Fix FD leak in ConnectivityManager.getConnectionOwnerUid

Add unit tests to verify that bug has been fixed.

Re-enable testGetConnectionOwnerUid() unit tests in presubmit. These
were disabled due to test flakiness caused by expected failures passing
as a result of other sockets on the system. This is fixed by checking
that failures do not have the UID of the calling process instead of
INVALID_UID since previously some Qualcomm telephony sockets were
causing lookup successes.

Test: atest InetDiagSocketTest#testGetConnectionOwnerUid
Test: ls -1 /proc/<pid of system_server>/fd | wca
Test: atest --generate-new-metrics 200 InetDiagSocketTest#testGetConnectionOwnerUid
   To verify flakes have been cleaned up.
Bug: 141603906
Bug: 141459241
Change-Id: Ib76674f10e4bd24952c557bac7b9c65fba42fdb2

1 files changed, 16 insertions, 11 deletions

diff --git a/services/net/java/android/net/netlink/InetDiagMessage.java b/services/net/java/android/net/netlink/InetDiagMessage.java
index af9e601da9ec..31a2556f2041 100644
--- a/services/net/java/android/net/netlink/InetDiagMessage.java
+++ b/services/net/java/android/net/netlink/InetDiagMessage.java
@@ -16,26 +16,23 @@
 
 package android.net.netlink;
 
-import static android.os.Process.INVALID_UID;
 import static android.net.netlink.NetlinkConstants.SOCK_DIAG_BY_FAMILY;
 import static android.net.netlink.NetlinkSocket.DEFAULT_RECV_BUFSIZE;
 import static android.net.netlink.StructNlMsgHdr.NLM_F_DUMP;
 import static android.net.netlink.StructNlMsgHdr.NLM_F_REQUEST;
+import static android.os.Process.INVALID_UID;
 import static android.system.OsConstants.AF_INET;
 import static android.system.OsConstants.AF_INET6;
 import static android.system.OsConstants.IPPROTO_UDP;
 import static android.system.OsConstants.NETLINK_INET_DIAG;
 
-import android.os.Build;
-import android.os.Process;
+import android.net.util.SocketUtils;
 import android.system.ErrnoException;
 import android.util.Log;
 
 import java.io.FileDescriptor;
+import java.io.IOException;
 import java.io.InterruptedIOException;
-import java.net.DatagramSocket;
-import java.net.DatagramSocket;
-import java.net.InetAddress;
 import java.net.Inet4Address;
 import java.net.Inet6Address;
 import java.net.InetSocketAddress;
@@ -163,17 +160,25 @@ public class InetDiagMessage extends NetlinkMessage {
      */
     public static int getConnectionOwnerUid(int protocol, InetSocketAddress local,
                                             InetSocketAddress remote) {
+        int uid = INVALID_UID;
+        FileDescriptor fd = null;
         try {
-            final FileDescriptor fd = NetlinkSocket.forProto(NETLINK_INET_DIAG);
+            fd = NetlinkSocket.forProto(NETLINK_INET_DIAG);
             NetlinkSocket.connectToKernel(fd);
-
-            return lookupUid(protocol, local, remote, fd);
-
+            uid = lookupUid(protocol, local, remote, fd);
         } catch (ErrnoException | SocketException | IllegalArgumentException
                 | InterruptedIOException e) {
             Log.e(TAG, e.toString());
+        } finally {
+            if (fd != null) {
+                try {
+                    SocketUtils.closeSocket(fd);
+                } catch (IOException e) {
+                    Log.e(TAG, e.toString());
+                }
+            }
         }
-        return INVALID_UID;
+        return uid;
     }
 
     @Override