From d8e359a7b652ccb68f3316ec2d9dac1fd9016e80 Mon Sep 17 00:00:00 2001
From: Eitan Seri-Levi <eserilev@ucsc.edu>
Date: Thu, 7 May 2026 12:37:03 +0300
Subject: [PATCH] Prevent chain stall

---
 beacon_node/beacon_chain/src/block_verification.rs | 10 ++++++----
 beacon_node/network/src/sync/block_lookups/mod.rs  |  7 +------
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/beacon_node/beacon_chain/src/block_verification.rs b/beacon_node/beacon_chain/src/block_verification.rs
index 84df30e75f..24aae7b999 100644
--- a/beacon_node/beacon_chain/src/block_verification.rs
+++ b/beacon_node/beacon_chain/src/block_verification.rs
@@ -930,16 +930,17 @@ impl<T: BeaconChainTypes> GossipVerifiedBlock<T> {
         let (parent_block, block) =
             verify_parent_block_is_known::<T>(&fork_choice_read_lock, block)?;
 
+        let Ok(bid) = block.message().body().signed_execution_payload_bid() else {
+            return Err(BlockError::InternalError("Invalid variant".to_string()));
+        };
+
         // [New in Gloas]: Verify bid.parent_block_root matches block.parent_root.
-        if let Ok(bid) = block.message().body().signed_execution_payload_bid()
-            && bid.message.parent_block_root != block.message().parent_root()
-        {
+        if bid.message.parent_block_root != block.message().parent_root() {
             return Err(BlockError::BidParentRootMismatch {
                 bid_parent_root: bid.message.parent_block_root,
                 block_parent_root: block.message().parent_root(),
             });
         }
-
         // Check that we've received the parent envelope. If not, issue a single envelope
         // lookup for the parent and queue this block in the reprocess queue.
         //
@@ -955,6 +956,7 @@ impl<T: BeaconChainTypes> GossipVerifiedBlock<T> {
         if parent_is_gloas
             && !parent_is_anchor
             && !fork_choice_read_lock.is_payload_received(&block.message().parent_root())
+            && Some(bid.message.parent_block_hash) != parent_block.execution_payload_block_hash
         {
             return Err(BlockError::ParentEnvelopeUnknown {
                 parent_root: block.message().parent_root(),
diff --git a/beacon_node/network/src/sync/block_lookups/mod.rs b/beacon_node/network/src/sync/block_lookups/mod.rs
index bb003dc222..a9d08c30a4 100644
--- a/beacon_node/network/src/sync/block_lookups/mod.rs
+++ b/beacon_node/network/src/sync/block_lookups/mod.rs
@@ -662,12 +662,7 @@ impl<T: BeaconChainTypes> BlockLookups<T> {
                         "Envelope processed, transitioning to custody column lookup"
                     );
                     let lookup_result = lookup.continue_requests(cx);
-                    self.on_lookup_result(
-                        id,
-                        lookup_result,
-                        "envelope_to_custody_transition",
-                        cx,
-                    );
+                    self.on_lookup_result(id, lookup_result, "envelope_to_custody_transition", cx);
                     return;
                 }