Tell each VM to flush their DNS cache.

bug:3095357
Change-Id: I93de24e3e5a7d8b94d55f4facfffc863a2b8c202

2 files changed, 25 insertions, 0 deletions

diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index ee0cc4b..c18262e 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -1596,6 +1596,12 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             } catch (NumberFormatException e) {}
         }
         SystemProperties.set("net.dnschange", "" + (n+1));
+        /*
+         * Tell the VMs to toss their DNS caches
+         */
+        Intent intent = new Intent(Intent.ACTION_CLEAR_DNS_CACHE);
+        intent.addFlags(Intent.FLAG_RECEIVER_REPLACE_PENDING);
+        mContext.sendBroadcast(intent);
     }
 
     private void handleDnsConfigurationChange(int netType) {
diff --git a/services/java/com/android/server/am/ActivityManagerService.java b/services/java/com/android/server/am/ActivityManagerService.java
index 60b2b67..7905dc6 100644
--- a/services/java/com/android/server/am/ActivityManagerService.java
+++ b/services/java/com/android/server/am/ActivityManagerService.java
@@ -959,6 +959,7 @@ public final class ActivityManagerService extends ActivityManagerNative
     static final int CANCEL_HEAVY_NOTIFICATION_MSG = 25;
     static final int SHOW_STRICT_MODE_VIOLATION_MSG = 26;
     static final int CHECK_EXCESSIVE_WAKE_LOCKS_MSG = 27;
+    static final int CLEAR_DNS_CACHE = 28;
 
     AlertDialog mUidAlert;
 
@@ -1110,6 +1111,20 @@ public final class ActivityManagerService extends ActivityManagerNative
                     }
                 }
             } break;
+            case CLEAR_DNS_CACHE: {
+                synchronized (ActivityManagerService.this) {
+                    for (int i = mLruProcesses.size() - 1 ; i >= 0 ; i--) {
+                        ProcessRecord r = mLruProcesses.get(i);
+                        if (r.thread != null) {
+                            try {
+                                r.thread.clearDnsCache();
+                            } catch (RemoteException ex) {
+                                Slog.w(TAG, "Failed to clear dns cache for: " + r.info.processName);
+                            }
+                        }
+                    }
+                }
+            } break;
             case SHOW_UID_ERROR_MSG: {
                 // XXX This is a temporary dialog, no need to localize.
                 AlertDialog d = new BaseErrorDialog(mContext);
@@ -10373,6 +10388,10 @@ public final class ActivityManagerService extends ActivityManagerNative
             mHandler.sendEmptyMessage(UPDATE_TIME_ZONE);
         }
 
+        if (intent.ACTION_CLEAR_DNS_CACHE.equals(intent.getAction())) {
+            mHandler.sendEmptyMessage(CLEAR_DNS_CACHE);
+        }
+
         /*
          * Prevent non-system code (defined here to be non-persistent
          * processes) from sending protected broadcasts.