papermc/Spigot-Server-Patches/0044-Ensure-commands-are-not-ran-async.patch
Zach Brown 70ce6ce831
Move version command update checking to the implementation
This makes it easier for downstream projects (forks) to replace the
version fetching system with their own. It is as simple as implementing
an interface and overriding the default implementation of
org.bukkit.UnsafeValues#getVersionFetcher()

It also makes it easier for us to organize things like the version
history feature.

Lastly I have updated the paper implementation to check against the site
API rather than against jenkins.
2019-05-27 04:13:41 -05:00

122 lines
6.1 KiB
Diff

From 193308e8db069bec82d2856cce908670e58ea31a Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
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.
diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index a7104e966..f2e96da81 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -1578,6 +1578,29 @@ public class PlayerConnection implements PacketListenerPlayIn {
}
if (!async && s.startsWith("/")) {
+ // Paper Start
+ if (!org.spigotmc.AsyncCatcher.shuttingDown && !org.bukkit.Bukkit.isPrimaryThread()) {
+ final String fCommandLine = s;
+ MinecraftServer.LOGGER.log(org.apache.logging.log4j.Level.ERROR, "Command Dispatched Async: " + fCommandLine);
+ MinecraftServer.LOGGER.log(org.apache.logging.log4j.Level.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 Object evaluate() {
+ chat(fCommandLine, false);
+ return null;
+ }
+ };
+ minecraftServer.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
this.handleCommand(s);
} else if (this.player.getChatFlags() == EnumChatVisibility.SYSTEM) {
// Do nothing, this is coming from a plugin
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index d97cba9c0..a29b7b792 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -704,6 +704,29 @@ 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<Boolean> wait = new org.bukkit.craftbukkit.util.Waitable<Boolean>() {
+ @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 (commandMap.dispatch(sender, commandLine)) {
return true;
}
diff --git a/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java b/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java
index ddef523ea..70f8d4299 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
server.close();
} finally {
try {
diff --git a/src/main/java/org/spigotmc/AsyncCatcher.java b/src/main/java/org/spigotmc/AsyncCatcher.java
index aeed76972..9f7d2ef93 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 e7b953ca3..ccea803f5 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( " " );
--
2.21.0