Patch

1 files changed, 154 insertions, 0 deletions

diff --git a/patches/server/0344-Fix-item-duplication-and-teleport-issues.patch b/patches/server/0344-Fix-item-duplication-and-teleport-issues.patch
new file mode 100644
index 0000000000..1e7965da69
--- /dev/null
+++ b/patches/server/0344-Fix-item-duplication-and-teleport-issues.patch
@@ -0,0 +1,154 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <[email protected]>
+Date: Sat, 25 Apr 2020 06:46:35 -0400
+Subject: [PATCH] Fix item duplication and teleport issues
+
+This notably fixes the newest "Donkey Dupe", but also fixes a lot
+of dupe bugs in general around nether portals and entity world transfer
+
+We also fix item duplication generically by anytime we clone an item
+to drop it on the ground, destroy the source item.
+
+This avoid an itemstack ever existing twice in the world state pre
+clean up stage.
+
+So even if something NEW comes up, it would be impossible to drop the
+same item twice because the source was destroyed.
+
+diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
+index 5b8e264098f1b713de15f714bae59d3efda365cf..4faba83eb73e0d313e9131794962b727f7628a50 100644
+--- a/src/main/java/net/minecraft/world/entity/Entity.java
++++ b/src/main/java/net/minecraft/world/entity/Entity.java
+@@ -2630,11 +2630,12 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
+         } else {
+             // CraftBukkit start - Capture drops for death event
+             if (this instanceof net.minecraft.world.entity.LivingEntity && !((net.minecraft.world.entity.LivingEntity) this).forceDrops) {
+-                ((net.minecraft.world.entity.LivingEntity) this).drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asBukkitCopy(stack));
++                ((net.minecraft.world.entity.LivingEntity) this).drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asCraftMirror(stack)); // Paper - mirror so we can destroy it later
+                 return null;
+             }
+             // CraftBukkit end
+             ItemEntity entityitem = new ItemEntity(world, this.getX(), this.getY() + (double) yOffset, this.getZ(), stack);
++            stack.setCount(0); // Paper - destroy this item - if this ever leaks due to game bugs, ensure it doesn't dupe
+ 
+             entityitem.setDefaultPickUpDelay();
+             // CraftBukkit start
+@@ -3462,6 +3463,12 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
+     public Entity teleport(TeleportTransition teleportTarget) {
+         Level world = this.level();
+ 
++        // Paper start - Fix item duplication and teleport issues
++        if (!this.isAlive() || !this.valid) {
++            LOGGER.warn("Illegal Entity Teleport " + this + " to " + teleportTarget.newLevel() + ":" + teleportTarget.pos(), new Throwable());
++            return null;
++        }
++        // Paper end - Fix item duplication and teleport issues
+         if (world instanceof ServerLevel worldserver) {
+             if (!this.isRemoved()) {
+                 // CraftBukkit start
+@@ -3550,6 +3557,11 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
+             gameprofilerfiller.pop();
+             return null;
+         } else {
++            // Paper start - Fix item duplication and teleport issues
++            if (this instanceof Leashable leashable) {
++                leashable.dropLeash(true, true); // Paper drop lead
++            }
++            // Paper end - Fix item duplication and teleport issues
+             entity.restoreFrom(this);
+             this.removeAfterChangingDimensions();
+             // CraftBukkit start - Forward the CraftEntity to the new entity
+@@ -3662,6 +3674,7 @@ public abstract class Entity implements SyncedDataHolder, Nameable, EntityAccess
+     }
+ 
+     public boolean canTeleport(Level from, Level to) {
++        if (!this.isAlive() || !this.valid) return false; // Paper - Fix item duplication and teleport issues
+         if (from.dimension() == Level.END && to.dimension() == Level.OVERWORLD) {
+             Iterator iterator = this.getPassengers().iterator();
+ 
+diff --git a/src/main/java/net/minecraft/world/entity/LivingEntity.java b/src/main/java/net/minecraft/world/entity/LivingEntity.java
+index 68e5f6f7013d6a014b9014d945cf3f7dc7a37cb2..65909e0a8f8b68f9a4dacefda9069c8263a96ada 100644
+--- a/src/main/java/net/minecraft/world/entity/LivingEntity.java
++++ b/src/main/java/net/minecraft/world/entity/LivingEntity.java
+@@ -1767,9 +1767,9 @@ public abstract class LivingEntity extends Entity implements Attackable {
+                 // Paper start
+                 org.bukkit.event.entity.EntityDeathEvent deathEvent = this.dropAllDeathLoot(worldserver, damageSource);
+                 if (deathEvent == null || !deathEvent.isCancelled()) {
+-                    if (this.deathScore >= 0 && entityliving != null) {
+-                        entityliving.awardKillScore(this, this.deathScore, damageSource);
+-                    }
++                    // if (this.deathScore >= 0 && entityliving != null) { // Paper - Fix item duplication and teleport issues; moved to be run earlier in #dropAllDeathLoot before destroying the drop items in CraftEventFactory#callEntityDeathEvent
++                    //     entityliving.awardKillScore(this, this.deathScore, damageSource);
++                    // }
+                     // Paper start - clear equipment if event is not cancelled
+                     if (this instanceof Mob) {
+                         for (EquipmentSlot slot : this.clearedEquipmentSlots) {
+@@ -1863,8 +1863,13 @@ public abstract class LivingEntity extends Entity implements Attackable {
+             this.dropCustomDeathLoot(world, damageSource, flag);
+             this.clearEquipmentSlots = prev; // Paper
+         }
+-        // CraftBukkit start - Call death event
+-        org.bukkit.event.entity.EntityDeathEvent deathEvent = CraftEventFactory.callEntityDeathEvent(this, damageSource, this.drops); // Paper
++        // CraftBukkit start - Call death event // Paper start - call advancement triggers with correct entity equipment
++        org.bukkit.event.entity.EntityDeathEvent deathEvent = CraftEventFactory.callEntityDeathEvent(this, damageSource, this.drops, () -> {
++            final LivingEntity entityliving = this.getKillCredit();
++            if (this.deathScore >= 0 && entityliving != null) {
++                entityliving.awardKillScore(this, this.deathScore, damageSource);
++            }
++        }); // Paper end
+         this.postDeathDropItems(deathEvent); // Paper
+         this.drops = new ArrayList<>();
+         // CraftBukkit end
+diff --git a/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java b/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
+index e20565cf256aacd012a1722c5ebbf9016bc82e42..59fbfe8de2dc5ec020dd61a5e446b0b6f67d76e4 100644
+--- a/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
++++ b/src/main/java/net/minecraft/world/entity/decoration/ArmorStand.java
+@@ -633,7 +633,7 @@ public class ArmorStand extends LivingEntity {
+         for (i = 0; i < this.handItems.size(); ++i) {
+             itemstack = (ItemStack) this.handItems.get(i);
+             if (!itemstack.isEmpty()) {
+-                this.drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asBukkitCopy(itemstack)); // CraftBukkit - add to drops
++                this.drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asCraftMirror(itemstack)); // CraftBukkit - add to drops // Paper - mirror so we can destroy it later - though this call site was safe
+                 this.handItems.set(i, ItemStack.EMPTY);
+             }
+         }
+@@ -641,7 +641,7 @@ public class ArmorStand extends LivingEntity {
+         for (i = 0; i < this.armorItems.size(); ++i) {
+             itemstack = (ItemStack) this.armorItems.get(i);
+             if (!itemstack.isEmpty()) {
+-                this.drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asBukkitCopy(itemstack)); // CraftBukkit - add to drops
++                this.drops.add(org.bukkit.craftbukkit.inventory.CraftItemStack.asCraftMirror(itemstack)); // CraftBukkit - add to drops // Paper - mirror so we can destroy it later - though this call site was safe
+                 this.armorItems.set(i, ItemStack.EMPTY);
+             }
+         }
+diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+index 41f23ce732b6e90828b1bbda7f4b3470cd462c4a..0b9c96105bea9a0d1af17b7ecf4479d3596faa80 100644
+--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
++++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+@@ -903,6 +903,11 @@ public class CraftEventFactory {
+     }
+ 
+     public static EntityDeathEvent callEntityDeathEvent(net.minecraft.world.entity.LivingEntity victim, DamageSource damageSource, List<org.bukkit.inventory.ItemStack> drops) {
++        // Paper start
++        return CraftEventFactory.callEntityDeathEvent(victim, damageSource, drops, com.google.common.util.concurrent.Runnables.doNothing());
++    }
++    public static EntityDeathEvent callEntityDeathEvent(net.minecraft.world.entity.LivingEntity victim, DamageSource damageSource, List<org.bukkit.inventory.ItemStack> drops, Runnable lootCheck) {
++        // Paper end
+         CraftLivingEntity entity = (CraftLivingEntity) victim.getBukkitEntity();
+         CraftDamageSource bukkitDamageSource = new CraftDamageSource(damageSource);
+         CraftWorld world = (CraftWorld) entity.getWorld();
+@@ -917,11 +922,13 @@ public class CraftEventFactory {
+         playDeathSound(victim, event);
+         // Paper end
+         victim.expToDrop = event.getDroppedExp();
++        lootCheck.run(); // Paper - advancement triggers before destroying items
+ 
+         for (org.bukkit.inventory.ItemStack stack : event.getDrops()) {
+             if (stack == null || stack.getType() == Material.AIR || stack.getAmount() == 0) continue;
+ 
+-            world.dropItem(entity.getLocation(), stack);
++            world.dropItem(entity.getLocation(), stack); // Paper - note: dropItem already clones due to this being bukkit -> NMS
++            if (stack instanceof CraftItemStack) stack.setAmount(0); // Paper - destroy this item - if this ever leaks due to game bugs, ensure it doesn't dupe, but don't nuke bukkit stacks of manually added items
+         }
+ 
+         return event;