Limit recursive block updates to prevent stack overflow crashes (#424)

* Limit recursive block updates to prevent stack overflow crashes

* Review comments

src/main/java/com/mitchej123/hodgepodge/config/FixesConfig.java

@@ -352,6 +352,12 @@ public class FixesConfig {
  @Config.RequiresMcRestart
  public static boolean fixCaseCommands;
 
+ @Config.Comment("Limit the number of recursive cascading block updates during world generation to prevent stack overflow crashes, set to -1 to disable the limit.")
+ @Config.RangeInt(min = -1)
+ @Config.DefaultInt(256) // A stack overflow with water updates happens somewhere above 300 updates with default Java
+ // settings
+ public static int limitRecursiveBlockUpdateDepth;
+
  // affecting multiple mods
 
  @Config.Comment("Remove old/stale/outdated update checks.")

src/main/java/com/mitchej123/hodgepodge/mixins/Mixins.java

@@ -421,6 +421,12 @@ public enum Mixins {
  .setPhase(Phase.EARLY).setSide(Side.BOTH).addTargetedMod(TargetedMod.VANILLA)
  .addMixinClasses("minecraft.MixinCommandHandler_CommandFix").setApplyIf(() -> FixesConfig.fixCaseCommands)),
 
+ LIMIT_RECURSIVE_BLOCK_UPDATE_DEPTH(new Builder(
+ "Limit the number of recursive cascading block updates during world generation to prevent stack overflow crashes")
+ .setPhase(Phase.EARLY).setSide(Side.BOTH).addTargetedMod(TargetedMod.VANILLA)
+ .addMixinClasses("minecraft.MixinWorldServer_LimitUpdateRecursion")
+ .setApplyIf(() -> FixesConfig.limitRecursiveBlockUpdateDepth >= 0)),
+
  // Ic2 adjustments
  IC2_UNPROTECTED_GET_BLOCK_FIX(new Builder("IC2 Kinetic Fix").setPhase(Phase.EARLY).setSide(Side.BOTH)
  .addMixinClasses("ic2.MixinIc2WaterKinetic").setApplyIf(() -> FixesConfig.fixIc2UnprotectedGetBlock)

src/main/java/com/mitchej123/hodgepodge/mixins/early/minecraft/MixinWorldServer_LimitUpdateRecursion.java

@@ -0,0 +1,46 @@
+package com.mitchej123.hodgepodge.mixins.early.minecraft;
+
+import net.minecraft.block.Block;
+import net.minecraft.world.WorldServer;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Unique;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import com.mitchej123.hodgepodge.Common;
+import com.mitchej123.hodgepodge.config.FixesConfig;
+
+@Mixin(WorldServer.class)
+public class MixinWorldServer_LimitUpdateRecursion {
+
+ @Unique
+ private int hodgepodge$currentBlockUpdateRecursiveCalls = 0;
+
+ @Inject(method = "scheduleBlockUpdateWithPriority", at = @At("HEAD"), cancellable = true)
+ private void hodgepodge$incrementBlockUpdateRecursionCounter(int x, int y, int z, Block block, int tickDelay,
+ int priority, CallbackInfo ci) {
+ if (hodgepodge$currentBlockUpdateRecursiveCalls >= FixesConfig.limitRecursiveBlockUpdateDepth) {
+ final StackOverflowError error = new StackOverflowError(
+ String.format(
+ "Too many recursive block updates (%d) at world %d, block %s (%d, %d, %d) - aborting further block updates",
+ hodgepodge$currentBlockUpdateRecursiveCalls,
+ ((WorldServer) (Object) this).provider.dimensionId,
+ block,
+ x,
+ y,
+ z));
+ Common.log.error(error.getMessage(), error);
+ ci.cancel();
+ return;
+ }
+ hodgepodge$currentBlockUpdateRecursiveCalls++;
+ }
+
+ @Inject(method = "scheduleBlockUpdateWithPriority", at = @At("RETURN"))
+ private void hodgepodge$decrementBlockUpdateRecursionCounter(int x, int y, int z, Block block, int tickDelay,
+ int priority, CallbackInfo ci) {
+ hodgepodge$currentBlockUpdateRecursiveCalls = Math.max(0, hodgepodge$currentBlockUpdateRecursiveCalls - 1);
+ }
+}