From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: xshu <xshu@google.com>
Date: Thu, 4 Nov 2021 16:51:09 +0800
Subject: [PATCH] Fix MAC address leak after SSR
Re-randomize MAC at interface up if the previous attempt to re-randomize
failed.
Bug: 197776883
Test: atest com.android.server.wifi
Change-Id: Ifffec40276171583f07868b81098bc7d17288ae1
CRs-Fixed: 3011538
(Cherry-picked from 85daf5384212f7892ca72a924e14298b2fade1c7)
---
.../android/server/wifi/ClientModeImpl.java | 34 ++++++++++++++++---
.../wifi/ConcreteClientModeManager.java | 3 ++
2 files changed, 32 insertions(+), 5 deletions(-)
diff --git a/service/java/com/android/server/wifi/ClientModeImpl.java b/service/java/com/android/server/wifi/ClientModeImpl.java
index cff2c0258..cacfeb874 100644
--- a/service/java/com/android/server/wifi/ClientModeImpl.java
+++ b/service/java/com/android/server/wifi/ClientModeImpl.java
@@ -249,6 +249,7 @@ public class ClientModeImpl extends StateMachine implements ClientMode {
private final String mInterfaceName;
private final ConcreteClientModeManager mClientModeManager;
+ private boolean mFailedToResetMacAddress = false;
private int mLastSignalLevel = -1;
private int mLastTxKbps = -1;
private int mLastRxKbps = -1;
@@ -1201,6 +1202,27 @@ public class ClientModeImpl extends StateMachine implements ClientMode {
return sb.toString();
}
+ /**
+ * receives changes in the interface up/down events for the interface associated with this
+ * ClientModeImpl. This is expected to be called from the ClientModeManager running on the
+ * wifi handler thread.
+ */
+ public void onUpChanged(boolean isUp) {
+ if (isUp && mFailedToResetMacAddress) {
+ // When the firmware does a subsystem restart, wifi will disconnect but we may fail to
+ // re-randomize the MAC address of the interface since it's undergoing recovery. Thus,
+ // check every time the interface goes up and re-randomize if the failure was detected.
+ if (mWifiGlobals.isConnectedMacRandomizationEnabled()) {
+ mFailedToResetMacAddress = !mWifiNative.setStaMacAddress(
+ mInterfaceName, MacAddressUtils.createRandomUnicastAddress());
+ if (mFailedToResetMacAddress) {
+ Log.e(getTag(), "Failed to set random MAC address on interface up");
+ }
+ }
+ }
+ // No need to handle interface down since it's already handled in the ClientModeManager.
+ }
+
public WifiLinkLayerStats getWifiLinkLayerStats() {
if (mInterfaceName == null) {
loge("getWifiLinkLayerStats called without an interface");
@@ -3205,9 +3227,10 @@ public class ClientModeImpl extends StateMachine implements ClientMode {
mLastSimBasedConnectionCarrierName = null;
mLastSignalLevel = -1;
if (mWifiGlobals.isConnectedMacRandomizationEnabled()) {
- if (!mWifiNative.setStaMacAddress(
- mInterfaceName, MacAddressUtils.createRandomUnicastAddress())) {
- Log.e(getTag(), "Failed to set random MAC address on bootup");
+ mFailedToResetMacAddress = !mWifiNative.setStaMacAddress(
+ mInterfaceName, MacAddressUtils.createRandomUnicastAddress());
+ if (mFailedToResetMacAddress) {
+ Log.e(getTag(), "Failed to set random MAC address on ClientMode creation");
}
}
mWifiInfo.setMacAddress(mWifiNative.getMacAddress(mInterfaceName));
@@ -4253,8 +4276,9 @@ public class ClientModeImpl extends StateMachine implements ClientMode {
// 2. Set a random MAC address to ensure that we're not leaking the MAC address.
mWifiNative.disableNetwork(mInterfaceName);
if (mWifiGlobals.isConnectedMacRandomizationEnabled()) {
- if (!mWifiNative.setStaMacAddress(
- mInterfaceName, MacAddressUtils.createRandomUnicastAddress())) {
+ mFailedToResetMacAddress = !mWifiNative.setStaMacAddress(
+ mInterfaceName, MacAddressUtils.createRandomUnicastAddress());
+ if (mFailedToResetMacAddress) {
Log.e(getTag(), "Failed to set random MAC address on disconnect");
}
}
diff --git a/service/java/com/android/server/wifi/ConcreteClientModeManager.java b/service/java/com/android/server/wifi/ConcreteClientModeManager.java
index 1e6d63d31..0c6183d58 100644
--- a/service/java/com/android/server/wifi/ConcreteClientModeManager.java
+++ b/service/java/com/android/server/wifi/ConcreteClientModeManager.java
@@ -856,6 +856,9 @@ public class ConcreteClientModeManager implements ClientModeManager {
Log.d(getTag(), "interface down!");
mStateMachine.sendMessage(CMD_INTERFACE_DOWN);
}
+ if (mClientModeImpl != null) {
+ mClientModeImpl.onUpChanged(isUp);
+ }
}
@Override