commit dece0d805fe0de736a410a11e4866d1150bed98e
author Chalard Jean <jchalard@google.com> Mon Nov 15 18:17:33 2021 +0900
committer Chalard Jean <jchalard@google.com> Mon Nov 15 21:18:25 2021 +0900
tree d2f43ff346a7d4f77fa10bd473cd3069d10b28c2
parent ff8169207713cb447d59df13aabf670b0f74ee5a

S- not to crash on NetworkInfo(null) or setDetailedState(null)

When NetworkInfo(null) or setDetailedState(null, any, any) are
called, S used to not crash but plant a null bomb for later
which may explode in some calls (notably, parceling) : see the
bug referenced below for details.

To help catching these errors earlier a patch was made to crash
as soon as one of these methods is called with a null argument,
but this will also crash incorrect use on existing code that
may never actually step on the mine, crashing code that used not
to crash. For safety, implement the new behavior only on T.

Bug: 145972387
Test: NetworkInfoTest
Change-Id: Ib710497d83b2d26439c2bd4d2f572310db97d6fd

framework/Android.bp

diff --git a/framework/Android.bp b/framework/Android.bp
index 5e7262a..d31f74f 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -80,6 +80,9 @@
         "framework-wifi.stubs.module_lib",
         "net-utils-device-common",
     ],
+    static_libs: [
+        "modules-utils-build",
+    ],
     libs: [
         "unsupportedappusage",
     ],

framework/jarjar-rules.txt

diff --git a/framework/jarjar-rules.txt b/framework/jarjar-rules.txt
index 2e5848c..ae6b9c3 100644
--- a/framework/jarjar-rules.txt
+++ b/framework/jarjar-rules.txt
@@ -1,2 +1,3 @@
 rule com.android.net.module.util.** android.net.connectivity.framework.util.@1
+rule com.android.modules.utils.** android.net.connectivity.framework.modules.utils.@1
 rule android.net.NetworkFactory* android.net.connectivity.framework.NetworkFactory@1

framework/src/android/net/NetworkInfo.java

diff --git a/framework/src/android/net/NetworkInfo.java b/framework/src/android/net/NetworkInfo.java
index 433933f..b7ec519 100644
--- a/framework/src/android/net/NetworkInfo.java
+++ b/framework/src/android/net/NetworkInfo.java
@@ -24,6 +24,7 @@
 import android.text.TextUtils;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.modules.utils.build.SdkLevel;
 
 import java.util.EnumMap;
 
@@ -180,6 +181,10 @@
     /** {@hide} */
     @UnsupportedAppUsage
     public NetworkInfo(@NonNull NetworkInfo source) {
+        // S- didn't use to crash when passing null. This plants a timebomb where mState and
+        // some other fields are null, but there may be existing code that relies on this behavior
+        // and doesn't trip the timebomb, so on SdkLevel < T, keep the old behavior. b/145972387
+        if (null == source && !SdkLevel.isAtLeastT()) return;
         synchronized (source) {
             mNetworkType = source.mNetworkType;
             mSubtype = source.mSubtype;
@@ -490,8 +495,9 @@
             this.mReason = reason;
             this.mExtraInfo = extraInfo;
             // Catch both the case where detailedState is null and the case where it's some
-            // unknown value
-            if (null == mState) {
+            // unknown value. This is clearly incorrect usage, but S- didn't use to crash (at
+            // least immediately) so keep the old behavior on older frameworks for safety.
+            if (null == mState && SdkLevel.isAtLeastT()) {
                 throw new NullPointerException("Unknown DetailedState : " + detailedState);
             }
         }