PaperMC/patches/server/0945-Fix-possible-StackOverflowError-for-some-dispenses.patch
Bjarne Koll c5a10665b8
Remove wall-time / unused skip tick protection (#11412)
Spigot still maintains some partial implementation of "tick skipping", a
practice in which the MinecraftServer.currentTick field is updated not
by an increment of one per actual tick, but instead set to
System.currentTimeMillis() / 50. This behaviour means that the tracked
tick may "skip" a tick value in case a previous tick took more than the
expected 50ms.

To compensate for this in important paths, spigot/craftbukkit
implements "wall-time". Instead of incrementing/decrementing ticks on
block entities/entities by one for each call to their tick() method,
they instead increment/decrement important values, like
an ItemEntity's age or pickupDelay, by the difference of
`currentTick - lastTick`, where `lastTick` is the value of
`currentTick` during the last tick() call.

These "fixes" however do not play nicely with minecraft's simulation
distance as entities/block entities implementing the above behaviour
would "catch up" their values when moving from a non-ticking chunk to a
ticking one as their `lastTick` value remains stuck on the last tick in
a ticking chunk and hence lead to a large "catch up" once ticked again.

Paper completely removes the "tick skipping" behaviour (See patch
"Further-improve-server-tick-loop"), making the above precautions
completely unnecessary, which also rids paper of the previous described
incompatibility with non-ticking chunks.
2024-09-19 16:36:07 +02:00

117 lines
8 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Sat, 29 Oct 2022 17:02:42 -0700
Subject: [PATCH] Fix possible StackOverflowError for some dispenses
For saddles, carpets, horse armor, and chests for horse-likes
a BlockDispenseEvent handler that always mutated the item without
changing the type would result in a SO error because when it went
to find the replacement dispense behavior (since the item "changed")
it didn't properly handle if the replacement was the same instance
of dispense behavior.
Additionally equippable mob heads, wither skulls, and carved pumpkins
are subject to the same possible error.
diff --git a/src/main/java/net/minecraft/core/dispenser/DispenseItemBehavior.java b/src/main/java/net/minecraft/core/dispenser/DispenseItemBehavior.java
index 7826e2a52da47914aca39fef958b8f398a2ff937..0c0b8a49b3342cd015381c6a93fab23c32cd32e6 100644
--- a/src/main/java/net/minecraft/core/dispenser/DispenseItemBehavior.java
+++ b/src/main/java/net/minecraft/core/dispenser/DispenseItemBehavior.java
@@ -239,7 +239,7 @@ public interface DispenseItemBehavior {
// Chain to handler for new item
ItemStack eventStack = CraftItemStack.asNMSCopy(event.getItem());
DispenseItemBehavior idispensebehavior = (DispenseItemBehavior) DispenserBlock.DISPENSER_REGISTRY.get(eventStack.getItem());
- if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != ArmorItem.DISPENSE_ITEM_BEHAVIOR) {
+ if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != this) { // Paper - fix possible StackOverflowError
idispensebehavior.dispense(pointer, eventStack);
return stack;
}
@@ -295,7 +295,7 @@ public interface DispenseItemBehavior {
// Chain to handler for new item
ItemStack eventStack = CraftItemStack.asNMSCopy(event.getItem());
DispenseItemBehavior idispensebehavior = (DispenseItemBehavior) DispenserBlock.DISPENSER_REGISTRY.get(eventStack.getItem());
- if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != ArmorItem.DISPENSE_ITEM_BEHAVIOR) {
+ if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != this) { // Paper - fix possible StackOverflowError
idispensebehavior.dispense(pointer, eventStack);
return stack;
}
@@ -369,7 +369,7 @@ public interface DispenseItemBehavior {
// Chain to handler for new item
ItemStack eventStack = CraftItemStack.asNMSCopy(event.getItem());
DispenseItemBehavior idispensebehavior = (DispenseItemBehavior) DispenserBlock.DISPENSER_REGISTRY.get(eventStack.getItem());
- if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != ArmorItem.DISPENSE_ITEM_BEHAVIOR) {
+ if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != this) { // Paper - fix possible StackOverflowError
idispensebehavior.dispense(pointer, eventStack);
return stack;
}
@@ -690,7 +690,7 @@ public interface DispenseItemBehavior {
OptionalDispenseItemBehavior dispensebehaviormaybe1 = new OptionalDispenseItemBehavior() {
@Override
protected ItemStack execute(BlockSource pointer, ItemStack stack) {
- this.setSuccess(ArmorItem.dispenseArmor(pointer, stack));
+ this.setSuccess(ArmorItem.dispenseArmor(pointer, stack, this)); // Paper - fix possible StackOverflowError
return stack;
}
};
@@ -744,7 +744,7 @@ public interface DispenseItemBehavior {
stack.shrink(1);
this.setSuccess(true);
} else {
- this.setSuccess(ArmorItem.dispenseArmor(pointer, stack));
+ this.setSuccess(ArmorItem.dispenseArmor(pointer, stack, this)); // Paper - fix possible StackOverflowError
}
return stack;
@@ -790,7 +790,7 @@ public interface DispenseItemBehavior {
stack.shrink(1);
this.setSuccess(true);
} else {
- this.setSuccess(ArmorItem.dispenseArmor(pointer, stack));
+ this.setSuccess(ArmorItem.dispenseArmor(pointer, stack, this)); // Paper - fix possible StackOverflowError
}
return stack;
@@ -918,7 +918,7 @@ public interface DispenseItemBehavior {
// Chain to handler for new item
ItemStack eventStack = CraftItemStack.asNMSCopy(event.getItem());
DispenseItemBehavior idispensebehavior = (DispenseItemBehavior) DispenserBlock.DISPENSER_REGISTRY.get(eventStack.getItem());
- if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != ArmorItem.DISPENSE_ITEM_BEHAVIOR) {
+ if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != this) { // Paper - fix possible StackOverflowError
idispensebehavior.dispense(pointer, eventStack);
return stack;
}
diff --git a/src/main/java/net/minecraft/world/item/ArmorItem.java b/src/main/java/net/minecraft/world/item/ArmorItem.java
index fb518f87cc4ccd810fb32cade2fdd7e09ab0abfc..647a4601deace52f8d855f512a73671f82b4762a 100644
--- a/src/main/java/net/minecraft/world/item/ArmorItem.java
+++ b/src/main/java/net/minecraft/world/item/ArmorItem.java
@@ -39,14 +39,20 @@ public class ArmorItem extends Item implements Equipable {
public static final DispenseItemBehavior DISPENSE_ITEM_BEHAVIOR = new DefaultDispenseItemBehavior() {
@Override
protected ItemStack execute(BlockSource pointer, ItemStack stack) {
- return ArmorItem.dispenseArmor(pointer, stack) ? stack : super.execute(pointer, stack);
+ return ArmorItem.dispenseArmor(pointer, stack, this) ? stack : super.execute(pointer, stack); // Paper - fix possible StackOverflowError
}
};
protected final ArmorItem.Type type;
protected final Holder<ArmorMaterial> material;
private final Supplier<ItemAttributeModifiers> defaultModifiers;
+ @Deprecated @io.papermc.paper.annotation.DoNotUse // Paper
public static boolean dispenseArmor(BlockSource pointer, ItemStack armor) {
+ // Paper start
+ return dispenseArmor(pointer, armor, null);
+ }
+ public static boolean dispenseArmor(BlockSource pointer, ItemStack armor, @javax.annotation.Nullable DispenseItemBehavior currentBehavior) {
+ // Paper end
BlockPos blockposition = pointer.pos().relative((Direction) pointer.state().getValue(DispenserBlock.FACING));
List<LivingEntity> list = pointer.level().getEntitiesOfClass(LivingEntity.class, new AABB(blockposition), EntitySelector.NO_SPECTATORS.and(new EntitySelector.MobCanWearArmorEntitySelector(armor)));
@@ -77,7 +83,7 @@ public class ArmorItem extends Item implements Equipable {
// Chain to handler for new item
ItemStack eventStack = CraftItemStack.asNMSCopy(event.getItem());
DispenseItemBehavior idispensebehavior = (DispenseItemBehavior) DispenserBlock.DISPENSER_REGISTRY.get(eventStack.getItem());
- if (idispensebehavior != DispenseItemBehavior.NOOP && idispensebehavior != ArmorItem.DISPENSE_ITEM_BEHAVIOR) {
+ if (idispensebehavior != DispenseItemBehavior.NOOP && (currentBehavior == null || idispensebehavior != currentBehavior)) { // Paper - fix possible StackOverflowError
idispensebehavior.dispense(pointer, eventStack);
return true;
}