From fd1ca8ef23448b9295bf405313e02337eff453f1 Mon Sep 17 00:00:00 2001
From: Michael Sproul <michael@sigmaprime.io>
Date: Tue, 25 Feb 2025 23:30:02 +1100
Subject: [PATCH] Ban peers with banned payloads

---
 .../src/network_beacon_processor/sync_methods.rs     | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/beacon_node/network/src/network_beacon_processor/sync_methods.rs b/beacon_node/network/src/network_beacon_processor/sync_methods.rs
index 338f2bc4c8..ef4d9cc4c1 100644
--- a/beacon_node/network/src/network_beacon_processor/sync_methods.rs
+++ b/beacon_node/network/src/network_beacon_processor/sync_methods.rs
@@ -800,6 +800,18 @@ impl<T: BeaconChainTypes> NetworkBeaconProcessor<T> {
                     peer_action: Some(PeerAction::LowToleranceError),
                 })
             }
+            // Penalise peers for sending us banned blocks.
+            BlockError::KnownInvalidExecutionPayload(block_root) => {
+                warn!(
+                    self.log,
+                    "Received block known to be invalid";
+                    "block_root" => ?block_root,
+                );
+                Err(ChainSegmentFailed {
+                    message: format!("Banned block: {block_root:?}"),
+                    peer_action: Some(PeerAction::LowToleranceError),
+                })
+            }
             other => {
                 debug!(
                     self.log, "Invalid block received";