#3760: Fix possible NPE when trying to get encoder/decoder protocol

SpigotMC · Nov 17, 2024 · 7a42f12 · 7a42f12
1 parent 4886c4b
commit 7a42f12
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Showing 3 changed files with 81 additions and 34 deletions.
diff --git a/proxy/src/main/java/net/md_5/bungee/ServerConnection.java b/proxy/src/main/java/net/md_5/bungee/ServerConnection.java
@@ -5,7 +5,6 @@
 import java.net.SocketAddress;
 import java.util.ArrayDeque;
 import java.util.Queue;
-import java.util.concurrent.ConcurrentLinkedQueue;
 import lombok.Data;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
@@ -32,7 +31,7 @@ public class ServerConnection implements Server
     private final boolean forgeServer = false;
     @Getter
     private final Queue<KeepAliveData> keepAlives = new ArrayDeque<>();
-    private final Queue<DefinedPacket> packetQueue = new ConcurrentLinkedQueue<>();
+    private final Queue<DefinedPacket> packetQueue = new ArrayDeque<>();
 
     private final Unsafe unsafe = new Unsafe()
     {
@@ -45,23 +44,37 @@ public void sendPacket(DefinedPacket packet)
 
     public void sendPacketQueued(DefinedPacket packet)
     {
-        Protocol encodeProtocol = ch.getEncodeProtocol();
-        if ( !encodeProtocol.TO_SERVER.hasPacket( packet.getClass(), ch.getEncodeVersion() ) )
+        ch.scheduleIfNecessary( () ->
         {
-            packetQueue.add( packet );
-        } else
-        {
-            unsafe().sendPacket( packet );
-        }
+            if ( ch.isClosed() )
+            {
+                return;
+            }
+            Protocol encodeProtocol = ch.getEncodeProtocol();
+            if ( !encodeProtocol.TO_SERVER.hasPacket( packet.getClass(), ch.getEncodeVersion() ) )
+            {
+                packetQueue.add( packet );
+            } else
+            {
+                unsafe().sendPacket( packet );
+            }
+        } );
     }
 
     public void sendQueuedPackets()
     {
-        DefinedPacket packet;
-        while ( ( packet = packetQueue.poll() ) != null )
+        ch.scheduleIfNecessary( () ->
         {
-            unsafe().sendPacket( packet );
-        }
+            if ( ch.isClosed() )
+            {
+                return;
+            }
+            DefinedPacket packet;
+            while ( ( packet = packetQueue.poll() ) != null )
+            {
+                unsafe().sendPacket( packet );
+            }
+        } );
     }
 
     @Override

diff --git a/proxy/src/main/java/net/md_5/bungee/UserConnection.java b/proxy/src/main/java/net/md_5/bungee/UserConnection.java
@@ -11,6 +11,7 @@
 import io.netty.util.internal.PlatformDependent;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
+import java.util.ArrayDeque;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
@@ -21,7 +22,6 @@
 import java.util.Queue;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ConcurrentLinkedQueue;
 import java.util.logging.Level;
 import lombok.Getter;
 import lombok.NonNull;
@@ -146,7 +146,7 @@ public final class UserConnection implements ProxiedPlayer
     @Setter
     private ForgeServerHandler forgeServerHandler;
     /*========================================================================*/
-    private final Queue<DefinedPacket> packetQueue = new ConcurrentLinkedQueue<>();
+    private final Queue<DefinedPacket> packetQueue = new ArrayDeque<>();
     private final Unsafe unsafe = new Unsafe()
     {
         @Override
@@ -186,23 +186,37 @@ public void sendPacket(PacketWrapper packet)
 
     public void sendPacketQueued(DefinedPacket packet)
     {
-        Protocol encodeProtocol = ch.getEncodeProtocol();
-        if ( !encodeProtocol.TO_CLIENT.hasPacket( packet.getClass(), getPendingConnection().getVersion() ) )
+        ch.scheduleIfNecessary( () ->
         {
-            packetQueue.add( packet );
-        } else
-        {
-            unsafe().sendPacket( packet );
-        }
+            if ( ch.isClosed() )
+            {
+                return;
+            }
+            Protocol encodeProtocol = ch.getEncodeProtocol();
+            if ( !encodeProtocol.TO_CLIENT.hasPacket( packet.getClass(), getPendingConnection().getVersion() ) )
+            {
+                packetQueue.add( packet );
+            } else
+            {
+                unsafe().sendPacket( packet );
+            }
+        } );
     }
 
     public void sendQueuedPackets()
     {
-        DefinedPacket packet;
-        while ( ( packet = packetQueue.poll() ) != null )
+        ch.scheduleIfNecessary( () ->
         {
-            unsafe().sendPacket( packet );
-        }
+            if ( ch.isClosed() )
+            {
+                return;
+            }
+            DefinedPacket packet;
+            while ( ( packet = packetQueue.poll() ) != null )
+            {
+                unsafe().sendPacket( packet );
+            }
+        } );
     }
 
     @Deprecated

diff --git a/proxy/src/main/java/net/md_5/bungee/netty/ChannelWrapper.java b/proxy/src/main/java/net/md_5/bungee/netty/ChannelWrapper.java
@@ -42,23 +42,22 @@ public ChannelWrapper(ChannelHandlerContext ctx)
 
     public Protocol getDecodeProtocol()
     {
-        return ch.pipeline().get( MinecraftDecoder.class ).getProtocol();
+        return getMinecraftDecoder().getProtocol();
     }
 
     public void setDecodeProtocol(Protocol protocol)
     {
-        ch.pipeline().get( MinecraftDecoder.class ).setProtocol( protocol );
+        getMinecraftDecoder().setProtocol( protocol );
     }
 
     public Protocol getEncodeProtocol()
     {
-        return ch.pipeline().get( MinecraftEncoder.class ).getProtocol();
-
+        return getMinecraftEncoder().getProtocol();
     }
 
     public void setEncodeProtocol(Protocol protocol)
     {
-        ch.pipeline().get( MinecraftEncoder.class ).setProtocol( protocol );
+        getMinecraftEncoder().setProtocol( protocol );
     }
 
     public void setProtocol(Protocol protocol)
@@ -69,13 +68,23 @@ public void setProtocol(Protocol protocol)
 
     public void setVersion(int protocol)
     {
-        ch.pipeline().get( MinecraftDecoder.class ).setProtocolVersion( protocol );
-        ch.pipeline().get( MinecraftEncoder.class ).setProtocolVersion( protocol );
+        getMinecraftDecoder().setProtocolVersion( protocol );
+        getMinecraftEncoder().setProtocolVersion( protocol );
+    }
+
+    public MinecraftDecoder getMinecraftDecoder()
+    {
+        return ch.pipeline().get( MinecraftDecoder.class );
+    }
+
+    public MinecraftEncoder getMinecraftEncoder()
+    {
+        return ch.pipeline().get( MinecraftEncoder.class );
     }
 
     public int getEncodeVersion()
     {
-        return ch.pipeline().get( MinecraftEncoder.class ).getProtocolVersion();
+        return getMinecraftEncoder().getProtocolVersion();
     }
 
     public void write(Object packet)
@@ -223,4 +232,15 @@ public void updateComposite()
             packetCompressor.setCompose( compressorCompose );
         }
     }
+
+    public void scheduleIfNecessary(Runnable task)
+    {
+        if ( ch.eventLoop().inEventLoop() )
+        {
+            task.run();
+            return;
+        }
+
+        ch.eventLoop().execute( task );
+    }
 }