fix(p2p): use projected next-block fees in gossip validator instead of stale block header

The gossip validator was checking tx maxFeePerGas against the last block's
header fees, while the wallet and tx pool already use projected next-block
fees from L1. When the L1 fee oracle transitions from high to low values
(e.g. after a time warp in tests), this caused a large discrepancy where
valid transactions were rejected at the gossip layer.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: spalladino

yarn-project/p2p/src/client/factory.ts

@@ -142,6 +142,7 @@ export async function createP2PClient(
     proofVerifier,
     worldStateSynchronizer,
     epochCache,
+    blockMinFeesProvider,
     store,
     peerStore,
     mempools,
@@ -218,6 +219,7 @@ async function createP2PService(
   proofVerifier: ClientProtocolCircuitVerifier,
   worldStateSynchronizer: WorldStateSynchronizer,
   epochCache: EpochCacheInterface,
+  blockMinFeesProvider: BlockMinFeesProvider,
   store: AztecAsyncKVStore,
   peerStore: AztecLMDBStoreV2,
   mempools: MemPools,
@@ -245,6 +247,7 @@ async function createP2PService(
     proofVerifier,
     worldStateSynchronizer,
     peerStore,
+    blockMinFeesProvider,
     telemetry,
     logger: logger.createChild(`libp2p_service`),
   });

yarn-project/p2p/src/services/libp2p/libp2p_service.test.ts

@@ -8,6 +8,7 @@ import { type Logger, createLogger } from '@aztec/foundation/log';
 import { openTmpStore } from '@aztec/kv-store/lmdb';
 import { L2Block, type L2BlockSource } from '@aztec/stdlib/block';
 import type { ContractDataSource } from '@aztec/stdlib/contract';
+import { GasFees } from '@aztec/stdlib/gas';
 import type { ClientProtocolCircuitVerifier } from '@aztec/stdlib/interfaces/server';
 import { BlockProposal, PeerErrorSeverity } from '@aztec/stdlib/p2p';
 import {
@@ -1117,6 +1118,7 @@ describe('LibP2PService', () => {
         epochCache,
         mockProofVerifier,
         mockWorldStateSynchronizer,
+        { getCurrentMinFees: () => Promise.resolve(GasFees.empty()) },
         getTelemetryClient(),
         createLogger('p2p:test:queryForIp'),
       );
@@ -1264,6 +1266,7 @@ class TestLibP2PService extends LibP2PService {
       epochCache,
       mockProofVerifier,
       mockWorldStateSynchronizer,
+      { getCurrentMinFees: () => Promise.resolve(GasFees.empty()) },
       telemetry,
       logger,
     );

yarn-project/p2p/src/services/libp2p/libp2p_service.ts

@@ -9,7 +9,7 @@ import type { AztecAsyncKVStore } from '@aztec/kv-store';
 import { protocolContractsHash } from '@aztec/protocol-contracts';
 import type { EthAddress, L2Block, L2BlockSource } from '@aztec/stdlib/block';
 import type { ContractDataSource } from '@aztec/stdlib/contract';
-import { GasFees } from '@aztec/stdlib/gas';
+import { type BlockMinFeesProvider, GasFees } from '@aztec/stdlib/gas';
 import type { ClientProtocolCircuitVerifier, PeerInfo, WorldStateSynchronizer } from '@aztec/stdlib/interfaces/server';
 import {
   BlockProposal,
@@ -148,8 +148,6 @@ export class LibP2PService extends WithTracer implements P2PService {
   private protocolVersion = '';
   private topicStrings: Record<TopicType, string> = {} as Record<TopicType, string>;
 
-  private feesCache: { blockNumber: BlockNumber; gasFees: GasFees } | undefined;
-
   /** Callback invoked when a duplicate proposal is detected (triggers slashing). */
   private duplicateProposalCallback?: (info: {
     slot: SlotNumber;
@@ -197,6 +195,7 @@ export class LibP2PService extends WithTracer implements P2PService {
     private epochCache: EpochCacheInterface,
     private proofVerifier: ClientProtocolCircuitVerifier,
     private worldStateSynchronizer: WorldStateSynchronizer,
+    private blockMinFeesProvider: BlockMinFeesProvider,
     telemetry: TelemetryClient,
     logger: Logger = createLogger('p2p:libp2p_service'),
   ) {
@@ -278,6 +277,7 @@ export class LibP2PService extends WithTracer implements P2PService {
       proofVerifier: ClientProtocolCircuitVerifier;
       worldStateSynchronizer: WorldStateSynchronizer;
       peerStore: AztecAsyncKVStore;
+      blockMinFeesProvider: BlockMinFeesProvider;
       telemetry: TelemetryClient;
       logger: Logger;
       packageVersion: string;
@@ -290,6 +290,7 @@ export class LibP2PService extends WithTracer implements P2PService {
       mempools,
       proofVerifier,
       peerStore,
+      blockMinFeesProvider,
       telemetry,
       logger,
       packageVersion,
@@ -491,6 +492,7 @@ export class LibP2PService extends WithTracer implements P2PService {
       epochCache,
       proofVerifier,
       worldStateSynchronizer,
+      blockMinFeesProvider,
       telemetry,
       logger,
     );
@@ -1664,15 +1666,8 @@ export class LibP2PService extends WithTracer implements P2PService {
     });
   }
 
-  private async getGasFees(blockNumber: BlockNumber): Promise<GasFees> {
-    if (blockNumber === this.feesCache?.blockNumber) {
-      return this.feesCache.gasFees;
-    }
-
-    const header = await this.archiver.getBlockHeader(blockNumber);
-    const gasFees = header?.globalVariables.gasFees ?? GasFees.empty();
-    this.feesCache = { blockNumber, gasFees };
-    return gasFees;
+  private getGasFees(): Promise<GasFees> {
+    return this.blockMinFeesProvider.getCurrentMinFees();
   }
 
   /**
@@ -1714,7 +1709,7 @@ export class LibP2PService extends WithTracer implements P2PService {
     currentBlockNumber: BlockNumber,
     nextSlotTimestamp: UInt64,
   ): Promise<Record<string, TransactionValidator>> {
-    const gasFees = await this.getGasFees(currentBlockNumber);
+    const gasFees = await this.getGasFees();
     const allowedInSetup = [
       ...(await getDefaultAllowedSetupFunctions()),
       ...(this.config.txPublicSetupAllowListExtend ?? []),

yarn-project/p2p/src/test-helpers/mock-pubsub.ts

@@ -3,6 +3,7 @@ import { type Logger, createLogger } from '@aztec/foundation/log';
 import type { AztecAsyncKVStore } from '@aztec/kv-store';
 import type { L2BlockSource } from '@aztec/stdlib/block';
 import type { ContractDataSource } from '@aztec/stdlib/contract';
+import type { BlockMinFeesProvider } from '@aztec/stdlib/gas';
 import type { ClientProtocolCircuitVerifier, WorldStateSynchronizer } from '@aztec/stdlib/interfaces/server';
 import type { TelemetryClient } from '@aztec/telemetry-client';
 
@@ -56,6 +57,7 @@ export function getMockPubSubP2PServiceFactory(
       proofVerifier: ClientProtocolCircuitVerifier;
       worldStateSynchronizer: WorldStateSynchronizer;
       peerStore: AztecAsyncKVStore;
+      blockMinFeesProvider: BlockMinFeesProvider;
       telemetry: TelemetryClient;
       logger: Logger;
     },
@@ -76,6 +78,7 @@ export function getMockPubSubP2PServiceFactory(
       deps.epochCache,
       deps.proofVerifier,
       deps.worldStateSynchronizer,
+      deps.blockMinFeesProvider,
       deps.telemetry,
       deps.logger,
     );

yarn-project/p2p/src/test-helpers/reqresp-nodes.ts

@@ -6,6 +6,7 @@ import { openTmpStore } from '@aztec/kv-store/lmdb-v2';
 import type { L2BlockSource } from '@aztec/stdlib/block';
 import { type ChainConfig, emptyChainConfig } from '@aztec/stdlib/config';
 import type { ContractDataSource } from '@aztec/stdlib/contract';
+import { GasFees } from '@aztec/stdlib/gas';
 import type {
   ClientProtocolCircuitVerifier,
   IVCProofVerificationResult,
@@ -168,6 +169,7 @@ export async function createTestLibP2PService(
     epochCache,
     proofVerifier,
     worldStateSynchronizer,
+    { getCurrentMinFees: () => Promise.resolve(GasFees.empty()) },
     telemetry,
   );
 }

yarn-project/p2p/src/testbench/p2p_client_testbench_worker.ts

@@ -117,6 +117,7 @@ class TestLibP2PService extends LibP2PService {
       epochCache,
       proofVerifier,
       worldStateSynchronizer,
+      { getCurrentMinFees: () => Promise.resolve(GasFees.empty()) },
       telemetry,
       logger,
     );