Paper/patches/server/0413-Fix-for-large-move-vectors-crashing-server.patch
Spottedleaf 8c5b837e05 Rework async chunk api implementation
Firstly, the old methods all routed to the CompletableFuture method.
However, the CF method could not guarantee that if the caller
was off-main that the future would be "completed" on-main. Since
the callback methods used the CF one, this meant that the callback
methods did not guarantee that the callbacks were to be called on
the main thread.

Now, all methods route to getChunkAtAsync(x, z, gen, urgent, cb)
so that the methods with the callback are guaranteed to invoke
the callback on the main thread. The CF behavior remains unchanged;
it may still appear to complete on main if invoked off-main.

Secondly, remove the scheduleOnMain invocation in the async
chunk completion. This unnecessarily delays the callback
by 1 tick.

Thirdly, add getChunksAtAsync(minX, minZ, maxX, maxZ, ...) which
will load chunks within an area. This method is provided as a helper
as keeping all chunks loaded within an area can be complicated to
implement for plugins (due to the lacking ticket API), and is
already implemented internally anyways.

Fourthly, remove the ticket addition that occured with getChunkAt
and getChunkAtAsync. The ticket addition may delay the unloading
of the chunk unnecessarily. It also fixes a very rare timing bug
where the future/callback would be completed after the chunk
unloads.
2024-11-18 23:00:59 -08:00

87 lines
6.0 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sun, 17 May 2020 23:47:33 -0700
Subject: [PATCH] Fix for large move vectors crashing server
Check movement distance also based on current position.
diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
index 1754e413dc1b7a18b3fc0b981eae11283b2106e5..fc06281b6d37d72a0a333343fc800bd388713a5f 100644
--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
@@ -497,9 +497,9 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
float prevYaw = this.player.getYRot();
float prevPitch = this.player.getXRot();
// CraftBukkit end
- double d0 = entity.getX();
- double d1 = entity.getY();
- double d2 = entity.getZ();
+ double d0 = entity.getX();final double fromX = d0; // Paper - OBFHELPER
+ double d1 = entity.getY();final double fromY = d1; // Paper - OBFHELPER
+ double d2 = entity.getZ();final double fromZ = d2; // Paper - OBFHELPER
double d3 = ServerGamePacketListenerImpl.clampHorizontal(packet.getX()); final double toX = d3; // Paper - OBFHELPER
double d4 = ServerGamePacketListenerImpl.clampVertical(packet.getY()); final double toY = d4; // Paper - OBFHELPER
double d5 = ServerGamePacketListenerImpl.clampHorizontal(packet.getZ()); final double toZ = d5; // Paper - OBFHELPER
@@ -509,7 +509,16 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
double d7 = d4 - this.vehicleFirstGoodY;
double d8 = d5 - this.vehicleFirstGoodZ;
double d9 = entity.getDeltaMovement().lengthSqr();
- double d10 = d6 * d6 + d7 * d7 + d8 * d8;
+ // Paper start - fix large move vectors killing the server
+ double currDeltaX = toX - fromX;
+ double currDeltaY = toY - fromY;
+ double currDeltaZ = toZ - fromZ;
+ double d10 = Math.max(d6 * d6 + d7 * d7 + d8 * d8, (currDeltaX * currDeltaX + currDeltaY * currDeltaY + currDeltaZ * currDeltaZ) - 1);
+ double otherFieldX = d3 - this.vehicleLastGoodX;
+ double otherFieldY = d4 - this.vehicleLastGoodY - 1.0E-6D;
+ double otherFieldZ = d5 - this.vehicleLastGoodZ;
+ d10 = Math.max(d10, (otherFieldX * otherFieldX + otherFieldY * otherFieldY + otherFieldZ * otherFieldZ) - 1);
+ // Paper end - fix large move vectors killing the server
// CraftBukkit start - handle custom speeds and skipped ticks
this.allowedPlayerTicks += (System.currentTimeMillis() / 50) - this.lastTick;
@@ -555,9 +564,9 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
boolean flag = worldserver.noCollision(entity, entity.getBoundingBox().deflate(0.0625D));
- d6 = d3 - this.vehicleLastGoodX;
- d7 = d4 - this.vehicleLastGoodY - 1.0E-6D;
- d8 = d5 - this.vehicleLastGoodZ;
+ d6 = d3 - this.vehicleLastGoodX; // Paper - diff on change, used for checking large move vectors above
+ d7 = d4 - this.vehicleLastGoodY - 1.0E-6D; // Paper - diff on change, used for checking large move vectors above
+ d8 = d5 - this.vehicleLastGoodZ; // Paper - diff on change, used for checking large move vectors above
boolean flag1 = entity.verticalCollisionBelow;
if (entity instanceof LivingEntity) {
@@ -1264,7 +1273,16 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
double d7 = d1 - this.firstGoodY;
double d8 = d2 - this.firstGoodZ;
double d9 = this.player.getDeltaMovement().lengthSqr();
- double d10 = d6 * d6 + d7 * d7 + d8 * d8;
+ // Paper start - fix large move vectors killing the server
+ double currDeltaX = toX - prevX;
+ double currDeltaY = toY - prevY;
+ double currDeltaZ = toZ - prevZ;
+ double d10 = Math.max(d6 * d6 + d7 * d7 + d8 * d8, (currDeltaX * currDeltaX + currDeltaY * currDeltaY + currDeltaZ * currDeltaZ) - 1);
+ double otherFieldX = d0 - this.lastGoodX;
+ double otherFieldY = d1 - this.lastGoodY;
+ double otherFieldZ = d2 - this.lastGoodZ;
+ d10 = Math.max(d10, (otherFieldX * otherFieldX + otherFieldY * otherFieldY + otherFieldZ * otherFieldZ) - 1);
+ // Paper end - fix large move vectors killing the server
if (this.player.isSleeping()) {
if (d10 > 1.0D) {
@@ -1320,9 +1338,9 @@ public class ServerGamePacketListenerImpl extends ServerCommonPacketListenerImpl
AABB axisalignedbb = this.player.getBoundingBox();
- d6 = d0 - this.lastGoodX;
- d7 = d1 - this.lastGoodY;
- d8 = d2 - this.lastGoodZ;
+ d6 = d0 - this.lastGoodX; // Paper - diff on change, used for checking large move vectors above
+ d7 = d1 - this.lastGoodY; // Paper - diff on change, used for checking large move vectors above
+ d8 = d2 - this.lastGoodZ; // Paper - diff on change, used for checking large move vectors above
boolean flag1 = d7 > 0.0D;
if (this.player.onGround() && !packet.isOnGround() && flag1) {