papermc/Spigot-Server-Patches/0053-Add-velocity-warnings.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

92 lines
4.7 KiB
Diff

From 347f8cdf5fb277a0f890d37684d941ab79d948fa 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 00b8fcb30..03e5d34be 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -230,6 +230,7 @@ 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
static {
ConfigurationSerialization.registerClass(CraftOfflinePlayer.class);
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
index d1d37c06b..ed496d03a 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
@@ -405,10 +405,41 @@ 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.setMot(CraftVector.toNMS(velocity));
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().getHeight();
diff --git a/src/main/java/org/spigotmc/WatchdogThread.java b/src/main/java/org/spigotmc/WatchdogThread.java
index 70b187190..56f5f54bd 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!):" ); // Paper
dumpThread( ManagementFactory.getThreadMXBean().getThreadInfo( MinecraftServer.getServer().serverThread.getId(), Integer.MAX_VALUE ), log );
--
2.21.0