Paper/Spigot-Server-Patches/0054-Add-velocity-warnings.patch
Shane Freeder abba3d113b
Updated Upstream (Bukkit/CraftBukkit/Spigot)
Upstream has released updates that appears to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Bukkit Changes:
bb813f6f SPIGOT-4605: Warn against hacking physics

CraftBukkit Changes:
2ced0233 Don't handle sync packets for kicked players
d5e96882 SPIGOT-4602: Cache reflection in decompile error workaround

Spigot Changes:
b0f4c22b SPIGOT-4605: Catch more physics problems
2019-02-03 15:34:04 +00:00

96 lines
4.7 KiB
Diff

From dc6b34ee4cda4103a48869e9f2900c304aacf0f7 Mon Sep 17 00:00:00 2001
From: Joseph Hirschfeld <joe@ibj.io>
Date: Thu, 3 Mar 2016 02:48:12 -0600
Subject: [PATCH] Add velocity warnings
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index f4bce56ef..5dc92cb20 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -201,6 +201,7 @@ public final class CraftServer implements Server {
public boolean ignoreVanillaPermissions = false;
private final List<CraftPlayer> playerView;
public int reloadCount;
+ public static Exception excessiveVelEx; // Paper - Velocity warnings
private final class BooleanWrapper {
private boolean value = true;
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
index 9a5bb0222..a82717f5c 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
@@ -265,12 +265,44 @@ public abstract class CraftEntity implements org.bukkit.entity.Entity {
public void setVelocity(Vector velocity) {
Preconditions.checkArgument(velocity != null, "velocity");
velocity.checkFinite();
+
+ // Paper start - Warn server owners when plugins try to set super high velocities
+ if (!(this instanceof org.bukkit.entity.Projectile) && isUnsafeVelocity(velocity)) {
+ CraftServer.excessiveVelEx = new Exception("Excessive velocity set detected: tried to set velocity of entity " + entity.getName() + " id #" + getEntityId() + " to (" + velocity.getX() + "," + velocity.getY() + "," + velocity.getZ() + ").");
+ }
+ // Paper end
+
entity.motX = velocity.getX();
entity.motY = velocity.getY();
entity.motZ = velocity.getZ();
entity.velocityChanged = true;
}
+ // Paper start
+ /**
+ * Checks if the given velocity is not necessarily safe in all situations.
+ * This function returning true does not mean the velocity is dangerous or to be avoided, only that it may be
+ * a detriment to performance on the server.
+ *
+ * It is not to be used as a hard rule of any sort.
+ * Paper only uses it to warn server owners in watchdog crashes.
+ *
+ * @param vel incoming velocity to check
+ * @return if the velocity has the potential to be a performance detriment
+ */
+ private static boolean isUnsafeVelocity(Vector vel) {
+ final double x = vel.getX();
+ final double y = vel.getY();
+ final double z = vel.getZ();
+
+ if (x > 4 || x < -4 || y > 4 || y < -4 || z > 4 || z < -4) {
+ return true;
+ }
+
+ return false;
+ }
+ // Paper end
+
@Override
public double getHeight() {
return getHandle().length;
diff --git a/src/main/java/org/spigotmc/WatchdogThread.java b/src/main/java/org/spigotmc/WatchdogThread.java
index 8e32c4e2c..c080a6118 100644
--- a/src/main/java/org/spigotmc/WatchdogThread.java
+++ b/src/main/java/org/spigotmc/WatchdogThread.java
@@ -76,7 +76,19 @@ public class WatchdogThread extends Thread
log.log( Level.SEVERE, "During the run of the server, a physics stackoverflow was supressed" );
log.log( Level.SEVERE, "near " + net.minecraft.server.World.lastPhysicsProblem );
}
- //
+ // Paper start - Warn in watchdog if an excessive velocity was ever set
+ if ( org.bukkit.craftbukkit.CraftServer.excessiveVelEx != null )
+ {
+ log.log( Level.SEVERE, "------------------------------" );
+ log.log( Level.SEVERE, "During the run of the server, a plugin set an excessive velocity on an entity" );
+ log.log( Level.SEVERE, "This may be the cause of the issue, or it may be entirely unrelated" );
+ log.log( Level.SEVERE, org.bukkit.craftbukkit.CraftServer.excessiveVelEx.getMessage());
+ for ( StackTraceElement stack : org.bukkit.craftbukkit.CraftServer.excessiveVelEx.getStackTrace() )
+ {
+ log.log( Level.SEVERE, "\t\t" + stack );
+ }
+ }
+ // Paper end
log.log( Level.SEVERE, "------------------------------" );
log.log( Level.SEVERE, "Server thread dump (Look for plugins here before reporting to Paper!):" );
dumpThread( ManagementFactory.getThreadMXBean().getThreadInfo( MinecraftServer.getServer().primaryThread.getId(), Integer.MAX_VALUE ), log );
--
2.20.1