From d584aed680aafedec56e19a77162a847bbd21a33 Mon Sep 17 00:00:00 2001
From: Nico Flaig <nflaig@protonmail.com>
Date: Mon, 20 Jan 2025 21:30:44 +0000
Subject: [PATCH] fix: consistently check no pending withdrawals when
 processing voluntary exit (#7379)

* fix: consistently check no pending withdrawals when processing voluntary exit

* Lint
---
 .../beacon-node/src/chain/opPools/opPool.ts   |  2 +-
 .../src/chain/validation/voluntaryExit.ts     |  2 +-
 .../src/block/processVoluntaryExit.ts         | 27 ++++++-------------
 3 files changed, 10 insertions(+), 21 deletions(-)

diff --git a/packages/beacon-node/src/chain/opPools/opPool.ts b/packages/beacon-node/src/chain/opPools/opPool.ts
index 5eec1597a24e..819873d2e835 100644
--- a/packages/beacon-node/src/chain/opPools/opPool.ts
+++ b/packages/beacon-node/src/chain/opPools/opPool.ts
@@ -247,7 +247,7 @@ export class OpPool {
     for (const voluntaryExit of this.voluntaryExits.values()) {
       if (
         !toBeSlashedIndices.has(voluntaryExit.message.validatorIndex) &&
-        isValidVoluntaryExit(state, voluntaryExit, false) &&
+        isValidVoluntaryExit(stateFork, state, voluntaryExit, false) &&
         // Signature validation is skipped in `isValidVoluntaryExit(,,false)` since it was already validated in gossip
         // However we must make sure that the signature fork is the same, or it will become invalid if included through
         // a future fork.
diff --git a/packages/beacon-node/src/chain/validation/voluntaryExit.ts b/packages/beacon-node/src/chain/validation/voluntaryExit.ts
index 79da31084a36..60ee133e4b69 100644
--- a/packages/beacon-node/src/chain/validation/voluntaryExit.ts
+++ b/packages/beacon-node/src/chain/validation/voluntaryExit.ts
@@ -43,7 +43,7 @@ async function validateVoluntaryExit(
 
   // [REJECT] All of the conditions within process_voluntary_exit pass validation.
   // verifySignature = false, verified in batch below
-  if (!isValidVoluntaryExit(state, voluntaryExit, false)) {
+  if (!isValidVoluntaryExit(chain.config.getForkSeq(state.slot), state, voluntaryExit, false)) {
     throw new VoluntaryExitError(GossipAction.REJECT, {
       code: VoluntaryExitErrorCode.INVALID,
     });
diff --git a/packages/state-transition/src/block/processVoluntaryExit.ts b/packages/state-transition/src/block/processVoluntaryExit.ts
index a0a0271a0d1e..3cc6afb958f8 100644
--- a/packages/state-transition/src/block/processVoluntaryExit.ts
+++ b/packages/state-transition/src/block/processVoluntaryExit.ts
@@ -1,5 +1,5 @@
 import {FAR_FUTURE_EPOCH, ForkSeq} from "@lodestar/params";
-import {phase0} from "@lodestar/types";
+import {ValidatorIndex, phase0} from "@lodestar/types";
 import {verifyVoluntaryExitSignature} from "../signatureSets/index.js";
 import {CachedBeaconStateAllForks, CachedBeaconStateElectra} from "../types.js";
 import {getPendingBalanceToWithdraw, isActiveValidator} from "../util/index.js";
@@ -16,11 +16,7 @@ export function processVoluntaryExit(
   signedVoluntaryExit: phase0.SignedVoluntaryExit,
   verifySignature = true
 ): void {
-  const isValidExit =
-    fork >= ForkSeq.electra
-      ? isValidVoluntaryExitElectra(state as CachedBeaconStateElectra, signedVoluntaryExit, verifySignature)
-      : isValidVoluntaryExit(state, signedVoluntaryExit, verifySignature);
-  if (!isValidExit) {
+  if (!isValidVoluntaryExit(fork, state, signedVoluntaryExit, verifySignature)) {
     throw Error(`Invalid voluntary exit at forkSeq=${fork}`);
   }
 
@@ -29,6 +25,7 @@ export function processVoluntaryExit(
 }
 
 export function isValidVoluntaryExit(
+  fork: ForkSeq,
   state: CachedBeaconStateAllForks,
   signedVoluntaryExit: phase0.SignedVoluntaryExit,
   verifySignature = true
@@ -47,20 +44,12 @@ export function isValidVoluntaryExit(
     currentEpoch >= voluntaryExit.epoch &&
     // verify the validator had been active long enough
     currentEpoch >= validator.activationEpoch + config.SHARD_COMMITTEE_PERIOD &&
+    (fork >= ForkSeq.electra
+      ? // only exit validator if it has no pending withdrawals in the queue
+        getPendingBalanceToWithdraw(state as CachedBeaconStateElectra, voluntaryExit.validatorIndex) === 0
+      : // there are no pending withdrawals in previous forks
+        true) &&
     // verify signature
     (!verifySignature || verifyVoluntaryExitSignature(state, signedVoluntaryExit))
   );
 }
-
-function isValidVoluntaryExitElectra(
-  state: CachedBeaconStateElectra,
-  signedVoluntaryExit: phase0.SignedVoluntaryExit,
-  verifySignature = true
-): boolean {
-  // only exit validator if it has no pending withdrawals in the queue (post-Electra only)
-  if (getPendingBalanceToWithdraw(state, signedVoluntaryExit.message.validatorIndex) === 0) {
-    return isValidVoluntaryExit(state, signedVoluntaryExit, verifySignature);
-  }
-
-  return false;
-}