From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Aikar Date: Thu, 3 Mar 2016 01:17:12 -0600 Subject: [PATCH] Ensure commands are not ran async Plugins calling Player.chat("/foo") or Server.dispatchCommand() could trigger the server to execute a command while on another thread. These commands would then process EXPECTING to be on the main thread, leaving to very hard to trace concurrency issues. This change will synchronize the command execution back to the main thread, causing a big slowdown in execution but throwing an exception at same time to raise awareness that it is happening so that plugin authors can fix their code to stop executing commands async. This also properly splits up the chat and command handling to reflect the server now having separate packets for both, and the client always using the correct packet. Text from a chat packet should never be parsed into a command, even if it starts with the `/` character. Co-authored-by: Jake Potrebic diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java index cdc24defe649644ceade1c6cfcfe20c29ca936c1..4fe65f979e8c3c15aea2211035745a71aef0feeb 100644 --- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java +++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java @@ -2026,7 +2026,7 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic return true; } - private static boolean isChatMessageIllegal(String message) { + public static boolean isChatMessageIllegal(String message) { // Paper - private -> public for (int i = 0; i < message.length(); ++i) { if (!SharedConstants.isAllowedChatCharacter(message.charAt(i))) { return true; @@ -2043,7 +2043,7 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic } OutgoingPlayerChatMessage outgoing = OutgoingPlayerChatMessage.create(original); - if (!async && s.startsWith("/")) { + if (false && !async && s.startsWith("/")) { // Paper - don't handle commands in chat logic this.handleCommand(s); } else if (this.player.getChatVisibility() == ChatVisiblity.SYSTEM) { // Do nothing, this is coming from a plugin @@ -2146,7 +2146,29 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Tic } } - private void handleCommand(String s) { + public void handleCommand(String s) { // Paper - private -> public + // Paper Start + if (!org.spigotmc.AsyncCatcher.shuttingDown && !org.bukkit.Bukkit.isPrimaryThread()) { + LOGGER.error("Command Dispatched Async: " + s); + LOGGER.error("Please notify author of plugin causing this execution to fix this bug! see: http://bit.ly/1oSiM6C", new Throwable()); + Waitable wait = new Waitable<>() { + @Override + protected Void evaluate() { + ServerGamePacketListenerImpl.this.handleCommand(s); + return null; + } + }; + server.processQueue.add(wait); + try { + wait.get(); + return; + } catch (InterruptedException e) { + Thread.currentThread().interrupt(); // This is proper habit for java. If we aren't handling it, pass it on! + } catch (Exception e) { + throw new RuntimeException("Exception processing chat command", e.getCause()); + } + } + // Paper End co.aikar.timings.MinecraftTimings.playerCommandTimer.startTiming(); // Paper if ( org.spigotmc.SpigotConfig.logCommands ) // Spigot this.LOGGER.info(this.player.getScoreboardName() + " issued server command: " + s); diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java index 56efe95512c851b965f2295d5eac7bc0c67bdb1f..1c6577bbbc005131661cbb4667cff6494b8fe5e4 100644 --- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java +++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java @@ -863,6 +863,28 @@ public final class CraftServer implements Server { Validate.notNull(commandLine, "CommandLine cannot be null"); org.spigotmc.AsyncCatcher.catchOp("command dispatch"); // Spigot + // Paper Start + if (!org.spigotmc.AsyncCatcher.shuttingDown && !Bukkit.isPrimaryThread()) { + final CommandSender fSender = sender; + final String fCommandLine = commandLine; + Bukkit.getLogger().log(Level.SEVERE, "Command Dispatched Async: " + commandLine); + Bukkit.getLogger().log(Level.SEVERE, "Please notify author of plugin causing this execution to fix this bug! see: http://bit.ly/1oSiM6C", new Throwable()); + org.bukkit.craftbukkit.util.Waitable wait = new org.bukkit.craftbukkit.util.Waitable() { + @Override + protected Boolean evaluate() { + return dispatchCommand(fSender, fCommandLine); + } + }; + net.minecraft.server.MinecraftServer.getServer().processQueue.add(wait); + try { + return wait.get(); + } catch (InterruptedException e) { + Thread.currentThread().interrupt(); // This is proper habit for java. If we aren't handling it, pass it on! + } catch (Exception e) { + throw new RuntimeException("Exception processing dispatch command", e.getCause()); + } + } + // Paper End if (this.commandMap.dispatch(sender, commandLine)) { return true; } diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java index 82a640887a75c360539c1787dbbb32750f6b1379..2666e55d72fd7731a2bde42d690762a2747dac90 100644 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java +++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java @@ -461,7 +461,19 @@ public class CraftPlayer extends CraftHumanEntity implements Player { public void chat(String msg) { if (this.getHandle().connection == null) return; - this.getHandle().connection.chat(msg, PlayerChatMessage.system(new ChatMessageContent(msg)), false); + // Paper start - improve chat handling + if (ServerGamePacketListenerImpl.isChatMessageIllegal(msg)) { + this.getHandle().connection.disconnect(Component.translatable("multiplayer.disconnect.illegal_characters"), org.bukkit.event.player.PlayerKickEvent.Cause.ILLEGAL_CHARACTERS); + } else { + if (msg.startsWith("/")) { + this.getHandle().connection.handleCommand(msg); + } else { + // TODO text filtering + // TODO chat decorating + this.getHandle().connection.chat(msg, PlayerChatMessage.system(new net.minecraft.network.chat.ChatMessageContent(msg)), false); + } + } + // Paper en } @Override diff --git a/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java b/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java index 19c44daaa407b7c1c7a7ffe56fef8c8814c6d5b2..6a073a9dc44d93eba296a0e18a9c7be8a7881725 100644 --- a/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java +++ b/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java @@ -13,6 +13,7 @@ public class ServerShutdownThread extends Thread { public void run() { try { org.spigotmc.AsyncCatcher.enabled = false; // Spigot + org.spigotmc.AsyncCatcher.shuttingDown = true; // Paper this.server.close(); } finally { try { diff --git a/src/main/java/org/spigotmc/AsyncCatcher.java b/src/main/java/org/spigotmc/AsyncCatcher.java index 78669fa035b7537ff7e533cf32aaf2995625424f..7585a30e8f063ac2656b5de519b1e9edaceffbc7 100644 --- a/src/main/java/org/spigotmc/AsyncCatcher.java +++ b/src/main/java/org/spigotmc/AsyncCatcher.java @@ -6,6 +6,7 @@ public class AsyncCatcher { public static boolean enabled = true; + public static boolean shuttingDown = false; // Paper public static void catchOp(String reason) { diff --git a/src/main/java/org/spigotmc/RestartCommand.java b/src/main/java/org/spigotmc/RestartCommand.java index 882e93ad4471e3688f2fcfb1e6f16926786ee5e7..94d8ba376cd1f024b244654cac9bb62bb19e3060 100644 --- a/src/main/java/org/spigotmc/RestartCommand.java +++ b/src/main/java/org/spigotmc/RestartCommand.java @@ -43,6 +43,7 @@ public class RestartCommand extends Command private static void restart(final String restartScript) { AsyncCatcher.enabled = false; // Disable async catcher incase it interferes with us + org.spigotmc.AsyncCatcher.shuttingDown = true; // Paper try { String[] split = restartScript.split( " " );