Avoid netlink socket address conflict

NetlinkManager previously bound all netlink sockets with nl_pid =
getpid(). Unfortunately only the first such socket is allowed to claim
nl_pid = getpid(). The kernel is happy to assign this value
automatically if nl_pid = 0. For more information on nl_pid see "man 7
netlink".

When NFLogListener was added, it created a socket with a kernel assigned
nl_pid, unfortunately the kernel assigns getpid() to the first such
socket and listener was initialized earlier in the startup process than
NetlinkManager.

This change alters NetlinkManager to request a kernel assigned nl_pid and
defensively moves the initialization of NFLogListener later in the
startup sequence to favor proper operation of existing code in
NetlinkManager. Error logging is also slightly improved.

Test: as follows
    - built
    - flashed
    - booted
    - "runtest -x .../netd_unit_test.cpp" passes
    - "cts-tradefed run commandAndExit cts-dev -m CtsOsTestCases -t
       android.os.cts.StrictModeTest" passes
Bug: 62353125

Change-Id: I9c1c76e5769de75ff624bf43634ac4061c447a72

1 files changed, 15 insertions, 11 deletions

diff --git a/server/main.cpp b/server/main.cpp
index 50570fd3..27596f7d 100644
--- a/server/main.cpp
+++ b/server/main.cpp
@@ -83,19 +83,8 @@ int main() {
         exit(1);
     };
 
-    std::unique_ptr<NFLogListener> logListener;
-    {
-        auto result = makeNFLogListener();
-        if (!isOk(result)) {
-            ALOGE("Unable to create NFLogListener: %s", result.status().msg().c_str());
-            exit(1);
-        }
-        logListener = std::move(result.value());
-    }
-
     gCtls = new android::net::Controllers();
     gCtls->init();
-    gCtls->wakeupCtrl.init(logListener.get());
 
     CommandListener cl;
     nm->setBroadcaster((SocketListener *) &cl);
@@ -105,6 +94,21 @@ int main() {
         exit(1);
     }
 
+    std::unique_ptr<NFLogListener> logListener;
+    {
+        auto result = makeNFLogListener();
+        if (!isOk(result)) {
+            ALOGE("Unable to create NFLogListener: %s", toString(result).c_str());
+            exit(1);
+        }
+        logListener = std::move(result.value());
+        auto status = gCtls->wakeupCtrl.init(logListener.get());
+        if (!isOk(result)) {
+            ALOGE("Unable to init WakeupController: %s", toString(result).c_str());
+            // We can still continue without wakeup packet logging.
+        }
+    }
+
     // Set local DNS mode, to prevent bionic from proxying
     // back to this service, recursively.
     setenv("ANDROID_DNS_MODE", "local", 1);