can only hit this if permissions (likely selinux) are screwed up
+}
+
+constexpr unsigned long long kTetheringApexDomainBitmask =
+        domainToBitmask(domain::tethering) |
+        domainToBitmask(domain::net_private) |
+        domainToBitmask(domain::net_shared) |
+        domainToBitmask(domain::netd_readonly) |
+        domainToBitmask(domain::netd_shared);
+
+// Programs shipped inside the tethering apex should be limited to networking stuff,
+// as KPROBE, PERF_EVENT, TRACEPOINT are dangerous to use from mainline updatable code,
+// since they are less stable abi/api and may conflict with platform uses of bpf.
+constexpr bpf_prog_type kTetheringApexAllowedProgTypes[] = {
+        BPF_PROG_TYPE_CGROUP_SKB,
+        BPF_PROG_TYPE_CGROUP_SOCK,
+        BPF_PROG_TYPE_CGROUP_SOCKOPT,
+        BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
+        BPF_PROG_TYPE_CGROUP_SYSCTL,
+        BPF_PROG_TYPE_LWT_IN,
+        BPF_PROG_TYPE_LWT_OUT,
+        BPF_PROG_TYPE_LWT_SEG6LOCAL,
+        BPF_PROG_TYPE_LWT_XMIT,
+        BPF_PROG_TYPE_SCHED_ACT,
+        BPF_PROG_TYPE_SCHED_CLS,
+        BPF_PROG_TYPE_SOCKET_FILTER,
+        BPF_PROG_TYPE_SOCK_OPS,
+        BPF_PROG_TYPE_XDP,
+};
+
+// Networking-related program types are limited to the Tethering Apex
+// to prevent things from breaking due to conflicts on mainline updates
+// (exception made for socket filters, ie. xt_bpf for potential use in iptables,
+// or for attaching to sockets directly)
+constexpr bpf_prog_type kPlatformAllowedProgTypes[] = {
+        BPF_PROG_TYPE_KPROBE,
+        BPF_PROG_TYPE_PERF_EVENT,
+        BPF_PROG_TYPE_SOCKET_FILTER,
+        BPF_PROG_TYPE_TRACEPOINT,
+        BPF_PROG_TYPE_UNSPEC,  // Will be replaced with fuse bpf program type
+};
+
+// see b/162057235. For arbitrary program types, the concern is that due to the lack of
+// SELinux access controls over BPF program attachpoints, we have no way to control the
+// attachment of programs to shared resources (or to detect when a shared resource
+// has one BPF program replace another that is attached there)
+constexpr bpf_prog_type kVendorAllowedProgTypes[] = {
+        BPF_PROG_TYPE_SOCKET_FILTER,
+};
+
+
+const android::bpf::Location locations[] = {
+        // S+ Tethering mainline module (network_stack): tether offload
+        {
+                .dir = "/apex/com.android.tethering/etc/bpf/",
+                .prefix = "tethering/",
+                .allowedDomainBitmask = kTetheringApexDomainBitmask,
+                .allowedProgTypes = kTetheringApexAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kTetheringApexAllowedProgTypes),
+        },
+        // T+ Tethering mainline module (shared with netd & system server)
+        // netutils_wrapper (for iptables xt_bpf) has access to programs
+        {
+                .dir = "/apex/com.android.tethering/etc/bpf/netd_shared/",
+                .prefix = "netd_shared/",
+                .allowedDomainBitmask = kTetheringApexDomainBitmask,
+                .allowedProgTypes = kTetheringApexAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kTetheringApexAllowedProgTypes),
+        },
+        // T+ Tethering mainline module (shared with netd & system server)
+        // netutils_wrapper has no access, netd has read only access
+        {
+                .dir = "/apex/com.android.tethering/etc/bpf/netd_readonly/",
+                .prefix = "netd_readonly/",
+                .allowedDomainBitmask = kTetheringApexDomainBitmask,
+                .allowedProgTypes = kTetheringApexAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kTetheringApexAllowedProgTypes),
+        },
+        // T+ Tethering mainline module (shared with system server)
+        {
+                .dir = "/apex/com.android.tethering/etc/bpf/net_shared/",
+                .prefix = "net_shared/",
+                .allowedDomainBitmask = kTetheringApexDomainBitmask,
+                .allowedProgTypes = kTetheringApexAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kTetheringApexAllowedProgTypes),
+        },
+        // T+ Tethering mainline module (not shared, just network_stack)
+        {
+                .dir = "/apex/com.android.tethering/etc/bpf/net_private/",
+                .prefix = "net_private/",
+                .allowedDomainBitmask = kTetheringApexDomainBitmask,
+                .allowedProgTypes = kTetheringApexAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kTetheringApexAllowedProgTypes),
+        },
+        // Core operating system
+        {
+                .dir = "/system/etc/bpf/",
+                .prefix = "",
+                .allowedDomainBitmask = domainToBitmask(domain::platform),
+                .allowedProgTypes = kPlatformAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kPlatformAllowedProgTypes),
+        },
+        // Vendor operating system
+        {
+                .dir = "/vendor/etc/bpf/",
+                .prefix = "vendor/",
+                .allowedDomainBitmask = domainToBitmask(domain::vendor),
+                .allowedProgTypes = kVendorAllowedProgTypes,
+                .allowedProgTypesLength = arraysize(kVendorAllowedProgTypes),
+        },
+};
+
+int loadAllElfObjects(const android::bpf::Location& location) {
+    int retVal = 0;
+    DIR* dir;
+    struct dirent* ent;
+
+    if ((dir = opendir(location.dir)) != NULL) {
+        while ((ent = readdir(dir)) != NULL) {
+            string s = ent->d_name;
+            if (!EndsWith(s, ".o")) continue;
+
+            string progPath(location.dir);
+            progPath += s;
+
+            bool critical;
+            int ret = android::bpf::loadProg(progPath.c_str(), &critical, location);
+            if (ret) {
+                if (critical) retVal = ret;
+                ALOGE("Failed to load object: %s, ret: %s", progPath.c_str(), std::strerror(-ret));
+            } else {
+                ALOGI("Loaded object: %s", progPath.c_str());
+            }
+        }
+        closedir(dir);
+    }
+    return retVal;
+}
+
+int createSysFsBpfSubDir(const char* const prefix) {
+    if (*prefix) {
+        mode_t prevUmask = umask(0);
+
+        string s = "/sys/fs/bpf/";
+        s += prefix;
+
+        errno = 0;
+        int ret = mkdir(s.c_str(), S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO);
+        if (ret && errno != EEXIST) {
+            const int err = errno;
+            ALOGE("Failed to create directory: %s, ret: %s", s.c_str(), std::strerror(err));
+            return -err;
+        }
+
+        umask(prevUmask);
+    }
+    return 0;
+}
+
+// Technically 'value' doesn't need to be newline terminated, but it's best
+// to include a newline to match 'echo "value" > /proc/sys/...foo' behaviour,
+// which is usually how kernel devs test the actual sysctl interfaces.
+int writeProcSysFile(const char *filename, const char *value) {
+    android::base::unique_fd fd(open(filename, O_WRONLY | O_CLOEXEC));
+    if (fd < 0) {
+        const int err = errno;
+        ALOGE("open('%s', O_WRONLY | O_CLOEXEC) -> %s", filename, strerror(err));
+        return -err;
+    }
+    int len = strlen(value);
+    int v = write(fd, value, len);
+    if (v < 0) {
+        const int err = errno;
+        ALOGE("write('%s', '%s', %d) -> %s", filename, value, len, strerror(err));
+        return -err;
+    }
+    if (v != len) {
+        // In practice, due to us only using this for /proc/sys/... files, this can't happen.
+        ALOGE("write('%s', '%s', %d) -> short write [%d]", filename, value, len, v);
+        return -EINVAL;
+    }
+    return 0;
+}
+
+int main(int argc, char** argv) {
+    (void)argc;
+    android::base::InitLogging(argv, &android::base::KernelLogger);
+
+    if (!android::bpf::isAtLeastKernelVersion(4, 19, 0)) {
+        ALOGE("Android U QPR2 requires kernel 4.19.");
+        return 1;
+    }
+
+    if (android::bpf::isUserspace32bit() && android::bpf::isAtLeastKernelVersion(6, 2, 0)) {
+        /* Android 14/U should only launch on 64-bit kernels
+         *   T launches on 5.10/5.15
+         *   U launches on 5.15/6.1
+         * So >=5.16 implies isKernel64Bit()
+         *
+         * We thus added a test to V VTS which requires 5.16+ devices to use 64-bit kernels.
+         *
+         * Starting with Android V, which is the first to support a post 6.1 Linux Kernel,
+         * we also require 64-bit userspace.
+         *
+         * There are various known issues with 32-bit userspace talking to various
+         * kernel interfaces (especially CAP_NET_ADMIN ones) on a 64-bit kernel.
+         * Some of these have userspace or kernel workarounds/hacks.
+         * Some of them don't...
+         * We're going to be removing the hacks.
+         *
+         * Additionally the 32-bit kernel jit support is poor,
+         * and 32-bit userspace on 64-bit kernel bpf ringbuffer compatibility is broken.
+         */
+        ALOGE("64-bit userspace required on 6.2+ kernels.");
+        return 1;
+    }
+
+    // Ensure we can determine the Android build type.
+    if (!android::bpf::isEng() && !android::bpf::isUser() && !android::bpf::isUserdebug()) {
+        ALOGE("Failed to determine the build type: got %s, want 'eng', 'user', or 'userdebug'",
+              android::bpf::getBuildType().c_str());
+        return 1;
+    }
+
+    // Linux 5.16-rc1 changed the default to 2 (disabled but changeable), but we need 0 (enabled)
+    // (this writeFile is known to fail on at least 4.19, but always defaults to 0 on pre-5.13,
+    // on 5.13+ it depends on CONFIG_BPF_UNPRIV_DEFAULT_OFF)
+    if (writeProcSysFile("/proc/sys/kernel/unprivileged_bpf_disabled", "0\n") &&
+        android::bpf::isAtLeastKernelVersion(5, 13, 0)) return 1;
+
+    // Enable the eBPF JIT -- but do note that on 64-bit kernels it is likely
+    // already force enabled by the kernel config option BPF_JIT_ALWAYS_ON.
+    // (Note: this (open) will fail with ENOENT 'No such file or directory' if
+    //  kernel does not have CONFIG_BPF_JIT=y)
+    // BPF_JIT is required by R VINTF (which means 4.14/4.19/5.4 kernels),
+    // but 4.14/4.19 were released with P & Q, and only 5.4 is new in R+.
+    if (writeProcSysFile("/proc/sys/net/core/bpf_jit_enable", "1\n")) return 1;
+
+    // Enable JIT kallsyms export for privileged users only
+    // (Note: this (open) will fail with ENOENT 'No such file or directory' if
+    //  kernel does not have CONFIG_HAVE_EBPF_JIT=y)
+    if (writeProcSysFile("/proc/sys/net/core/bpf_jit_kallsyms", "1\n")) return 1;
+
+    // Create all the pin subdirectories
+    // (this must be done first to allow selinux_context and pin_subdir functionality,
+    //  which could otherwise fail with ENOENT during object pinning or renaming,
+    //  due to ordering issues)
+    for (const auto& location : locations) {
+        if (createSysFsBpfSubDir(location.prefix)) return 1;
+    }
+
+    // Note: there's no actual src dir for fs_bpf_loader .o's,
+    // so it is not listed in 'locations[].prefix'.
+    // This is because this is primarily meant for triggering genfscon rules,
+    // and as such this will likely always be the case.
+    // Thus we need to manually create the /sys/fs/bpf/loader subdirectory.
+    if (createSysFsBpfSubDir("loader")) return 1;
+
+    // Load all ELF objects, create programs and maps, and pin them
+    for (const auto& location : locations) {
+        if (loadAllElfObjects(location) != 0) {
+            ALOGE("=== CRITICAL FAILURE LOADING BPF PROGRAMS FROM %s ===", location.dir);
+            ALOGE("If this triggers reliably, you're probably missing kernel options or patches.");
+            ALOGE("If this triggers randomly, you might be hitting some memory allocation "
+                  "problems or startup script race.");
+            ALOGE("--- DO NOT EXPECT SYSTEM TO BOOT SUCCESSFULLY ---");
+            sleep(20);
+            return 2;
+        }
+    }
+
+    int key = 1;
+    int value = 123;
+    android::base::unique_fd map(
+            android::bpf::createMap(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2, 0));
+    if (android::bpf::writeToMapEntry(map, &key, &value, BPF_ANY)) {
+        ALOGE("Critical kernel bug - failure to write into index 1 of 2 element bpf map array.");
+        return 1;
+    }
+
+    if (android::base::SetProperty("bpf.progs_loaded", "1") == false) {
+        ALOGE("Failed to set bpf.progs_loaded property");
+        return 1;
+    }
+
+    return 0;
+}
diff --git a/netbpfload/loader.cpp b/netbpfload/loader.cpp
new file mode 100644
index 0000000..d817614
--- /dev/null
+++ b/netbpfload/loader.cpp
@@ -0,0 +1,1249 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "LibBpfLoader"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/bpf.h>
+#include <linux/elf.h>
+#include <log/log.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <sys/stat.h>
+#include <sys/utsname.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+// This is BpfLoader v0.41
+// WARNING: If you ever hit cherrypick conflicts here you're doing it wrong:
+// You are NOT allowed to cherrypick bpfloader related patches out of order.
+// (indeed: cherrypicking is probably a bad idea and you should merge instead)
+// Mainline supports ONLY the published versions of the bpfloader for each Android release.
+#define BPFLOADER_VERSION_MAJOR 0u
+#define BPFLOADER_VERSION_MINOR 41u
+#define BPFLOADER_VERSION ((BPFLOADER_VERSION_MAJOR << 16) | BPFLOADER_VERSION_MINOR)
+
+#include "BpfSyscallWrappers.h"
+#include "bpf/BpfUtils.h"
+#include "bpf/bpf_map_def.h"
+#include "include/libbpf_android.h"
+
+#if BPFLOADER_VERSION < COMPILE_FOR_BPFLOADER_VERSION
+#error "BPFLOADER_VERSION is less than COMPILE_FOR_BPFLOADER_VERSION"
+#endif
+
+#include <cstdlib>
+#include <fstream>
+#include <iostream>
+#include <optional>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include <android-base/cmsg.h>
+#include <android-base/file.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <cutils/properties.h>
+
+#define BPF_FS_PATH "/sys/fs/bpf/"
+
+// Size of the BPF log buffer for verifier logging
+#define BPF_LOAD_LOG_SZ 0xfffff
+
+// Unspecified attach type is 0 which is BPF_CGROUP_INET_INGRESS.
+#define BPF_ATTACH_TYPE_UNSPEC BPF_CGROUP_INET_INGRESS
+
+using android::base::StartsWith;
+using android::base::unique_fd;
+using std::ifstream;
+using std::ios;
+using std::optional;
+using std::string;
+using std::vector;
+
+static std::string getBuildTypeInternal() {
+    char value[PROPERTY_VALUE_MAX] = {};
+    (void)property_get("ro.build.type", value, "unknown");  // ignore length
+    return value;
+}
+
+namespace android {
+namespace bpf {
+
+const std::string& getBuildType() {
+    static std::string t = getBuildTypeInternal();
+    return t;
+}
+
+static unsigned int page_size = static_cast<unsigned int>(getpagesize());
+
+constexpr const char* lookupSelinuxContext(const domain d, const char* const unspecified = "") {
+    switch (d) {
+        case domain::unspecified:   return unspecified;
+        case domain::platform:      return "fs_bpf";
+        case domain::tethering:     return "fs_bpf_tethering";
+        case domain::net_private:   return "fs_bpf_net_private";
+        case domain::net_shared:    return "fs_bpf_net_shared";
+        case domain::netd_readonly: return "fs_bpf_netd_readonly";
+        case domain::netd_shared:   return "fs_bpf_netd_shared";
+        case domain::vendor:        return "fs_bpf_vendor";
+        case domain::loader:        return "fs_bpf_loader";
+        default:                    return "(unrecognized)";
+    }
+}
+
+domain getDomainFromSelinuxContext(const char s[BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE]) {
+    for (domain d : AllDomains) {
+        // Not sure how to enforce this at compile time, so abort() bpfloader at boot instead
+        if (strlen(lookupSelinuxContext(d)) >= BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE) abort();
+        if (!strncmp(s, lookupSelinuxContext(d), BPF_SELINUX_CONTEXT_CHAR_ARRAY_SIZE)) return d;
+    }
+    ALOGW("ignoring unrecognized selinux_context '%-32s'", s);
+    // We should return 'unrecognized' here, however: returning unspecified will
+    // result in the system simply using the default context, which in turn
+    // will allow future expansion by adding more restrictive selinux types.
+    // Older bpfloader will simply ignore that, and use the less restrictive default.
+    // This does mean you CANNOT later add a *less* restrictive type than the default.
+    //
+    // Note: we cannot just abort() here as this might be a mainline module shipped optional update
+    return domain::unspecified;
+}
+
+constexpr const char* lookupPinSubdir(const domain d, const char* const unspecified = "") {
+    switch (d) {
+        case domain::unspecified:   return unspecified;
+        case domain::platform:      return "/";
+        case domain::tethering:     return "tethering/";
+        case domain::net_private:   return "net_private/";
+        case domain::net_shared:    return "net_shared/";
+        case domain::netd_readonly: return "netd_readonly/";
+        case domain::netd_shared:   return "netd_shared/";
+        case domain::vendor:        return "vendor/";
+        case domain::loader:        return "loader/";
+        default:                    return "(unrecognized)";
+    }
+};
+
+domain getDomainFromPinSubdir(const char s[BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE]) {
+    for (domain d : AllDomains) {
+        // Not sure how to enforce this at compile time, so abort() bpfloader at boot instead
+        if (strlen(lookupPinSubdir(d)) >= BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE) abort();
+        if (!strncmp(s, lookupPinSubdir(d), BPF_PIN_SUBDIR_CHAR_ARRAY_SIZE)) return d;
+    }
+    ALOGE("unrecognized pin_subdir '%-32s'", s);
+    // pin_subdir affects the object's full pathname,
+    // and thus using the default would change the location and thus our code's ability to find it,
+    // hence this seems worth treating as a true error condition.
+    //
+    // Note: we cannot just abort() here as this might be a mainline module shipped optional update
+    // However, our callers will treat this as an error, and stop loading the specific .o,
+    // which will fail bpfloader if the .o is marked critical.
+    return domain::unrecognized;
+}
+
+static string pathToObjName(const string& path) {
+    // extract everything after the final slash, ie. this is the filename 'foo@1.o' or 'bar.o'
+    string filename = android::base::Split(path, "/").back();
+    // strip off everything from the final period onwards (strip '.o' suffix), ie. 'foo@1' or 'bar'
+    string name = filename.substr(0, filename.find_last_of('.'));
+    // strip any potential @1 suffix, this will leave us with just 'foo' or 'bar'
+    // this can be used to provide duplicate programs (mux based on the bpfloader version)
+    return name.substr(0, name.find_last_of('@'));
+}
+
+typedef struct {
+    const char* name;
+    enum bpf_prog_type type;
+    enum bpf_attach_type expected_attach_type;
+} sectionType;
+
+/*
+ * Map section name prefixes to program types, the section name will be:
+ *   SECTION(<prefix>/<name-of-program>)
+ * For example:
+ *   SECTION("tracepoint/sched_switch_func") where sched_switch_funcs
+ * is the name of the program, and tracepoint is the type.
+ *
+ * However, be aware that you should not be directly using the SECTION() macro.
+ * Instead use the DEFINE_(BPF|XDP)_(PROG|MAP)... & LICENSE/CRITICAL macros.
+ */
+sectionType sectionNameTypes[] = {
+        {"bind4/",         BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_BIND},
+        {"bind6/",         BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_BIND},
+        {"cgroupskb/",     BPF_PROG_TYPE_CGROUP_SKB,       BPF_ATTACH_TYPE_UNSPEC},
+        {"cgroupsock/",    BPF_PROG_TYPE_CGROUP_SOCK,      BPF_ATTACH_TYPE_UNSPEC},
+        {"connect4/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET4_CONNECT},
+        {"connect6/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_INET6_CONNECT},
+        {"egress/",        BPF_PROG_TYPE_CGROUP_SKB,       BPF_CGROUP_INET_EGRESS},
+        {"getsockopt/",    BPF_PROG_TYPE_CGROUP_SOCKOPT,   BPF_CGROUP_GETSOCKOPT},
+        {"ingress/",       BPF_PROG_TYPE_CGROUP_SKB,       BPF_CGROUP_INET_INGRESS},
+        {"kprobe/",        BPF_PROG_TYPE_KPROBE,           BPF_ATTACH_TYPE_UNSPEC},
+        {"kretprobe/",     BPF_PROG_TYPE_KPROBE,           BPF_ATTACH_TYPE_UNSPEC},
+        {"lwt_in/",        BPF_PROG_TYPE_LWT_IN,           BPF_ATTACH_TYPE_UNSPEC},
+        {"lwt_out/",       BPF_PROG_TYPE_LWT_OUT,          BPF_ATTACH_TYPE_UNSPEC},
+        {"lwt_seg6local/", BPF_PROG_TYPE_LWT_SEG6LOCAL,    BPF_ATTACH_TYPE_UNSPEC},
+        {"lwt_xmit/",      BPF_PROG_TYPE_LWT_XMIT,         BPF_ATTACH_TYPE_UNSPEC},
+        {"perf_event/",    BPF_PROG_TYPE_PERF_EVENT,       BPF_ATTACH_TYPE_UNSPEC},
+        {"postbind4/",     BPF_PROG_TYPE_CGROUP_SOCK,      BPF_CGROUP_INET4_POST_BIND},
+        {"postbind6/",     BPF_PROG_TYPE_CGROUP_SOCK,      BPF_CGROUP_INET6_POST_BIND},
+        {"recvmsg4/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP4_RECVMSG},
+        {"recvmsg6/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_RECVMSG},
+        {"schedact/",      BPF_PROG_TYPE_SCHED_ACT,        BPF_ATTACH_TYPE_UNSPEC},
+        {"schedcls/",      BPF_PROG_TYPE_SCHED_CLS,        BPF_ATTACH_TYPE_UNSPEC},
+        {"sendmsg4/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP4_SENDMSG},
+        {"sendmsg6/",      BPF_PROG_TYPE_CGROUP_SOCK_ADDR, BPF_CGROUP_UDP6_SENDMSG},
+        {"setsockopt/",    BPF_PROG_TYPE_CGROUP_SOCKOPT,   BPF_CGROUP_SETSOCKOPT},
+        {"skfilter/",      BPF_PROG_TYPE_SOCKET_FILTER,    BPF_ATTACH_TYPE_UNSPEC},
+        {"sockops/",       BPF_PROG_TYPE_SOCK_OPS,         BPF_CGROUP_SOCK_OPS},
+        {"sysctl",         BPF_PROG_TYPE_CGROUP_SYSCTL,    BPF_CGROUP_SYSCTL},
+        {"tracepoint/",    BPF_PROG_TYPE_TRACEPOINT,       BPF_ATTACH_TYPE_UNSPEC},
+        {"uprobe/",        BPF_PROG_TYPE_KPROBE,           BPF_ATTACH_TYPE_UNSPEC},
+        {"uretprobe/",     BPF_PROG_TYPE_KPROBE,           BPF_ATTACH_TYPE_UNSPEC},
+        {"xdp/",           BPF_PROG_TYPE_XDP,              BPF_ATTACH_TYPE_UNSPEC},
+};
+
+typedef struct {
+    enum bpf_prog_type type;
+    enum bpf_attach_type expected_attach_type;
+    string name;
+    vector<char> data;
+    vector<char> rel_data;
+    optional<struct bpf_prog_def> prog_def;
+
+    unique_fd prog_fd; /* fd after loading */
+} codeSection;
+
+static int readElfHeader(ifstream& elfFile, Elf64_Ehdr* eh) {
+    elfFile.seekg(0);
+    if (elfFile.fail()) return -1;
+
+    if (!elfFile.read((char*)eh, sizeof(*eh))) return -1;
+
+    return 0;
+}
+
+/* Reads all section header tables into an Shdr array */
+static int readSectionHeadersAll(ifstream& elfFile, vector<Elf64_Shdr>& shTable) {
+    Elf64_Ehdr eh;
+    int ret = 0;
+
+    ret = readElfHeader(elfFile, &eh);
+    if (ret) return ret;
+
+    elfFile.seekg(eh.e_shoff);
+    if (elfFile.fail()) return -1;
+
+    /* Read shdr table entries */
+    shTable.resize(eh.e_shnum);
+
+    if (!elfFile.read((char*)shTable.data(), (eh.e_shnum * eh.e_shentsize))) return -ENOMEM;
+
+    return 0;
+}
+
+/* Read a section by its index - for ex to get sec hdr strtab blob */
+static int readSectionByIdx(ifstream& elfFile, int id, vector<char>& sec) {
+    vector<Elf64_Shdr> shTable;
+    int ret = readSectionHeadersAll(elfFile, shTable);
+    if (ret) return ret;
+
+    elfFile.seekg(shTable[id].sh_offset);
+    if (elfFile.fail()) return -1;
+
+    sec.resize(shTable[id].sh_size);
+    if (!elfFile.read(sec.data(), shTable[id].sh_size)) return -1;
+
+    return 0;
+}
+
+/* Read whole section header string table */
+static int readSectionHeaderStrtab(ifstream& elfFile, vector<char>& strtab) {
+    Elf64_Ehdr eh;
+    int ret = readElfHeader(elfFile, &eh);
+    if (ret) return ret;
+
+    ret = readSectionByIdx(elfFile, eh.e_shstrndx, strtab);
+    if (ret) return ret;
+
+    return 0;
+}
+
+/* Get name from offset in strtab */
+static int getSymName(ifstream& elfFile, int nameOff, string& name) {
+    int ret;
+    vector<char> secStrTab;
+
+    ret = readSectionHeaderStrtab(elfFile, secStrTab);
+    if (ret) return ret;
+
+    if (nameOff >= (int)secStrTab.size()) return -1;
+
+    name = string((char*)secStrTab.data() + nameOff);
+    return 0;
+}
+
+/* Reads a full section by name - example to get the GPL license */
+static int readSectionByName(const char* name, ifstream& elfFile, vector<char>& data) {
+    vector<char> secStrTab;
+    vector<Elf64_Shdr> shTable;
+    int ret;
+
+    ret = readSectionHeadersAll(elfFile, shTable);
+    if (ret) return ret;
+
+    ret = readSectionHeaderStrtab(elfFile, secStrTab);
+    if (ret) return ret;
+
+    for (int i = 0; i < (int)shTable.size(); i++) {
+        char* secname = secStrTab.data() + shTable[i].sh_name;
+        if (!secname) continue;
+
+        if (!strcmp(secname, name)) {
+            vector<char> dataTmp;
+            dataTmp.resize(shTable[i].sh_size);
+
+            elfFile.seekg(shTable[i].sh_offset);
+            if (elfFile.fail()) return -1;
+
+            if (!elfFile.read((char*)dataTmp.data(), shTable[i].sh_size)) return -1;
+
+            data = dataTmp;
+            return 0;
+        }
+    }
+    return -2;
+}
+
+unsigned int readSectionUint(const char* name, ifstream& elfFile, unsigned int defVal) {
+    vector<char> theBytes;
+    int ret = readSectionByName(name, elfFile, theBytes);
+    if (ret) {
+        ALOGD("Couldn't find section %s (defaulting to %u [0x%x]).", name, defVal, defVal);
+        return defVal;
+    } else if (theBytes.size() < sizeof(unsigned int)) {
+        ALOGE("Section %s too short (defaulting to %u [0x%x]).", name, defVal, defVal);
+        return defVal;
+    } else {
+        // decode first 4 bytes as LE32 uint, there will likely be more bytes due to alignment.
+        unsigned int value = static_cast<unsigned char>(theBytes[3]);
+        value <<= 8;
+        value += static_cast<unsigned char>(theBytes[2]);
+        value <<= 8;
+        value += static_cast<unsigned char>(theBytes[1]);
+        value <<= 8;
+        value += static_cast<unsigned char>(theBytes[0]);
+        ALOGI("Section %s value is %u [0x%x]", name, value, value);
+        return value;
+    }
+}
+
+static int readSectionByType(ifstream& elfFile, int type, vector<char>& data) {
+    int ret;
+    vector<Elf64_Shdr> shTable;
+
+    ret = readSectionHeadersAll(elfFile, shTable);
+    if (ret) return ret;
+
+    for (int i = 0; i < (int)shTable.size(); i++) {
+        if ((int)shTable[i].sh_type != type) continue;
+
+        vector<char> dataTmp;
+        dataTmp.resize(shTable[i].sh_size);
+
+        elfFile.seekg(shTable[i].sh_offset);
+        if (elfFile.fail()) return -1;
+
+        if (!elfFile.read((char*)dataTmp.data(), shTable[i].sh_size)) return -1;
+
+        data = dataTmp;
+        return 0;
+    }
+    return -2;
+}
+
+static bool symCompare(Elf64_Sym a, Elf64_Sym b) {
+    return (a.st_value < b.st_value);
+}
+
+static int readSymTab(ifstream& elfFile, int sort, vector<Elf64_Sym>& data) {
+    int ret, numElems;
+    Elf64_Sym* buf;
+    vector<char> secData;
+
+    ret = readSectionByType(elfFile, SHT_SYMTAB, secData);
+    if (ret) return ret;
+
+    buf = (Elf64_Sym*)secData.data();
+    numElems = (secData.size() / sizeof(Elf64_Sym));
+    data.assign(buf, buf + numElems);
+
+    if (sort) std::sort(data.begin(), data.end(), symCompare);
+    return 0;
+}
+
+static enum bpf_prog_type getFuseProgType() {
+    int result = BPF_PROG_TYPE_UNSPEC;
+    ifstream("/sys/fs/fuse/bpf_prog_type_fuse") >> result;
+    return static_cast<bpf_prog_type>(result);
+}
+
+static enum bpf_prog_type getSectionType(string& name) {
+    for (auto& snt : sectionNameTypes)
+        if (StartsWith(name, snt.name)) return snt.type;
+
+    // TODO Remove this code when fuse-bpf is upstream and this BPF_PROG_TYPE_FUSE is fixed
+    if (StartsWith(name, "fuse/")) return getFuseProgType();
+
+    return BPF_PROG_TYPE_UNSPEC;
+}
+
+static enum bpf_attach_type getExpectedAttachType(string& name) {
+    for (auto& snt : sectionNameTypes)
+        if (StartsWith(name, snt.name)) return snt.expected_attach_type;
+    return BPF_ATTACH_TYPE_UNSPEC;
+}
+
+static string getSectionName(enum bpf_prog_type type)
+{
+    for (auto& snt : sectionNameTypes)
+        if (snt.type == type)
+            return string(snt.name);
+
+    return "UNKNOWN SECTION NAME " + std::to_string(type);
+}
+
+static int readProgDefs(ifstream& elfFile, vector<struct bpf_prog_def>& pd,
+                        size_t sizeOfBpfProgDef) {
+    vector<char> pdData;
+    int ret = readSectionByName("progs", elfFile, pdData);
+    // Older file formats do not require a 'progs' section at all.
+    // (We should probably figure out whether this is behaviour which is safe to remove now.)
+    if (ret == -2) return 0;
+    if (ret) return ret;
+
+    if (pdData.size() % sizeOfBpfProgDef) {
+        ALOGE("readProgDefs failed due to improper sized progs section, %zu %% %zu != 0",
+              pdData.size(), sizeOfBpfProgDef);
+        return -1;
+    };
+
+    int progCount = pdData.size() / sizeOfBpfProgDef;
+    pd.resize(progCount);
+    size_t trimmedSize = std::min(sizeOfBpfProgDef, sizeof(struct bpf_prog_def));
+
+    const char* dataPtr = pdData.data();
+    for (auto& p : pd) {
+        // First we zero initialize
+        memset(&p, 0, sizeof(p));
+        // Then we set non-zero defaults
+        p.bpfloader_max_ver = DEFAULT_BPFLOADER_MAX_VER;  // v1.0
+        // Then we copy over the structure prefix from the ELF file.
+        memcpy(&p, dataPtr, trimmedSize);
+        // Move to next struct in the ELF file
+        dataPtr += sizeOfBpfProgDef;
+    }
+    return 0;
+}
+
+static int getSectionSymNames(ifstream& elfFile, const string& sectionName, vector<string>& names,
+                              optional<unsigned> symbolType = std::nullopt) {
+    int ret;
+    string name;
+    vector<Elf64_Sym> symtab;
+    vector<Elf64_Shdr> shTable;
+
+    ret = readSymTab(elfFile, 1 /* sort */, symtab);
+    if (ret) return ret;
+
+    /* Get index of section */
+    ret = readSectionHeadersAll(elfFile, shTable);
+    if (ret) return ret;
+
+    int sec_idx = -1;
+    for (int i = 0; i < (int)shTable.size(); i++) {
+        ret = getSymName(elfFile, shTable[i].sh_name, name);
+        if (ret) return ret;
+
+        if (!name.compare(sectionName)) {
+            sec_idx = i;
+            break;
+        }
+    }
+
+    /* No section found with matching name*/
+    if (sec_idx == -1) {
+        ALOGW("No %s section could be found in elf object", sectionName.c_str());
+        return -1;
+    }
+
+    for (int i = 0; i < (int)symtab.size(); i++) {
+        if (symbolType.has_value() && ELF_ST_TYPE(symtab[i].st_info) != symbolType) continue;
+
+        if (symtab[i].st_shndx == sec_idx) {
+            string s;
+            ret = getSymName(elfFile, symtab[i].st_name, s);
+            if (ret) return ret;
+            names.push_back(s);
+        }
+    }
+
+    return 0;
+}
+
+static bool IsAllowed(bpf_prog_type type, const bpf_prog_type* allowed, size_t numAllowed) {
+    if (allowed == nullptr) return true;
+
+    for (size_t i = 0; i < numAllowed; i++) {
+        if (allowed[i] == BPF_PROG_TYPE_UNSPEC) {
+            if (type == getFuseProgType()) return true;
+        } else if (type == allowed[i])
+            return true;
+    }
+
+    return false;
+}
+
+/* Read a section by its index - for ex to get sec hdr strtab blob */
+static int readCodeSections(ifstream& elfFile, vector<codeSection>& cs, size_t sizeOfBpfProgDef,
+                            const bpf_prog_type* allowed, size_t numAllowed) {
+    vector<Elf64_Shdr> shTable;
+    int entries, ret = 0;
+
+    ret = readSectionHeadersAll(elfFile, shTable);
+    if (ret) return ret;
+    entries = shTable.size();
+
+    vector<struct bpf_prog_def> pd;
+    ret = readProgDefs(elfFile, pd, sizeOfBpfProgDef);
+    if (ret) return ret;
+    vector<string> progDefNames;
+    ret = getSectionSymNames(elfFile, "progs", progDefNames);
+    if (!pd.empty() && ret) return ret;
+
+    for (int i = 0; i < entries; i++) {
+        string name;
+        codeSection cs_temp;
+        cs_temp.type = BPF_PROG_TYPE_UNSPEC;
+
+        ret = getSymName(elfFile, shTable[i].sh_name, name);
+        if (ret) return ret;
+
+        enum bpf_prog_type ptype = getSectionType(name);
+
+        if (ptype == BPF_PROG_TYPE_UNSPEC) continue;
+
+        if (!IsAllowed(ptype, allowed, numAllowed)) {
+            ALOGE("Program type %s not permitted here", getSectionName(ptype).c_str());
+            return -1;
+        }
+
+        // This must be done before '/' is replaced with '_'.
+        cs_temp.expected_attach_type = getExpectedAttachType(name);
+
+        string oldName = name;
+
+        // convert all slashes to underscores
+        std::replace(name.begin(), name.end(), '/', '_');
+
+        cs_temp.type = ptype;
+        cs_temp.name = name;
+
+        ret = readSectionByIdx(elfFile, i, cs_temp.data);
+        if (ret) return ret;
+        ALOGD("Loaded code section %d (%s)", i, name.c_str());
+
+        vector<string> csSymNames;
+        ret = getSectionSymNames(elfFile, oldName, csSymNames, STT_FUNC);
+        if (ret || !csSymNames.size()) return ret;
+        for (size_t i = 0; i < progDefNames.size(); ++i) {
+            if (!progDefNames[i].compare(csSymNames[0] + "_def")) {
+                cs_temp.prog_def = pd[i];
+                break;
+            }
+        }
+
+        /* Check for rel section */
+        if (cs_temp.data.size() > 0 && i < entries) {
+            ret = getSymName(elfFile, shTable[i + 1].sh_name, name);
+            if (ret) return ret;
+
+            if (name == (".rel" + oldName)) {
+                ret = readSectionByIdx(elfFile, i + 1, cs_temp.rel_data);
+                if (ret) return ret;
+                ALOGD("Loaded relo section %d (%s)", i, name.c_str());
+            }
+        }
+
+        if (cs_temp.data.size() > 0) {
+            cs.push_back(std::move(cs_temp));
+            ALOGD("Adding section %d to cs list", i);
+        }
+    }
+    return 0;
+}
+
+static int getSymNameByIdx(ifstream& elfFile, int index, string& name) {
+    vector<Elf64_Sym> symtab;
+    int ret = 0;
+
+    ret = readSymTab(elfFile, 0 /* !sort */, symtab);
+    if (ret) return ret;
+
+    if (index >= (int)symtab.size()) return -1;
+
+    return getSymName(elfFile, symtab[index].st_name, name);
+}
+
+static bool mapMatchesExpectations(const unique_fd& fd, const string& mapName,
+                                   const struct bpf_map_def& mapDef, const enum bpf_map_type type) {
+    // Assuming fd is a valid Bpf Map file descriptor then
+    // all the following should always succeed on a 4.14+ kernel.
+    // If they somehow do fail, they'll return -1 (and set errno),
+    // which should then cause (among others) a key_size mismatch.
+    int fd_type = bpfGetFdMapType(fd);
+    int fd_key_size = bpfGetFdKeySize(fd);
+    int fd_value_size = bpfGetFdValueSize(fd);
+    int fd_max_entries = bpfGetFdMaxEntries(fd);
+    int fd_map_flags = bpfGetFdMapFlags(fd);
+
+    // DEVMAPs are readonly from the bpf program side's point of view, as such
+    // the kernel in kernel/bpf/devmap.c dev_map_init_map() will set the flag
+    int desired_map_flags = (int)mapDef.map_flags;
+    if (type == BPF_MAP_TYPE_DEVMAP || type == BPF_MAP_TYPE_DEVMAP_HASH)
+        desired_map_flags |= BPF_F_RDONLY_PROG;
+
+    // The .h file enforces that this is a power of two, and page size will
+    // also always be a power of two, so this logic is actually enough to
+    // force it to be a multiple of the page size, as required by the kernel.
+    unsigned int desired_max_entries = mapDef.max_entries;
+    if (type == BPF_MAP_TYPE_RINGBUF) {
+        if (desired_max_entries < page_size) desired_max_entries = page_size;
+    }
+
+    // The following checks should *never* trigger, if one of them somehow does,
+    // it probably means a bpf .o file has been changed/replaced at runtime
+    // and bpfloader was manually rerun (normally it should only run *once*
+    // early during the boot process).
+    // Another possibility is that something is misconfigured in the code:
+    // most likely a shared map is declared twice differently.
+    // But such a change should never be checked into the source tree...
+    if ((fd_type == type) &&
+        (fd_key_size == (int)mapDef.key_size) &&
+        (fd_value_size == (int)mapDef.value_size) &&
+        (fd_max_entries == (int)desired_max_entries) &&
+        (fd_map_flags == desired_map_flags)) {
+        return true;
+    }
+
+    ALOGE("bpf map name %s mismatch: desired/found: "
+          "type:%d/%d key:%u/%d value:%u/%d entries:%u/%d flags:%u/%d",
+          mapName.c_str(), type, fd_type, mapDef.key_size, fd_key_size, mapDef.value_size,
+          fd_value_size, mapDef.max_entries, fd_max_entries, desired_map_flags, fd_map_flags);
+    return false;
+}
+
+static int createMaps(const char* elfPath, ifstream& elfFile, vector<unique_fd>& mapFds,
+                      const char* prefix, const unsigned long long allowedDomainBitmask,
+                      const size_t sizeOfBpfMapDef) {
+    int ret;
+    vector<char> mdData;
+    vector<struct bpf_map_def> md;
+    vector<string> mapNames;
+    string objName = pathToObjName(string(elfPath));
+
+    ret = readSectionByName("maps", elfFile, mdData);
+    if (ret == -2) return 0;  // no maps to read
+    if (ret) return ret;
+
+    if (mdData.size() % sizeOfBpfMapDef) {
+        ALOGE("createMaps failed due to improper sized maps section, %zu %% %zu != 0",
+              mdData.size(), sizeOfBpfMapDef);
+        return -1;
+    };
+
+    int mapCount = mdData.size() / sizeOfBpfMapDef;
+    md.resize(mapCount);
+    size_t trimmedSize = std::min(sizeOfBpfMapDef, sizeof(struct bpf_map_def));
+
+    const char* dataPtr = mdData.data();
+    for (auto& m : md) {
+        // First we zero initialize
+        memset(&m, 0, sizeof(m));
+        // Then we set non-zero defaults
+        m.bpfloader_max_ver = DEFAULT_BPFLOADER_MAX_VER;  // v1.0
+        m.max_kver = 0xFFFFFFFFu;                         // matches KVER_INF from bpf_helpers.h
+        // Then we copy over the structure prefix from the ELF file.
+        memcpy(&m, dataPtr, trimmedSize);
+        // Move to next struct in the ELF file
+        dataPtr += sizeOfBpfMapDef;
+    }
+
+    ret = getSectionSymNames(elfFile, "maps", mapNames);
+    if (ret) return ret;
+
+    unsigned kvers = kernelVersion();
+
+    for (int i = 0; i < (int)mapNames.size(); i++) {
+        if (md[i].zero != 0) abort();
+
+        if (BPFLOADER_VERSION < md[i].bpfloader_min_ver) {
+            ALOGI("skipping map %s which requires bpfloader min ver 0x%05x", mapNames[i].c_str(),
+                  md[i].bpfloader_min_ver);
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        if (BPFLOADER_VERSION >= md[i].bpfloader_max_ver) {
+            ALOGI("skipping map %s which requires bpfloader max ver 0x%05x", mapNames[i].c_str(),
+                  md[i].bpfloader_max_ver);
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        if (kvers < md[i].min_kver) {
+            ALOGI("skipping map %s which requires kernel version 0x%x >= 0x%x",
+                  mapNames[i].c_str(), kvers, md[i].min_kver);
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        if (kvers >= md[i].max_kver) {
+            ALOGI("skipping map %s which requires kernel version 0x%x < 0x%x",
+                  mapNames[i].c_str(), kvers, md[i].max_kver);
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        if ((md[i].ignore_on_eng && isEng()) || (md[i].ignore_on_user && isUser()) ||
+            (md[i].ignore_on_userdebug && isUserdebug())) {
+            ALOGI("skipping map %s which is ignored on %s builds", mapNames[i].c_str(),
+                  getBuildType().c_str());
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        if ((isArm() && isKernel32Bit() && md[i].ignore_on_arm32) ||
+            (isArm() && isKernel64Bit() && md[i].ignore_on_aarch64) ||
+            (isX86() && isKernel32Bit() && md[i].ignore_on_x86_32) ||
+            (isX86() && isKernel64Bit() && md[i].ignore_on_x86_64) ||
+            (isRiscV() && md[i].ignore_on_riscv64)) {
+            ALOGI("skipping map %s which is ignored on %s", mapNames[i].c_str(),
+                  describeArch());
+            mapFds.push_back(unique_fd());
+            continue;
+        }
+
+        enum bpf_map_type type = md[i].type;
+        if (type == BPF_MAP_TYPE_DEVMAP_HASH && !isAtLeastKernelVersion(5, 4, 0)) {
+            // On Linux Kernels older than 5.4 this map type doesn't exist, but it can kind
+            // of be approximated: HASH has the same userspace visible api.
+            // However it cannot be used by ebpf programs in the same way.
+            // Since bpf_redirect_map() only requires 4.14, a program using a DEVMAP_HASH map
+            // would fail to load (due to trying to redirect to a HASH instead of DEVMAP_HASH).
+            // One must thus tag any BPF_MAP_TYPE_DEVMAP_HASH + bpf_redirect_map() using
+            // programs as being 5.4+...
+            type = BPF_MAP_TYPE_HASH;
+        }
+
+        // The .h file enforces that this is a power of two, and page size will
+        // also always be a power of two, so this logic is actually enough to
+        // force it to be a multiple of the page size, as required by the kernel.
+        unsigned int max_entries = md[i].max_entries;
+        if (type == BPF_MAP_TYPE_RINGBUF) {
+            if (max_entries < page_size) max_entries = page_size;
+        }
+
+        domain selinux_context = getDomainFromSelinuxContext(md[i].selinux_context);
+        if (specified(selinux_context)) {
+            if (!inDomainBitmask(selinux_context, allowedDomainBitmask)) {
+                ALOGE("map %s has invalid selinux_context of %d (allowed bitmask 0x%llx)",
+                      mapNames[i].c_str(), selinux_context, allowedDomainBitmask);
+                return -EINVAL;
+            }
+            ALOGI("map %s selinux_context [%-32s] -> %d -> '%s' (%s)", mapNames[i].c_str(),
+                  md[i].selinux_context, selinux_context, lookupSelinuxContext(selinux_context),
+                  lookupPinSubdir(selinux_context));
+        }
+
+        domain pin_subdir = getDomainFromPinSubdir(md[i].pin_subdir);
+        if (unrecognized(pin_subdir)) return -ENOTDIR;
+        if (specified(pin_subdir)) {
+            if (!inDomainBitmask(pin_subdir, allowedDomainBitmask)) {
+                ALOGE("map %s has invalid pin_subdir of %d (allowed bitmask 0x%llx)",
+                      mapNames[i].c_str(), pin_subdir, allowedDomainBitmask);
+                return -EINVAL;
+            }
+            ALOGI("map %s pin_subdir [%-32s] -> %d -> '%s'", mapNames[i].c_str(), md[i].pin_subdir,
+                  pin_subdir, lookupPinSubdir(pin_subdir));
+        }
+
+        // Format of pin location is /sys/fs/bpf/<pin_subdir|prefix>map_<objName>_<mapName>
+        // except that maps shared across .o's have empty <objName>
+        // Note: <objName> refers to the extension-less basename of the .o file (without @ suffix).
+        string mapPinLoc = string(BPF_FS_PATH) + lookupPinSubdir(pin_subdir, prefix) + "map_" +
+                           (md[i].shared ? "" : objName) + "_" + mapNames[i];
+        bool reuse = false;
+        unique_fd fd;
+        int saved_errno;
+
+        if (access(mapPinLoc.c_str(), F_OK) == 0) {
+            fd.reset(mapRetrieveRO(mapPinLoc.c_str()));
+            saved_errno = errno;
+            ALOGD("bpf_create_map reusing map %s, ret: %d", mapNames[i].c_str(), fd.get());
+            reuse = true;
+        } else {
+            union bpf_attr req = {
+              .map_type = type,
+              .key_size = md[i].key_size,
+              .value_size = md[i].value_size,
+              .max_entries = max_entries,
+              .map_flags = md[i].map_flags,
+            };
+            strlcpy(req.map_name, mapNames[i].c_str(), sizeof(req.map_name));
+            fd.reset(bpf(BPF_MAP_CREATE, req));
+            saved_errno = errno;
+            ALOGD("bpf_create_map name %s, ret: %d", mapNames[i].c_str(), fd.get());
+        }
+
+        if (!fd.ok()) return -saved_errno;
+
+        // When reusing a pinned map, we need to check the map type/sizes/etc match, but for
+        // safety (since reuse code path is rare) run these checks even if we just created it.
+        // We assume failure is due to pinned map mismatch, hence the 'NOT UNIQUE' return code.
+        if (!mapMatchesExpectations(fd, mapNames[i], md[i], type)) return -ENOTUNIQ;
+
+        if (!reuse) {
+            if (specified(selinux_context)) {
+                string createLoc = string(BPF_FS_PATH) + lookupPinSubdir(selinux_context) +
+                                   "tmp_map_" + objName + "_" + mapNames[i];
+                ret = bpfFdPin(fd, createLoc.c_str());
+                if (ret) {
+                    int err = errno;
+                    ALOGE("create %s -> %d [%d:%s]", createLoc.c_str(), ret, err, strerror(err));
+                    return -err;
+                }
+                ret = renameat2(AT_FDCWD, createLoc.c_str(),
+                                AT_FDCWD, mapPinLoc.c_str(), RENAME_NOREPLACE);
+                if (ret) {
+                    int err = errno;
+                    ALOGE("rename %s %s -> %d [%d:%s]", createLoc.c_str(), mapPinLoc.c_str(), ret,
+                          err, strerror(err));
+                    return -err;
+                }
+            } else {
+                ret = bpfFdPin(fd, mapPinLoc.c_str());
+                if (ret) {
+                    int err = errno;
+                    ALOGE("pin %s -> %d [%d:%s]", mapPinLoc.c_str(), ret, err, strerror(err));
+                    return -err;
+                }
+            }
+            ret = chmod(mapPinLoc.c_str(), md[i].mode);
+            if (ret) {
+                int err = errno;
+                ALOGE("chmod(%s, 0%o) = %d [%d:%s]", mapPinLoc.c_str(), md[i].mode, ret, err,
+                      strerror(err));
+                return -err;
+            }
+            ret = chown(mapPinLoc.c_str(), (uid_t)md[i].uid, (gid_t)md[i].gid);
+            if (ret) {
+                int err = errno;
+                ALOGE("chown(%s, %u, %u) = %d [%d:%s]", mapPinLoc.c_str(), md[i].uid, md[i].gid,
+                      ret, err, strerror(err));
+                return -err;
+            }
+        }
+
+        int mapId = bpfGetFdMapId(fd);
+        if (mapId == -1) {
+            ALOGE("bpfGetFdMapId failed, ret: %d [%d]", mapId, errno);
+        } else {
+            ALOGI("map %s id %d", mapPinLoc.c_str(), mapId);
+        }
+
+        mapFds.push_back(std::move(fd));
+    }
+
+    return ret;
+}
+
+/* For debugging, dump all instructions */
+static void dumpIns(char* ins, int size) {
+    for (int row = 0; row < size / 8; row++) {
+        ALOGE("%d: ", row);
+        for (int j = 0; j < 8; j++) {
+            ALOGE("%3x ", ins[(row * 8) + j]);
+        }
+        ALOGE("\n");
+    }
+}
+
+/* For debugging, dump all code sections from cs list */
+static void dumpAllCs(vector<codeSection>& cs) {
+    for (int i = 0; i < (int)cs.size(); i++) {
+        ALOGE("Dumping cs %d, name %s", int(i), cs[i].name.c_str());
+        dumpIns((char*)cs[i].data.data(), cs[i].data.size());
+        ALOGE("-----------");
+    }
+}
+
+static void applyRelo(void* insnsPtr, Elf64_Addr offset, int fd) {
+    int insnIndex;
+    struct bpf_insn *insn, *insns;
+
+    insns = (struct bpf_insn*)(insnsPtr);
+
+    insnIndex = offset / sizeof(struct bpf_insn);
+    insn = &insns[insnIndex];
+
+    // Occasionally might be useful for relocation debugging, but pretty spammy
+    if (0) {
+        ALOGD("applying relo to instruction at byte offset: %llu, "
+              "insn offset %d, insn %llx",
+              (unsigned long long)offset, insnIndex, *(unsigned long long*)insn);
+    }
+
+    if (insn->code != (BPF_LD | BPF_IMM | BPF_DW)) {
+        ALOGE("Dumping all instructions till ins %d", insnIndex);
+        ALOGE("invalid relo for insn %d: code 0x%x", insnIndex, insn->code);
+        dumpIns((char*)insnsPtr, (insnIndex + 3) * 8);
+        return;
+    }
+
+    insn->imm = fd;
+    insn->src_reg = BPF_PSEUDO_MAP_FD;
+}
+
+static void applyMapRelo(ifstream& elfFile, vector<unique_fd> &mapFds, vector<codeSection>& cs) {
+    vector<string> mapNames;
+
+    int ret = getSectionSymNames(elfFile, "maps", mapNames);
+    if (ret) return;
+
+    for (int k = 0; k != (int)cs.size(); k++) {
+        Elf64_Rel* rel = (Elf64_Rel*)(cs[k].rel_data.data());
+        int n_rel = cs[k].rel_data.size() / sizeof(*rel);
+
+        for (int i = 0; i < n_rel; i++) {
+            int symIndex = ELF64_R_SYM(rel[i].r_info);
+            string symName;
+
+            ret = getSymNameByIdx(elfFile, symIndex, symName);
+            if (ret) return;
+
+            /* Find the map fd and apply relo */
+            for (int j = 0; j < (int)mapNames.size(); j++) {
+                if (!mapNames[j].compare(symName)) {
+                    applyRelo(cs[k].data.data(), rel[i].r_offset, mapFds[j]);
+                    break;
+                }
+            }
+        }
+    }
+}
+
+static int loadCodeSections(const char* elfPath, vector<codeSection>& cs, const string& license,
+                            const char* prefix, const unsigned long long allowedDomainBitmask) {
+    unsigned kvers = kernelVersion();
+
+    if (!kvers) {
+        ALOGE("unable to get kernel version");
+        return -EINVAL;
+    }
+
+    string objName = pathToObjName(string(elfPath));
+
+    for (int i = 0; i < (int)cs.size(); i++) {
+        unique_fd& fd = cs[i].prog_fd;
+        int ret;
+        string name = cs[i].name;
+
+        if (!cs[i].prog_def.has_value()) {
+            ALOGE("[%d] '%s' missing program definition! bad bpf.o build?", i, name.c_str());
+            return -EINVAL;
+        }
+
+        unsigned min_kver = cs[i].prog_def->min_kver;
+        unsigned max_kver = cs[i].prog_def->max_kver;
+        ALOGD("cs[%d].name:%s min_kver:%x .max_kver:%x (kvers:%x)", i, name.c_str(), min_kver,
+             max_kver, kvers);
+        if (kvers < min_kver) continue;
+        if (kvers >= max_kver) continue;
+
+        unsigned bpfMinVer = cs[i].prog_def->bpfloader_min_ver;
+        unsigned bpfMaxVer = cs[i].prog_def->bpfloader_max_ver;
+        domain selinux_context = getDomainFromSelinuxContext(cs[i].prog_def->selinux_context);
+        domain pin_subdir = getDomainFromPinSubdir(cs[i].prog_def->pin_subdir);
+        // Note: make sure to only check for unrecognized *after* verifying bpfloader
+        // version limits include this bpfloader's version.
+
+        ALOGD("cs[%d].name:%s requires bpfloader version [0x%05x,0x%05x)", i, name.c_str(),
+              bpfMinVer, bpfMaxVer);
+        if (BPFLOADER_VERSION < bpfMinVer) continue;
+        if (BPFLOADER_VERSION >= bpfMaxVer) continue;
+
+        if ((cs[i].prog_def->ignore_on_eng && isEng()) ||
+            (cs[i].prog_def->ignore_on_user && isUser()) ||
+            (cs[i].prog_def->ignore_on_userdebug && isUserdebug())) {
+            ALOGD("cs[%d].name:%s is ignored on %s builds", i, name.c_str(),
+                  getBuildType().c_str());
+            continue;
+        }
+
+        if ((isArm() && isKernel32Bit() && cs[i].prog_def->ignore_on_arm32) ||
+            (isArm() && isKernel64Bit() && cs[i].prog_def->ignore_on_aarch64) ||
+            (isX86() && isKernel32Bit() && cs[i].prog_def->ignore_on_x86_32) ||
+            (isX86() && isKernel64Bit() && cs[i].prog_def->ignore_on_x86_64) ||
+            (isRiscV() && cs[i].prog_def->ignore_on_riscv64)) {
+            ALOGD("cs[%d].name:%s is ignored on %s", i, name.c_str(), describeArch());
+            continue;
+        }
+
+        if (unrecognized(pin_subdir)) return -ENOTDIR;
+
+        if (specified(selinux_context)) {
+            if (!inDomainBitmask(selinux_context, allowedDomainBitmask)) {
+                ALOGE("prog %s has invalid selinux_context of %d (allowed bitmask 0x%llx)",
+                      name.c_str(), selinux_context, allowedDomainBitmask);
+                return -EINVAL;
+            }
+            ALOGI("prog %s selinux_context [%-32s] -> %d -> '%s' (%s)", name.c_str(),
+                  cs[i].prog_def->selinux_context, selinux_context,
+                  lookupSelinuxContext(selinux_context), lookupPinSubdir(selinux_context));
+        }
+
+        if (specified(pin_subdir)) {
+            if (!inDomainBitmask(pin_subdir, allowedDomainBitmask)) {
+                ALOGE("prog %s has invalid pin_subdir of %d (allowed bitmask 0x%llx)", name.c_str(),
+                      pin_subdir, allowedDomainBitmask);
+                return -EINVAL;
+            }
+            ALOGI("prog %s pin_subdir [%-32s] -> %d -> '%s'", name.c_str(),
+                  cs[i].prog_def->pin_subdir, pin_subdir, lookupPinSubdir(pin_subdir));
+        }
+
+        // strip any potential $foo suffix
+        // this can be used to provide duplicate programs
+        // conditionally loaded based on running kernel version
+        name = name.substr(0, name.find_last_of('$'));
+
+        bool reuse = false;
+        // Format of pin location is
+        // /sys/fs/bpf/<prefix>prog_<objName>_<progName>
+        string progPinLoc = string(BPF_FS_PATH) + lookupPinSubdir(pin_subdir, prefix) + "prog_" +
+                            objName + '_' + string(name);
+        if (access(progPinLoc.c_str(), F_OK) == 0) {
+            fd.reset(retrieveProgram(progPinLoc.c_str()));
+            ALOGD("New bpf prog load reusing prog %s, ret: %d (%s)", progPinLoc.c_str(), fd.get(),
+                  (!fd.ok() ? std::strerror(errno) : "no error"));
+            reuse = true;
+        } else {
+            vector<char> log_buf(BPF_LOAD_LOG_SZ, 0);
+
+            union bpf_attr req = {
+              .prog_type = cs[i].type,
+              .kern_version = kvers,
+              .license = ptr_to_u64(license.c_str()),
+              .insns = ptr_to_u64(cs[i].data.data()),
+              .insn_cnt = static_cast<__u32>(cs[i].data.size() / sizeof(struct bpf_insn)),
+              .log_level = 1,
+              .log_buf = ptr_to_u64(log_buf.data()),
+              .log_size = static_cast<__u32>(log_buf.size()),
+              .expected_attach_type = cs[i].expected_attach_type,
+            };
+            strlcpy(req.prog_name, cs[i].name.c_str(), sizeof(req.prog_name));
+            fd.reset(bpf(BPF_PROG_LOAD, req));
+
+            ALOGD("BPF_PROG_LOAD call for %s (%s) returned fd: %d (%s)", elfPath,
+                  cs[i].name.c_str(), fd.get(), (!fd.ok() ? std::strerror(errno) : "no error"));
+
+            if (!fd.ok()) {
+                vector<string> lines = android::base::Split(log_buf.data(), "\n");
+
+                ALOGW("BPF_PROG_LOAD - BEGIN log_buf contents:");
+                for (const auto& line : lines) ALOGW("%s", line.c_str());
+                ALOGW("BPF_PROG_LOAD - END log_buf contents.");
+
+                if (cs[i].prog_def->optional) {
+                    ALOGW("failed program is marked optional - continuing...");
+                    continue;
+                }
+                ALOGE("non-optional program failed to load.");
+            }
+        }
+
+        if (!fd.ok()) return fd.get();
+
+        if (!reuse) {
+            if (specified(selinux_context)) {
+                string createLoc = string(BPF_FS_PATH) + lookupPinSubdir(selinux_context) +
+                                   "tmp_prog_" + objName + '_' + string(name);
+                ret = bpfFdPin(fd, createLoc.c_str());
+                if (ret) {
+                    int err = errno;
+                    ALOGE("create %s -> %d [%d:%s]", createLoc.c_str(), ret, err, strerror(err));
+                    return -err;
+                }
+                ret = renameat2(AT_FDCWD, createLoc.c_str(),
+                                AT_FDCWD, progPinLoc.c_str(), RENAME_NOREPLACE);
+                if (ret) {
+                    int err = errno;
+                    ALOGE("rename %s %s -> %d [%d:%s]", createLoc.c_str(), progPinLoc.c_str(), ret,
+                          err, strerror(err));
+                    return -err;
+                }
+            } else {
+                ret = bpfFdPin(fd, progPinLoc.c_str());
+                if (ret) {
+                    int err = errno;
+                    ALOGE("create %s -> %d [%d:%s]", progPinLoc.c_str(), ret, err, strerror(err));
+                    return -err;
+                }
+            }
+            if (chmod(progPinLoc.c_str(), 0440)) {
+                int err = errno;
+                ALOGE("chmod %s 0440 -> [%d:%s]", progPinLoc.c_str(), err, strerror(err));
+                return -err;
+            }
+            if (chown(progPinLoc.c_str(), (uid_t)cs[i].prog_def->uid,
+                      (gid_t)cs[i].prog_def->gid)) {
+                int err = errno;
+                ALOGE("chown %s %d %d -> [%d:%s]", progPinLoc.c_str(), cs[i].prog_def->uid,
+                      cs[i].prog_def->gid, err, strerror(err));
+                return -err;
+            }
+        }
+
+        int progId = bpfGetFdProgId(fd);
+        if (progId == -1) {
+            ALOGE("bpfGetFdProgId failed, ret: %d [%d]", progId, errno);
+        } else {
+            ALOGI("prog %s id %d", progPinLoc.c_str(), progId);
+        }
+    }
+
+    return 0;
+}
+
+int loadProg(const char* elfPath, bool* isCritical, const Location& location) {
+    vector<char> license;
+    vector<char> critical;
+    vector<codeSection> cs;
+    vector<unique_fd> mapFds;
+    int ret;
+
+    if (!isCritical) return -1;
+    *isCritical = false;
+
+    ifstream elfFile(elfPath, ios::in | ios::binary);
+    if (!elfFile.is_open()) return -1;
+
+    ret = readSectionByName("critical", elfFile, critical);
+    *isCritical = !ret;
+
+    ret = readSectionByName("license", elfFile, license);
+    if (ret) {
+        ALOGE("Couldn't find license in %s", elfPath);
+        return ret;
+    } else {
+        ALOGD("Loading %s%s ELF object %s with license %s",
+              *isCritical ? "critical for " : "optional", *isCritical ? (char*)critical.data() : "",
+              elfPath, (char*)license.data());
+    }
+
+    // the following default values are for bpfloader V0.0 format which does not include them
+    unsigned int bpfLoaderMinVer =
+            readSectionUint("bpfloader_min_ver", elfFile, DEFAULT_BPFLOADER_MIN_VER);
+    unsigned int bpfLoaderMaxVer =
+            readSectionUint("bpfloader_max_ver", elfFile, DEFAULT_BPFLOADER_MAX_VER);
+    unsigned int bpfLoaderMinRequiredVer =
+            readSectionUint("bpfloader_min_required_ver", elfFile, 0);
+    size_t sizeOfBpfMapDef =
+            readSectionUint("size_of_bpf_map_def", elfFile, DEFAULT_SIZEOF_BPF_MAP_DEF);
+    size_t sizeOfBpfProgDef =
+            readSectionUint("size_of_bpf_prog_def", elfFile, DEFAULT_SIZEOF_BPF_PROG_DEF);
+
+    // inclusive lower bound check
+    if (BPFLOADER_VERSION < bpfLoaderMinVer) {
+        ALOGI("BpfLoader version 0x%05x ignoring ELF object %s with min ver 0x%05x",
+              BPFLOADER_VERSION, elfPath, bpfLoaderMinVer);
+        return 0;
+    }
+
+    // exclusive upper bound check
+    if (BPFLOADER_VERSION >= bpfLoaderMaxVer) {
+        ALOGI("BpfLoader version 0x%05x ignoring ELF object %s with max ver 0x%05x",
+              BPFLOADER_VERSION, elfPath, bpfLoaderMaxVer);
+        return 0;
+    }
+
+    if (BPFLOADER_VERSION < bpfLoaderMinRequiredVer) {
+        ALOGI("BpfLoader version 0x%05x failing due to ELF object %s with required min ver 0x%05x",
+              BPFLOADER_VERSION, elfPath, bpfLoaderMinRequiredVer);
+        return -1;
+    }
+
+    ALOGI("BpfLoader version 0x%05x processing ELF object %s with ver [0x%05x,0x%05x)",
+          BPFLOADER_VERSION, elfPath, bpfLoaderMinVer, bpfLoaderMaxVer);
+
+    if (sizeOfBpfMapDef < DEFAULT_SIZEOF_BPF_MAP_DEF) {
+        ALOGE("sizeof(bpf_map_def) of %zu is too small (< %d)", sizeOfBpfMapDef,
+              DEFAULT_SIZEOF_BPF_MAP_DEF);
+        return -1;
+    }
+
+    if (sizeOfBpfProgDef < DEFAULT_SIZEOF_BPF_PROG_DEF) {
+        ALOGE("sizeof(bpf_prog_def) of %zu is too small (< %d)", sizeOfBpfProgDef,
+              DEFAULT_SIZEOF_BPF_PROG_DEF);
+        return -1;
+    }
+
+    ret = readCodeSections(elfFile, cs, sizeOfBpfProgDef, location.allowedProgTypes,
+                           location.allowedProgTypesLength);
+    if (ret) {
+        ALOGE("Couldn't read all code sections in %s", elfPath);
+        return ret;
+    }
+
+    /* Just for future debugging */
+    if (0) dumpAllCs(cs);
+
+    ret = createMaps(elfPath, elfFile, mapFds, location.prefix, location.allowedDomainBitmask,
+                     sizeOfBpfMapDef);
+    if (ret) {
+        ALOGE("Failed to create maps: (ret=%d) in %s", ret, elfPath);
+        return ret;
+    }
+
+    for (int i = 0; i < (int)mapFds.size(); i++)
+        ALOGD("map_fd found at %d is %d in %s", i, mapFds[i].get(), elfPath);
+
+    applyMapRelo(elfFile, mapFds, cs);
+
+    ret = loadCodeSections(elfPath, cs, string(license.data()), location.prefix,
+                           location.allowedDomainBitmask);
+    if (ret) ALOGE("Failed to load programs, loadCodeSections ret=%d", ret);
+
+    return ret;
+}
+
+}  // namespace bpf
+}  // namespace android
diff --git a/netbpfload/loader.h b/netbpfload/loader.h
new file mode 100644
index 0000000..cc8a942
--- /dev/null
+++ b/netbpfload/loader.h
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ * Android BPF library - public API
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <linux/bpf.h>
+
+#include <fstream>
+
+namespace android {
+namespace bpf {
+
+// Bpf programs may specify per-program & per-map selinux_context and pin_subdir.
+//
+// The BpfLoader needs to convert these bpf.o specified strings into an enum
+// for internal use (to check that valid values were specified for the specific
+// location of the bpf.o file).
+//
+// It also needs to map selinux_context's into pin_subdir's.
+// This is because of how selinux_context is actually implemented via pin+rename.
+//
+// Thus 'domain' enumerates all selinux_context's/pin_subdir's that the BpfLoader
+// is aware of.  Thus there currently needs to be a 1:1 mapping between the two.
+//
+enum class domain : int {
+    unrecognized = -1,  // invalid for this version of the bpfloader
+    unspecified = 0,    // means just use the default for that specific pin location
+    platform,           //      fs_bpf               /sys/fs/bpf
+    tethering,          // (S+) fs_bpf_tethering     /sys/fs/bpf/tethering
+    net_private,        // (T+) fs_bpf_net_private   /sys/fs/bpf/net_private
+    net_shared,         // (T+) fs_bpf_net_shared    /sys/fs/bpf/net_shared
+    netd_readonly,      // (T+) fs_bpf_netd_readonly /sys/fs/bpf/netd_readonly
+    netd_shared,        // (T+) fs_bpf_netd_shared   /sys/fs/bpf/netd_shared
+    vendor,             // (T+) fs_bpf_vendor        /sys/fs/bpf/vendor
+    loader,             // (U+) fs_bpf_loader        /sys/fs/bpf/loader
+};
+
+// Note: this does not include domain::unrecognized, but does include domain::unspecified
+static constexpr domain AllDomains[] = {
+    domain::unspecified,
+    domain::platform,
+    domain::tethering,
+    domain::net_private,
+    domain::net_shared,
+    domain::netd_readonly,
+    domain::netd_shared,
+    domain::vendor,
+    domain::loader,
+};
+
+static constexpr bool unrecognized(domain d) {
+    return d == domain::unrecognized;
+}
+
+// Note: this doesn't handle unrecognized, handle it first.
+static constexpr bool specified(domain d) {
+    return d != domain::unspecified;
+}
+
+static constexpr unsigned long long domainToBitmask(domain d) {
+    return specified(d) ? 1uLL << (static_cast<int>(d) - 1) : 0;
+}
+
+static constexpr bool inDomainBitmask(domain d, unsigned long long v) {
+    return domainToBitmask(d) & v;
+}
+
+struct Location {
+    const char* const dir = "";
+    const char* const prefix = "";
+    unsigned long long allowedDomainBitmask = 0;
+    const bpf_prog_type* allowedProgTypes = nullptr;
+    size_t allowedProgTypesLength = 0;
+};
+
+// BPF loader implementation. Loads an eBPF ELF object
+int loadProg(const char* elfPath, bool* isCritical, const Location &location = {});
+
+// Exposed for testing
+unsigned int readSectionUint(const char* name, std::ifstream& elfFile, unsigned int defVal);
+
+// Returns the build type string (from ro.build.type).
+const std::string& getBuildType();
+
+// The following functions classify the 3 Android build types.
+inline bool isEng() {
+    return getBuildType() == "eng";
+}
+inline bool isUser() {
+    return getBuildType() == "user";
+}
+inline bool isUserdebug() {
+    return getBuildType() == "userdebug";
+}
+
+}  // namespace bpf
+}  // namespace android
diff --git a/netbpfload/netbpfload.rc b/netbpfload/netbpfload.rc
new file mode 100644
index 0000000..fd6eaea
--- /dev/null
+++ b/netbpfload/netbpfload.rc
@@ -0,0 +1,85 @@
+# zygote-start is what officially starts netd (see //system/core/rootdir/init.rc)
+# However, on some hardware it's started from post-fs-data as well, which is just
+# a tad earlier.  There's no benefit to that though, since on 4.9+ P+ devices netd
+# will just block until bpfloader finishes and sets the bpf.progs_loaded property.
+#
+# It is important that we start bpfloader after:
+#   - /sys/fs/bpf is already mounted,
+#   - apex (incl. rollback) is initialized (so that in the future we can load bpf
+#     programs shipped as part of apex mainline modules)
+#   - logd is ready for us to log stuff
+#
+# At the same time we want to be as early as possible to reduce races and thus
+# failures (before memory is fragmented, and cpu is busy running tons of other
+# stuff) and we absolutely want to be before netd and the system boot slot is
+# considered to have booted successfully.
+#
+on load_bpf_programs
+    exec_start bpfloader
+
+service bpfloader /system/bin/bpfloader
+    capabilities CHOWN SYS_ADMIN NET_ADMIN
+    # The following group memberships are a workaround for lack of DAC_OVERRIDE
+    # and allow us to open (among other things) files that we created and are
+    # no longer root owned (due to CHOWN) but still have group read access to
+    # one of the following groups.  This is not perfect, but a more correct
+    # solution requires significantly more effort to implement.
+    group root graphics network_stack net_admin net_bw_acct net_bw_stats net_raw system
+    user root
+    #
+    # Set RLIMIT_MEMLOCK to 1GiB for bpfloader
+    #
+    # Actually only 8MiB would be needed if bpfloader ran as its own uid.
+    #
+    # However, while the rlimit is per-thread, the accounting is system wide.
+    # So, for example, if the graphics stack has already allocated 10MiB of
+    # memlock data before bpfloader even gets a chance to run, it would fail
+    # if its memlock rlimit is only 8MiB - since there would be none left for it.
+    #
+    # bpfloader succeeding is critical to system health, since a failure will
+    # cause netd crashloop and thus system server crashloop... and the only
+    # recovery is a full kernel reboot.
+    #
+    # We've had issues where devices would sometimes (rarely) boot into
+    # a crashloop because bpfloader would occasionally lose a boot time
+    # race against the graphics stack's boot time locked memory allocation.
+    #
+    # Thus bpfloader's memlock has to be 8MB higher then the locked memory
+    # consumption of the root uid anywhere else in the system...
+    # But we don't know what that is for all possible devices...
+    #
+    # Ideally, we'd simply grant bpfloader the IPC_LOCK capability and it
+    # would simply ignore it's memlock rlimit... but it turns that this
+    # capability is not even checked by the kernel's bpf system call.
+    #
+    # As such we simply use 1GiB as a reasonable approximation of infinity.
+    #
+    rlimit memlock 1073741824 1073741824
+    oneshot
+    #
+    # How to debug bootloops caused by 'bpfloader-failed'.
+    #
+    # 1. On some lower RAM devices (like wembley) you may need to first enable developer mode
+    #    (from the Settings app UI), and change the developer option "Logger buffer sizes"
+    #    from the default (wembley: 64kB) to the maximum (1M) per log buffer.
+    #    Otherwise buffer will overflow before you manage to dump it and you'll get useless logs.
+    #
+    # 2. comment out 'reboot_on_failure reboot,bpfloader-failed' below
+    # 3. rebuild/reflash/reboot
+    # 4. as the device is booting up capture bpfloader logs via:
+    #    adb logcat -s 'bpfloader:*' 'LibBpfLoader:*'
+    #
+    # something like:
+    #   $ adb reboot; sleep 1; adb wait-for-device; adb root; sleep 1; adb wait-for-device; adb logcat -s 'bpfloader:*' 'LibBpfLoader:*'
+    # will take care of capturing logs as early as possible
+    #
+    # 5. look through the logs from the kernel's bpf verifier that bpfloader dumps out,
+    #    it usually makes sense to search back from the end and find the particular
+    #    bpf verifier failure that caused bpfloader to terminate early with an error code.
+    #    This will probably be something along the lines of 'too many jumps' or
+    #    'cannot prove return value is 0 or 1' or 'unsupported / unknown operation / helper',
+    #    'invalid bpf_context access', etc.
+    #
+    reboot_on_failure reboot,bpfloader-failed
+    # we're not really updatable, but want to be able to load bpf programs shipped in apexes
+    updatable
diff --git a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
index 5b75699..42f26f4 100644
--- a/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
+++ b/staticlibs/device/com/android/net/module/util/DeviceConfigUtils.java
@@ -64,6 +64,9 @@
     @VisibleForTesting
     public static final long DEFAULT_PACKAGE_VERSION = 1000;
 
+    private static final String CORE_NETWORKING_TRUNK_STABLE_NAMESPACE = "android_core_networking";
+    private static final String CORE_NETWORKING_TRUNK_STABLE_FLAG_PACKAGE = "com.android.net.flags";
+
     @VisibleForTesting
     public static void resetPackageVersionCacheForTest() {
         sPackageVersion = -1;
@@ -165,32 +168,18 @@
      *
      * This is useful to ensure that if a module install is rolled back, flags are not left fully
      * rolled out on a version where they have not been well tested.
+     *
+     * If the feature is disabled by default and enabled by flag push, this method should be used.
+     * If the feature is enabled by default and disabled by flag push (kill switch),
+     * {@link #isNetworkStackFeatureNotChickenedOut(Context, String)} should be used.
+     *
      * @param context The global context information about an app environment.
      * @param name The name of the property to look up.
      * @return true if this feature is enabled, or false if disabled.
      */
     public static boolean isNetworkStackFeatureEnabled(@NonNull Context context,
             @NonNull String name) {
-        return isNetworkStackFeatureEnabled(context, name, false /* defaultEnabled */);
-    }
-
-    /**
-     * Check whether or not one specific experimental feature for a particular namespace from
-     * {@link DeviceConfig} is enabled by comparing module package version
-     * with current version of property. If this property version is valid, the corresponding
-     * experimental feature would be enabled, otherwise disabled.
-     *
-     * This is useful to ensure that if a module install is rolled back, flags are not left fully
-     * rolled out on a version where they have not been well tested.
-     * @param context The global context information about an app environment.
-     * @param name The name of the property to look up.
-     * @param defaultEnabled The value to return if the property does not exist or its value is
-     *                       null.
-     * @return true if this feature is enabled, or false if disabled.
-     */
-    public static boolean isNetworkStackFeatureEnabled(@NonNull Context context,
-            @NonNull String name, boolean defaultEnabled) {
-        return isFeatureEnabled(NAMESPACE_CONNECTIVITY, name, defaultEnabled,
+        return isFeatureEnabled(NAMESPACE_CONNECTIVITY, name, false /* defaultEnabled */,
                 () -> getPackageVersion(context));
     }
 
@@ -420,4 +409,31 @@
 
         return pkgs.get(0).activityInfo.applicationInfo.packageName;
     }
+
+    /**
+     * Check whether one specific trunk stable flag in android_core_networking namespace is enabled.
+     * This method reads trunk stable feature flag value from DeviceConfig directly since
+     * java_aconfig_library soong module is not available in the mainline branch.
+     * After the mainline branch support the aconfig soong module, this function must be removed and
+     * java_aconfig_library must be used instead to check if the feature is enabled.
+     *
+     * @param flagName The name of the trunk stable flag
+     * @return true if this feature is enabled, or false if disabled.
+     */
+    public static boolean isTrunkStableFeatureEnabled(final String flagName) {
+        return isTrunkStableFeatureEnabled(
+                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
+                CORE_NETWORKING_TRUNK_STABLE_FLAG_PACKAGE,
+                flagName
+        );
+    }
+
+    private static boolean isTrunkStableFeatureEnabled(final String namespace,
+            final String packageName, final String flagName) {
+        return DeviceConfig.getBoolean(
+                namespace,
+                packageName + "." + flagName,
+                false /* defaultValue */
+        );
+    }
 }
diff --git a/staticlibs/native/bpf_headers/include/bpf/BpfClassic.h b/staticlibs/native/bpf_headers/include/bpf/BpfClassic.h
index dd0804c..f7ffddb 100644
--- a/staticlibs/native/bpf_headers/include/bpf/BpfClassic.h
+++ b/staticlibs/native/bpf_headers/include/bpf/BpfClassic.h
@@ -33,7 +33,7 @@
 	BPF_REJECT
 
 // *TWO* instructions: compare and if none of the bits are set jump over the reject statement
-#define BPF2_REJECT_IF_ANY_BITS_SET(v) \
+#define BPF2_REJECT_IF_ANY_MASKED_BITS_SET(v) \
 	BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, (v), 0, 1), \
 	BPF_REJECT
 
@@ -108,3 +108,55 @@
 	  _Static_assert(field_sizeof(struct ipv6hdr, field) == 4, "field of wrong size"); \
 	  offsetof(ipv6hdr, field); \
 	}))
+
+// Load the length of the IPv4 header into X index register.
+// ie. X := 4 * IPv4.IHL, where IPv4.IHL is the bottom nibble
+// of the first byte of the IPv4 (aka network layer) header.
+#define BPF_LOADX_NET_RELATIVE_IPV4_HLEN \
+    BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, (__u32)SKF_NET_OFF)
+
+// Blindly assumes no IPv6 extension headers, just does X := 40
+// You may later adjust this as you parse through IPv6 ext hdrs.
+#define BPF_LOADX_CONSTANT_IPV6_HLEN \
+    BPF_STMT(BPF_LDX | BPF_W | BPF_IMM, sizeof(struct ipv6hdr))
+
+// NOTE: all the following require X to be setup correctly (v4: 20+, v6: 40+)
+
+// 8-bit load from L4 (TCP/UDP/...) header
+#define BPF_LOAD_NETX_RELATIVE_L4_U8(ofs) \
+    BPF_STMT(BPF_LD | BPF_B | BPF_IND, (__u32)SKF_NET_OFF + (ofs))
+
+// Big/Network Endian 16-bit load from L4 (TCP/UDP/...) header
+#define BPF_LOAD_NETX_RELATIVE_L4_BE16(ofs) \
+    BPF_STMT(BPF_LD | BPF_H | BPF_IND, (__u32)SKF_NET_OFF + (ofs))
+
+// Big/Network Endian 32-bit load from L4 (TCP/UDP/...) header
+#define BPF_LOAD_NETX_RELATIVE_L4_BE32(ofs) \
+    BPF_STMT(BPF_LD | BPF_W | BPF_IND, (__u32)SKF_NET_OFF + (ofs))
+
+// Both ICMPv4 and ICMPv6 start with u8 type, u8 code
+#define BPF_LOAD_NETX_RELATIVE_ICMP_TYPE BPF_LOAD_NETX_RELATIVE_L4_U8(0)
+#define BPF_LOAD_NETX_RELATIVE_ICMP_CODE BPF_LOAD_NETX_RELATIVE_L4_U8(1)
+
+// IPv6 extension headers (HOPOPTS, DSTOPS, FRAG) begin with a u8 nexthdr
+#define BPF_LOAD_NETX_RELATIVE_V6EXTHDR_NEXTHDR BPF_LOAD_NETX_RELATIVE_L4_U8(0)
+
+// IPv6 fragment header is always exactly 8 bytes long
+#define BPF_LOAD_CONSTANT_V6FRAGHDR_LEN \
+    BPF_STMT(BPF_LD | BPF_IMM, 8)
+
+// HOPOPTS/DSTOPS follow up with 'u8 len', counting 8 byte units, (0->8, 1->16)
+// *THREE* instructions
+#define BPF3_LOAD_NETX_RELATIVE_V6EXTHDR_LEN \
+    BPF_LOAD_NETX_RELATIVE_L4_U8(1) \
+    BPF_STMT(BPF_ALU | BPF_ADD | BPF_K, 1) \
+    BPF_STMT(BPF_ALU | BPF_LSH | BPF_K, 3)
+
+// *TWO* instructions: A += X; X := A
+#define BPF2_ADD_A_TO_X \
+    BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0) \
+    BPF_STMT(BPF_MISC | BPF_TAX, 0)
+
+// UDP/UDPLITE/TCP/SCTP/DCCP all start with be16 srcport, dstport
+#define BPF_LOAD_NETX_RELATIVE_SRC_PORT BPF_LOAD_NETX_RELATIVE_L4_BE16(0)
+#define BPF_LOAD_NETX_RELATIVE_DST_PORT BPF_LOAD_NETX_RELATIVE_L4_BE16(2)
diff --git a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
index 9e04676..06b3e2f 100644
--- a/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
+++ b/staticlibs/tests/unit/src/com/android/net/module/util/DeviceConfigUtilsTest.java
@@ -71,6 +71,10 @@
 public class DeviceConfigUtilsTest {
     private static final String TEST_NAME_SPACE = "connectivity";
     private static final String TEST_EXPERIMENT_FLAG = "experiment_flag";
+    private static final String CORE_NETWORKING_TRUNK_STABLE_NAMESPACE = "android_core_networking";
+    private static final String TEST_TRUNK_STABLE_FLAG = "trunk_stable_feature";
+    private static final String TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY =
+            "com.android.net.flags.trunk_stable_feature";
     private static final int TEST_FLAG_VALUE = 28;
     private static final String TEST_FLAG_VALUE_STRING = "28";
     private static final int TEST_DEFAULT_FLAG_VALUE = 0;
@@ -301,15 +305,12 @@
         assertFalse(DeviceConfigUtils.isNetworkStackFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG));
         assertFalse(DeviceConfigUtils.isTetheringFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG));
 
-        // Follow defaultEnabled if the flag is not set
+        // If the flag is not set feature is disabled
         doReturn(null).when(() -> DeviceConfig.getProperty(NAMESPACE_CONNECTIVITY,
                 TEST_EXPERIMENT_FLAG));
         doReturn(null).when(() -> DeviceConfig.getProperty(NAMESPACE_TETHERING,
                 TEST_EXPERIMENT_FLAG));
-        assertFalse(DeviceConfigUtils.isNetworkStackFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG,
-                false /* defaultEnabled */));
-        assertTrue(DeviceConfigUtils.isNetworkStackFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG,
-                true /* defaultEnabled */));
+        assertFalse(DeviceConfigUtils.isNetworkStackFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG));
         assertFalse(DeviceConfigUtils.isTetheringFeatureEnabled(mContext, TEST_EXPERIMENT_FLAG));
     }
 
@@ -506,4 +507,25 @@
         verify(mContext, never()).getPackageName();
         verify(mPm, never()).getPackageInfo(anyString(), anyInt());
     }
+
+    @Test
+    public void testIsCoreNetworkingTrunkStableFeatureEnabled() {
+        doReturn(null).when(() -> DeviceConfig.getProperty(
+                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
+                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
+        assertFalse(DeviceConfigUtils.isTrunkStableFeatureEnabled(
+                TEST_TRUNK_STABLE_FLAG));
+
+        doReturn("false").when(() -> DeviceConfig.getProperty(
+                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
+                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
+        assertFalse(DeviceConfigUtils.isTrunkStableFeatureEnabled(
+                TEST_TRUNK_STABLE_FLAG));
+
+        doReturn("true").when(() -> DeviceConfig.getProperty(
+                CORE_NETWORKING_TRUNK_STABLE_NAMESPACE,
+                TEST_CORE_NETWORKING_TRUNK_STABLE_FLAG_PROPERTY));
+        assertTrue(DeviceConfigUtils.isTrunkStableFeatureEnabled(
+                TEST_TRUNK_STABLE_FLAG));
+    }
 }
diff --git a/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java b/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java
index 805dd65..ec5c8c5 100644
--- a/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java
+++ b/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java
@@ -22,6 +22,7 @@
 import static android.net.cts.util.CtsNetUtils.TestNetworkCallback;
 
 import static com.android.compatibility.common.util.SystemUtil.runWithShellPermissionIdentity;
+import static com.android.modules.utils.build.SdkLevel.isAtLeastU;
 import static com.android.modules.utils.build.SdkLevel.isAtLeastT;
 import static com.android.testutils.DevSdkIgnoreRuleKt.SC_V2;
 
@@ -60,11 +61,7 @@
 
 import com.android.internal.util.HexDump;
 import com.android.networkstack.apishim.ConstantsShim;
-import com.android.networkstack.apishim.Ikev2VpnProfileBuilderShimImpl;
-import com.android.networkstack.apishim.Ikev2VpnProfileShimImpl;
 import com.android.networkstack.apishim.VpnManagerShimImpl;
-import com.android.networkstack.apishim.common.Ikev2VpnProfileBuilderShim;
-import com.android.networkstack.apishim.common.Ikev2VpnProfileShim;
 import com.android.networkstack.apishim.common.VpnManagerShim;
 import com.android.networkstack.apishim.common.VpnProfileStateShim;
 import com.android.testutils.DevSdkIgnoreRule;
@@ -227,28 +224,25 @@
     }
 
     private Ikev2VpnProfile buildIkev2VpnProfileCommon(
-            @NonNull Ikev2VpnProfileBuilderShim builderShim, boolean isRestrictedToTestNetworks,
+            @NonNull Ikev2VpnProfile.Builder builder, boolean isRestrictedToTestNetworks,
             boolean requiresValidation, boolean automaticIpVersionSelectionEnabled,
             boolean automaticNattKeepaliveTimerEnabled) throws Exception {
 
-        builderShim.setBypassable(true)
+        builder.setBypassable(true)
                 .setAllowedAlgorithms(TEST_ALLOWED_ALGORITHMS)
                 .setProxy(TEST_PROXY_INFO)
                 .setMaxMtu(TEST_MTU)
                 .setMetered(false);
-        if (TestUtils.shouldTestTApis()) {
-            builderShim.setRequiresInternetValidation(requiresValidation);
+        if (isAtLeastT()) {
+            builder.setRequiresInternetValidation(requiresValidation);
         }
 
-        if (TestUtils.shouldTestUApis()) {
-            builderShim.setAutomaticIpVersionSelectionEnabled(automaticIpVersionSelectionEnabled);
-            builderShim.setAutomaticNattKeepaliveTimerEnabled(automaticNattKeepaliveTimerEnabled);
+        if (isAtLeastU()) {
+            builder.setAutomaticIpVersionSelectionEnabled(automaticIpVersionSelectionEnabled);
+            builder.setAutomaticNattKeepaliveTimerEnabled(automaticNattKeepaliveTimerEnabled);
         }
 
-        // Convert shim back to Ikev2VpnProfile.Builder since restrictToTestNetworks is a hidden
-        // method and is not defined in shims.
         // TODO: replace it in alternative way to remove the hidden method usage
-        final Ikev2VpnProfile.Builder builder = (Ikev2VpnProfile.Builder) builderShim.getBuilder();
         if (isRestrictedToTestNetworks) {
             builder.restrictToTestNetworks();
         }
@@ -264,16 +258,14 @@
                         ? IkeSessionTestUtils.IKE_PARAMS_V6 : IkeSessionTestUtils.IKE_PARAMS_V4,
                         IkeSessionTestUtils.CHILD_PARAMS);
 
-        final Ikev2VpnProfileBuilderShim builderShim =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(params)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(params)
                         .setRequiresInternetValidation(requiresValidation)
                         .setProxy(TEST_PROXY_INFO)
                         .setMaxMtu(TEST_MTU)
                         .setMetered(false);
-        // Convert shim back to Ikev2VpnProfile.Builder since restrictToTestNetworks is a hidden
-        // method and is not defined in shims.
+
         // TODO: replace it in alternative way to remove the hidden method usage
-        final Ikev2VpnProfile.Builder builder = (Ikev2VpnProfile.Builder) builderShim.getBuilder();
         if (isRestrictedToTestNetworks) {
             builder.restrictToTestNetworks();
         }
@@ -283,8 +275,8 @@
     private Ikev2VpnProfile buildIkev2VpnProfilePsk(@NonNull String remote,
             boolean isRestrictedToTestNetworks, boolean requiresValidation)
             throws Exception {
-        final Ikev2VpnProfileBuilderShim builder =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(remote, TEST_IDENTITY)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(remote, TEST_IDENTITY)
                         .setAuthPsk(TEST_PSK);
         return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks,
                 requiresValidation, false /* automaticIpVersionSelectionEnabled */,
@@ -293,8 +285,8 @@
 
     private Ikev2VpnProfile buildIkev2VpnProfileUsernamePassword(boolean isRestrictedToTestNetworks)
             throws Exception {
-        final Ikev2VpnProfileBuilderShim builder =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
                         .setAuthUsernamePassword(TEST_USER, TEST_PASSWORD, mServerRootCa);
         return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks,
                 false /* requiresValidation */, false /* automaticIpVersionSelectionEnabled */,
@@ -303,8 +295,8 @@
 
     private Ikev2VpnProfile buildIkev2VpnProfileDigitalSignature(boolean isRestrictedToTestNetworks)
             throws Exception {
-        final Ikev2VpnProfileBuilderShim builder =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
                         .setAuthDigitalSignature(
                                 mUserCertKey.cert, mUserCertKey.key, mServerRootCa);
         return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks,
@@ -347,7 +339,6 @@
     @Test
     public void testBuildIkev2VpnProfileWithIkeTunnelConnectionParams() throws Exception {
         assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
-        assumeTrue(TestUtils.shouldTestTApis());
 
         final IkeTunnelConnectionParams expectedParams = new IkeTunnelConnectionParams(
                 IkeSessionTestUtils.IKE_PARAMS_V6, IkeSessionTestUtils.CHILD_PARAMS);
@@ -567,7 +558,7 @@
         // regardless of its value. However, there is a race in Vpn(see b/228574221) that VPN may
         // misuse VPN network itself as the underlying network. The fix is not available without
         // SDK > T platform. Thus, verify this only on T+ platform.
-        if (!requiresValidation && TestUtils.shouldTestTApis()) {
+        if (!requiresValidation && isAtLeastT()) {
             cb.eventuallyExpect(CallbackEntry.NETWORK_CAPS_UPDATED, TIMEOUT_MS,
                     entry -> ((CallbackEntry.CapabilitiesChanged) entry).getCaps()
                             .hasCapability(NET_CAPABILITY_VALIDATED));
@@ -647,7 +638,6 @@
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileV4WithValidation() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(false /* testIpv6Only */, true /* requiresValidation */,
                 false /* testSessionKey */, false /* testIkeTunConnParams */);
     }
@@ -660,35 +650,30 @@
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileV6WithValidation() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(true /* testIpv6Only */, true /* requiresValidation */,
                 false /* testSessionKey */, false /* testIkeTunConnParams */);
     }
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileIkeTunConnParamsV4() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(false /* testIpv6Only */, false /* requiresValidation */,
                 false /* testSessionKey */, true /* testIkeTunConnParams */);
     }
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileIkeTunConnParamsV4WithValidation() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(false /* testIpv6Only */, true /* requiresValidation */,
                 false /* testSessionKey */, true /* testIkeTunConnParams */);
     }
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileIkeTunConnParamsV6() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(true /* testIpv6Only */, false /* requiresValidation */,
                 false /* testSessionKey */, true /* testIkeTunConnParams */);
     }
 
     @Test @IgnoreUpTo(SC_V2)
     public void testStartStopVpnProfileIkeTunConnParamsV6WithValidation() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(true /* testIpv6Only */, true /* requiresValidation */,
                 false /* testSessionKey */, true /* testIkeTunConnParams */);
     }
@@ -696,7 +681,6 @@
     @IgnoreUpTo(SC_V2)
     @Test
     public void testStartProvisionedVpnV4ProfileSession() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(false /* testIpv6Only */, false /* requiresValidation */,
                 true /* testSessionKey */, false /* testIkeTunConnParams */);
     }
@@ -704,59 +688,44 @@
     @IgnoreUpTo(SC_V2)
     @Test
     public void testStartProvisionedVpnV6ProfileSession() throws Exception {
-        assumeTrue(TestUtils.shouldTestTApis());
         doTestStartStopVpnProfile(true /* testIpv6Only */, false /* requiresValidation */,
                 true /* testSessionKey */, false /* testIkeTunConnParams */);
     }
 
+    @IgnoreUpTo(Build.VERSION_CODES.TIRAMISU)
     @Test
     public void testBuildIkev2VpnProfileWithAutomaticNattKeepaliveTimerEnabled() throws Exception {
-        // Cannot use @IgnoreUpTo(Build.VERSION_CODES.TIRAMISU) because this test also requires API
-        // 34 shims, and @IgnoreUpTo does not check that.
-        assumeTrue(TestUtils.shouldTestUApis());
-
         final Ikev2VpnProfile profileWithDefaultValue = buildIkev2VpnProfilePsk(TEST_SERVER_ADDR_V6,
                 false /* isRestrictedToTestNetworks */, false /* requiresValidation */);
-        final Ikev2VpnProfileShim<Ikev2VpnProfile> shimWithDefaultValue =
-                Ikev2VpnProfileShimImpl.newInstance(profileWithDefaultValue);
-        assertFalse(shimWithDefaultValue.isAutomaticNattKeepaliveTimerEnabled());
+        assertFalse(profileWithDefaultValue.isAutomaticNattKeepaliveTimerEnabled());
 
-        final Ikev2VpnProfileBuilderShim builder =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
                         .setAuthPsk(TEST_PSK);
         final Ikev2VpnProfile profile = buildIkev2VpnProfileCommon(builder,
                 false /* isRestrictedToTestNetworks */,
                 false /* requiresValidation */,
                 false /* automaticIpVersionSelectionEnabled */,
                 true /* automaticNattKeepaliveTimerEnabled */);
-        final Ikev2VpnProfileShim<Ikev2VpnProfile> shim =
-                Ikev2VpnProfileShimImpl.newInstance(profile);
-        assertTrue(shim.isAutomaticNattKeepaliveTimerEnabled());
+        assertTrue(profile.isAutomaticNattKeepaliveTimerEnabled());
     }
 
+    @IgnoreUpTo(Build.VERSION_CODES.TIRAMISU)
     @Test
     public void testBuildIkev2VpnProfileWithAutomaticIpVersionSelectionEnabled() throws Exception {
-        // Cannot use @IgnoreUpTo(Build.VERSION_CODES.TIRAMISU) because this test also requires API
-        // 34 shims, and @IgnoreUpTo does not check that.
-        assumeTrue(TestUtils.shouldTestUApis());
-
         final Ikev2VpnProfile profileWithDefaultValue = buildIkev2VpnProfilePsk(TEST_SERVER_ADDR_V6,
                 false /* isRestrictedToTestNetworks */, false /* requiresValidation */);
-        final Ikev2VpnProfileShim<Ikev2VpnProfile> shimWithDefaultValue =
-                Ikev2VpnProfileShimImpl.newInstance(profileWithDefaultValue);
-        assertFalse(shimWithDefaultValue.isAutomaticIpVersionSelectionEnabled());
+        assertFalse(profileWithDefaultValue.isAutomaticIpVersionSelectionEnabled());
 
-        final Ikev2VpnProfileBuilderShim builder =
-                Ikev2VpnProfileBuilderShimImpl.newInstance(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR_V6, TEST_IDENTITY)
                         .setAuthPsk(TEST_PSK);
         final Ikev2VpnProfile profile = buildIkev2VpnProfileCommon(builder,
                 false /* isRestrictedToTestNetworks */,
                 false /* requiresValidation */,
                 true /* automaticIpVersionSelectionEnabled */,
                 false /* automaticNattKeepaliveTimerEnabled */);
-        final Ikev2VpnProfileShim<Ikev2VpnProfile> shim =
-                Ikev2VpnProfileShimImpl.newInstance(profile);
-        assertTrue(shim.isAutomaticIpVersionSelectionEnabled());
+        assertTrue(profile.isAutomaticIpVersionSelectionEnabled());
     }
 
     private static class CertificateAndKey {