check netty4 channel open state before trying to set SO_LINGER

Author: original-brownbear

modules/transport-netty4/src/main/java/org/elasticsearch/transport/netty4/Netty4TcpChannel.java

@@ -72,7 +72,9 @@ public void addCloseListener(ActionListener<Void> listener) {
 
     @Override
     public void setSoLinger(int value) {
-        channel.config().setOption(ChannelOption.SO_LINGER, value);
+        if (channel.isOpen()) {
+            channel.config().setOption(ChannelOption.SO_LINGER, value);
+        }
     }
 
     @Override

server/src/main/java/org/elasticsearch/transport/TcpChannel.java

@@ -126,9 +126,8 @@ static void awaitConnected(DiscoveryNode discoveryNode, List<ActionFuture<Void>>
     static void rstAndClose(TcpChannel channel) {
         try {
             channel.setSoLinger(0);
-        } catch (IOException | RuntimeException e) {
-            // Depending on the implementation an already closed channel can either throw an IOException or a RuntimeException
-            // that we ignore because we are closing with RST because of an error here.
+        } catch (IOException e) {
+            // We ignore the exception as we are closing with RST because of an error.
         }
         CloseableChannel.closeChannel(channel);
     }