fix: use fork choice for parent payload status in block production

packages/beacon-node/src/chain/forkChoice/index.ts

@@ -150,7 +150,9 @@ export function initializeForkChoiceFromFinalizedState(
 
         ...(isStatePostBellatrix(state) && state.isExecutionStateType && state.isMergeTransitionComplete
           ? {
-              executionPayloadBlockHash: toRootHex(state.latestBlockHash),
+              executionPayloadBlockHash: isStatePostGloas(state)
+                ? toRootHex(state.latestBlockHash)
+                : toRootHex(state.latestExecutionPayloadHeader.blockHash),
               // TODO GLOAS: executionPayloadNumber is not tracked in BeaconState post-gloas (EIP-7732 removed
               // latestExecutionPayloadHeader). Using 0 as unavailable fallback until a solution is found.
               executionPayloadNumber: isStatePostGloas(state) ? 0 : state.payloadBlockNumber,
@@ -247,7 +249,9 @@ export function initializeForkChoiceFromUnfinalizedState(
     unfinalizedState.isExecutionStateType &&
     unfinalizedState.isMergeTransitionComplete
       ? {
-          executionPayloadBlockHash: toRootHex(unfinalizedState.latestBlockHash),
+          executionPayloadBlockHash: isStatePostGloas(unfinalizedState)
+            ? toRootHex(unfinalizedState.latestBlockHash)
+            : toRootHex(unfinalizedState.latestExecutionPayloadHeader.blockHash),
           // TODO GLOAS: executionPayloadNumber is not tracked in BeaconState post-gloas (EIP-7732 removed
           // latestExecutionPayloadHeader). Using 0 as unavailable fallback until a solution is found.
           executionPayloadNumber: isStatePostGloas(unfinalizedState) ? 0 : unfinalizedState.payloadBlockNumber,

packages/beacon-node/src/chain/prepareNextSlot.ts

@@ -8,9 +8,10 @@ import {
   computeEpochAtSlot,
   computeTimeAtSlot,
   isStatePostBellatrix,
+  isStatePostGloas,
 } from "@lodestar/state-transition";
-import {Slot} from "@lodestar/types";
-import {Logger, fromHex, isErrorAborted, sleep} from "@lodestar/utils";
+import {Bytes32, Slot} from "@lodestar/types";
+import {Logger, fromHex, isErrorAborted, sleep, toRootHex} from "@lodestar/utils";
 import {GENESIS_SLOT, ZERO_HASH_HEX} from "../constants/constants.js";
 import {BuilderStatus} from "../execution/builder/http.js";
 import {Metrics} from "../metrics/index.js";
@@ -156,25 +157,40 @@ export class PrepareNextSlotScheduler {
               this.logger.error("Builder disabled as the check status api failed", {prepareSlot}, e as Error);
             });
           }
+        }
+
+        if (!isStatePostBellatrix(updatedPrepareState)) {
+          throw new Error("Expected Bellatrix state for payload attributes");
+        }
+
+        const parentBlockRoot = fromHex(updatedHeadRoot);
+        let parentBlockHash: Bytes32;
+        if (isStatePostGloas(updatedPrepareState)) {
+          parentBlockHash = this.chain.forkChoice.shouldExtendPayload(toRootHex(parentBlockRoot))
+            ? updatedPrepareState.latestExecutionPayloadBid.blockHash
+            : updatedPrepareState.latestExecutionPayloadBid.parentBlockHash;
+        } else {
+          parentBlockHash = updatedPrepareState.latestExecutionPayloadHeader.blockHash;
+        }
 
+        if (feeRecipient) {
           const preparationTime =
             computeTimeAtSlot(this.config, prepareSlot, this.chain.genesisTime) - Date.now() / 1000;
           this.metrics?.blockPayload.payloadAdvancePrepTime.observe(preparationTime);
-          if (!isStatePostBellatrix(updatedPrepareState)) {
-            throw new Error("Expected Bellatrix state for payload preparation");
-          }
 
           const safeBlockHash = getSafeExecutionBlockHash(this.chain.forkChoice);
           const finalizedBlockHash =
             this.chain.forkChoice.getFinalizedBlock().executionPayloadBlockHash ?? ZERO_HASH_HEX;
+
           // awaiting here instead of throwing an async call because there is no other task
-          // left for scheduler and this gives nice sematics to catch and log errors in the
+          // left for scheduler and this gives nice semantics to catch and log errors in the
           // try/catch wrapper here.
           await prepareExecutionPayload(
             this.chain,
             this.logger,
             fork as ForkPostBellatrix, // State is of execution type
-            fromHex(updatedHeadRoot),
+            parentBlockRoot,
+            parentBlockHash,
             safeBlockHash,
             finalizedBlockHash,
             updatedPrepareState,
@@ -187,10 +203,6 @@ export class PrepareNextSlotScheduler {
           });
         }
 
-        if (!isStatePostBellatrix(updatedPrepareState)) {
-          throw new Error("Expected Bellatrix state for payload attributes");
-        }
-
         this.computeStateHashTreeRoot(updatedPrepareState, isEpochTransition);
 
         // If emitPayloadAttributes is true emit a SSE payloadAttributes event
@@ -201,7 +213,8 @@ export class PrepareNextSlotScheduler {
           const data = getPayloadAttributesForSSE(fork as ForkPostBellatrix, this.chain, {
             prepareState: updatedPrepareState,
             prepareSlot,
-            parentBlockRoot: fromHex(headRoot),
+            parentBlockRoot,
+            parentBlockHash,
             // The likely consumers of this API are builders and will anyway ignore the
             // feeRecipient, so just pass zero hash for now till a real use case arises
             feeRecipient: "0x0000000000000000000000000000000000000000000000000000000000000000",

packages/beacon-node/src/chain/produceBlock/produceBlockBody.ts

@@ -19,7 +19,6 @@ import {
   IBeaconStateView,
   type IBeaconStateViewBellatrix,
   computeTimeAtSlot,
-  isParentBlockFull,
   isStatePostBellatrix,
   isStatePostCapella,
   isStatePostGloas,
@@ -48,7 +47,7 @@ import {
   fulu,
   gloas,
 } from "@lodestar/types";
-import {Logger, fromHex, sleep, toHex, toPubkeyHex, toRootHex} from "@lodestar/utils";
+import {Logger, byteArrayEquals, fromHex, sleep, toHex, toPubkeyHex, toRootHex} from "@lodestar/utils";
 import {ZERO_HASH_HEX} from "../../constants/index.js";
 import {numToQuantity} from "../../execution/engine/utils.js";
 import {
@@ -214,11 +213,15 @@ export async function produceBlockBody<T extends BlockType>(
     });
 
     // Get execution payload from EL
+    const parentBlockHash = this.forkChoice.shouldExtendPayload(toRootHex(parentBlockRoot))
+      ? currentState.latestExecutionPayloadBid.blockHash
+      : currentState.latestExecutionPayloadBid.parentBlockHash;
     const prepareRes = await prepareExecutionPayload(
       this,
       this.logger,
       fork,
       parentBlockRoot,
+      parentBlockHash,
       safeBlockHash,
       finalizedBlockHash ?? ZERO_HASH_HEX,
       currentState,
@@ -255,8 +258,8 @@ export async function produceBlockBody<T extends BlockType>(
 
     // Create self-build execution payload bid
     const bid: gloas.ExecutionPayloadBid = {
-      parentBlockHash: currentState.latestBlockHash,
-      parentBlockRoot: parentBlockRoot,
+      parentBlockHash,
+      parentBlockRoot,
       blockHash: executionPayload.blockHash,
       prevRandao: currentState.getRandaoMix(currentState.epoch),
       feeRecipient: executionPayload.feeRecipient,
@@ -334,6 +337,7 @@ export async function produceBlockBody<T extends BlockType>(
             this.logger,
             fork,
             parentBlockRoot,
+            currentState.latestExecutionPayloadHeader.blockHash,
             safeBlockHash,
             finalizedBlockHash ?? ZERO_HASH_HEX,
             currentState,
@@ -442,6 +446,7 @@ export async function produceBlockBody<T extends BlockType>(
           this.logger,
           fork,
           parentBlockRoot,
+          currentState.latestExecutionPayloadHeader.blockHash,
           safeBlockHash,
           finalizedBlockHash ?? ZERO_HASH_HEX,
           currentState,
@@ -607,17 +612,17 @@ export async function prepareExecutionPayload(
   logger: Logger,
   fork: ForkPostBellatrix,
   parentBlockRoot: Root,
+  parentBlockHash: Bytes32,
   safeBlockHash: RootHex,
   finalizedBlockHash: RootHex,
   state: IBeaconStateViewBellatrix,
   suggestedFeeRecipient: string
 ): Promise<{prepType: PayloadPreparationType; payloadId: PayloadId}> {
-  const parentHash = state.latestBlockHash;
   const timestamp = computeTimeAtSlot(chain.config, state.slot, state.genesisTime);
   const prevRandao = state.getRandaoMix(state.epoch);
 
   const payloadIdCached = chain.executionEngine.payloadIdCache.get({
-    headBlockHash: toRootHex(parentHash),
+    headBlockHash: toRootHex(parentBlockHash),
     finalizedBlockHash,
     timestamp: numToQuantity(timestamp),
     prevRandao: toHex(prevRandao),
@@ -646,12 +651,13 @@ export async function prepareExecutionPayload(
       prepareState: state,
       prepareSlot: state.slot,
       parentBlockRoot,
+      parentBlockHash,
       feeRecipient: suggestedFeeRecipient,
     });
 
     payloadId = await chain.executionEngine.notifyForkchoiceUpdate(
       fork,
-      toRootHex(parentHash),
+      toRootHex(parentBlockHash),
       safeBlockHash,
       finalizedBlockHash,
       attributes
@@ -703,20 +709,30 @@ export function getPayloadAttributesForSSE(
     prepareState,
     prepareSlot,
     parentBlockRoot,
+    parentBlockHash,
     feeRecipient,
-  }: {prepareState: IBeaconStateViewBellatrix; prepareSlot: Slot; parentBlockRoot: Root; feeRecipient: string}
+  }: {
+    prepareState: IBeaconStateViewBellatrix;
+    prepareSlot: Slot;
+    parentBlockRoot: Root;
+    parentBlockHash: Bytes32;
+    feeRecipient: string;
+  }
 ): SSEPayloadAttributes {
-  const parentHash = prepareState.latestBlockHash;
   const payloadAttributes = preparePayloadAttributes(fork, chain, {
     prepareState,
     prepareSlot,
     parentBlockRoot,
+    parentBlockHash,
     feeRecipient,
   });
 
   let parentBlockNumber: number;
   if (isForkPostGloas(fork)) {
-    const parentBlock = chain.forkChoice.getBlockHexAndBlockHash(toRootHex(parentBlockRoot), toRootHex(parentHash));
+    const parentBlock = chain.forkChoice.getBlockHexAndBlockHash(
+      toRootHex(parentBlockRoot),
+      toRootHex(parentBlockHash)
+    );
     if (parentBlock?.executionPayloadBlockHash == null) {
       throw Error(`Parent block not found in fork choice root=${toRootHex(parentBlockRoot)}`);
     }
@@ -730,7 +746,7 @@ export function getPayloadAttributesForSSE(
     proposalSlot: prepareSlot,
     parentBlockNumber,
     parentBlockRoot,
-    parentBlockHash: parentHash,
+    parentBlockHash,
     payloadAttributes,
   };
   return ssePayloadAttributes;
@@ -745,11 +761,13 @@ function preparePayloadAttributes(
     prepareState,
     prepareSlot,
     parentBlockRoot,
+    parentBlockHash,
     feeRecipient,
   }: {
     prepareState: IBeaconStateViewBellatrix;
     prepareSlot: Slot;
     parentBlockRoot: Root;
+    parentBlockHash: Bytes32;
     feeRecipient: string;
   }
 ): SSEPayloadAttributes["payloadAttributes"] {
@@ -766,13 +784,15 @@ function preparePayloadAttributes(
       throw new Error("Expected Capella state for withdrawals");
     }
 
-    if (isStatePostGloas(prepareState) && !isParentBlockFull(prepareState)) {
+    if (isStatePostGloas(prepareState)) {
+      const isExtendingPayload = byteArrayEquals(parentBlockHash, prepareState.latestExecutionPayloadBid.blockHash);
       // When the parent block is empty, state.payloadExpectedWithdrawals holds a batch
       // already deducted from CL balances but never credited on the EL (the envelope
       // was not delivered). The next payload must carry those same withdrawals to
       // restore CL/EL consistency, otherwise validators permanently lose that balance.
-      (payloadAttributes as capella.SSEPayloadAttributes["payloadAttributes"]).withdrawals =
-        prepareState.payloadExpectedWithdrawals;
+      (payloadAttributes as capella.SSEPayloadAttributes["payloadAttributes"]).withdrawals = isExtendingPayload
+        ? prepareState.getExpectedWithdrawals().expectedWithdrawals
+        : prepareState.payloadExpectedWithdrawals;
     } else {
       // withdrawals logic is now fork aware as it changes on electra fork post capella
       (payloadAttributes as capella.SSEPayloadAttributes["payloadAttributes"]).withdrawals =

packages/beacon-node/src/node/nodejs.ts

@@ -6,7 +6,7 @@ import {BeaconApiMethods} from "@lodestar/api/beacon/server";
 import {BeaconConfig} from "@lodestar/config";
 import type {LoggerNode} from "@lodestar/logger/node";
 import {ZERO_HASH_HEX} from "@lodestar/params";
-import {IBeaconStateView, PubkeyCache, isStatePostBellatrix} from "@lodestar/state-transition";
+import {IBeaconStateView, PubkeyCache, isStatePostBellatrix, isStatePostGloas} from "@lodestar/state-transition";
 import {phase0} from "@lodestar/types";
 import {sleep, toRootHex} from "@lodestar/utils";
 import {ProcessShutdownCallback} from "@lodestar/validator";
@@ -223,7 +223,9 @@ export class BeaconNode {
     if (opts.executionEngine.mode === "mock") {
       const eth1BlockHash =
         isStatePostBellatrix(anchorState) && anchorState.isExecutionStateType
-          ? toRootHex(anchorState.latestBlockHash)
+          ? isStatePostGloas(anchorState)
+            ? toRootHex(anchorState.latestBlockHash)
+            : toRootHex(anchorState.latestExecutionPayloadHeader.blockHash)
           : undefined;
       executionEngineOpts = {
         ...opts.executionEngine,

packages/fork-choice/src/forkChoice/forkChoice.ts

@@ -311,6 +311,14 @@ export class ForkChoice implements IForkChoice {
     return this.proposerBoostRoot ?? HEX_ZERO_HASH;
   }
 
+  /**
+   * Decides whether to extend an available payload from the previous slot,
+   * corresponding to the beacon block `blockRoot`.
+   */
+  shouldExtendPayload(blockRoot: RootHex): boolean {
+    return this.protoArray.shouldExtendPayload(blockRoot, this.proposerBoostRoot);
+  }
+
   /**
    * To predict the proposer head of the next slot. That is, to predict if proposer-boost-reorg could happen.
    * Reason why we can't be certain is because information of the head block is not fully available yet

packages/fork-choice/src/forkChoice/interface.ts

@@ -241,6 +241,7 @@ export interface IForkChoice {
   getBlockDefaultStatus(blockRoot: Root): ProtoBlock | null;
   getBlockHexDefaultStatus(blockRoot: RootHex): ProtoBlock | null;
   getBlockHexAndBlockHash(blockRoot: RootHex, blockHash: RootHex): ProtoBlock | null;
+  shouldExtendPayload(blockRoot: RootHex): boolean;
   getFinalizedBlock(): ProtoBlock;
   getJustifiedBlock(): ProtoBlock;
   getFinalizedCheckpointSlot(): Slot;

packages/fork-choice/src/protoArray/protoArray.ts

@@ -707,7 +707,7 @@ export class ProtoArray {
    * Determine if we should extend the payload (prefer FULL over EMPTY)
    * Spec: gloas/fork-choice.md#new-should_extend_payload
    *
-   * Returns true if:
+   * Returns true if payload is verified (FULL variant exists) AND:
    * 1. Payload is timely, OR
    * 2. No proposer boost root (empty/zero hash), OR
    * 3. Proposer boost root's parent is not this block, OR
@@ -717,6 +717,10 @@ export class ProtoArray {
    * @param proposerBoostRoot - Current proposer boost root (from ForkChoice)
    */
   shouldExtendPayload(blockRoot: RootHex, proposerBoostRoot: RootHex | null): boolean {
+    if (!this.hasPayload(blockRoot)) {
+      return false;
+    }
+
     // Condition 1: Payload is timely
     if (this.isPayloadTimely(blockRoot)) {
       return true;