Fix

Author: flcl42

src/Nethermind/Nethermind.Blockchain.Test/BlockProcessorTests.cs

@@ -347,12 +347,32 @@ public void ParallelWorldState_bal_validation_rejects_surplus_pre_execution_syst
         BlockAccessList suggestedBlockAccessList = new();
         suggestedBlockAccessList.AddAccountRead(Address.SystemUser);
         stateProvider.LoadSuggestedBlockAccessList(suggestedBlockAccessList, 10_000);
+        Block block = Build.A.Block.WithNumber(1).TestObject;
 
-        TestDelegate act = () => stateProvider.ValidateBlockAccessList(Build.A.BlockHeader.TestObject, 0, 10_000);
+        Assert.That(() => stateProvider.ValidateBlockAccessList(block.Header, 0, 10_000), Throws.Nothing);
 
+        TestDelegate act = () => stateProvider.SetBlockAccessList(block, Amsterdam.Instance);
         Assert.Throws<ParallelWorldState.InvalidBlockLevelAccessListException>(act);
     }
 
+    [Test, MaxTime(Timeout.MaxTestTime)]
+    public void ParallelWorldState_bal_validation_allows_system_account_changed_after_pre_execution()
+    {
+        ParallelWorldState stateProvider = new(TestWorldStateFactory.CreateForTest());
+        BlockAccessList suggestedBlockAccessList = new();
+        suggestedBlockAccessList.IncrementBlockAccessIndex();
+        suggestedBlockAccessList.AddBalanceChange(Address.SystemUser, 0, 1);
+        stateProvider.LoadSuggestedBlockAccessList(suggestedBlockAccessList, 10_000);
+        BlockHeader header = Build.A.BlockHeader.WithNumber(1).TestObject;
+
+        Assert.That(() => stateProvider.ValidateBlockAccessList(header, 0, 10_000), Throws.Nothing);
+
+        stateProvider.GeneratedBlockAccessList.IncrementBlockAccessIndex();
+        stateProvider.GeneratedBlockAccessList.AddBalanceChange(Address.SystemUser, 0, 1);
+
+        Assert.That(() => stateProvider.ValidateBlockAccessList(header, 1, 10_000), Throws.Nothing);
+    }
+
     [Test, MaxTime(Timeout.MaxTestTime)]
     public void ParallelWorldState_bal_validation_rejects_missing_explicit_system_account_read()
     {

src/Nethermind/Nethermind.State/ParallelWorldState.cs

@@ -320,10 +320,6 @@ void AdvanceSuggested()
             }
             else if (generatedHead is null)
             {
-                if (IsSystemAccountRead(suggestedHead.Value, index))
-                {
-                    throw new InvalidBlockLevelAccessListException(block, $"Suggested block-level access list contained surplus changes for {suggestedHead.Value.Address} at index {index}.");
-                }
                 if (HasNoChanges(suggestedHead.Value))
                 {
                     AdvanceSuggested();
@@ -346,10 +342,6 @@ void AdvanceSuggested()
             }
             else if (cmp > 0)
             {
-                if (IsSystemAccountRead(suggestedHead.Value, index))
-                {
-                    throw new InvalidBlockLevelAccessListException(block, $"Suggested block-level access list contained surplus changes for {suggestedHead.Value.Address} at index {index}.");
-                }
                 if (HasNoChanges(suggestedHead.Value))
                 {
                     AdvanceSuggested();
@@ -396,6 +388,7 @@ public void SetBlockAccessList(Block block, IReleaseSpec spec)
         }
         else
         {
+            ValidateSuggestedSystemAccountRead(block.Header);
             block.GeneratedBlockAccessList = GeneratedBlockAccessList;
             block.EncodedBlockAccessList = Rlp.Encode(GeneratedBlockAccessList).Bytes;
             block.Header.BlockAccessListHash = new(ValueKeccak.Compute(block.EncodedBlockAccessList).Bytes);
@@ -417,4 +410,23 @@ private static bool HasOptionalStorageReads(in ChangeAtIndex c)
 
     private static bool IsSystemAccountRead(in ChangeAtIndex c, ushort index)
         => index == 0 && c.Address == Address.SystemUser && HasNoChanges(c) && c.Reads == 0;
+
+    private void ValidateSuggestedSystemAccountRead(BlockHeader block)
+    {
+        if (_suggestedBlockAccessList?.GetAccountChanges(Address.SystemUser) is not { } suggestedSystemAccount ||
+            GeneratedBlockAccessList.GetAccountChanges(Address.SystemUser) is not null ||
+            !HasOnlyAccountRead(suggestedSystemAccount))
+        {
+            return;
+        }
+
+        throw new InvalidBlockLevelAccessListException(block, $"Suggested block-level access list contained surplus changes for {Address.SystemUser} at index 0.");
+    }
+
+    private static bool HasOnlyAccountRead(AccountChanges accountChanges)
+        => accountChanges.StorageChanges.Count == 0 &&
+           accountChanges.StorageReads.Count == 0 &&
+           accountChanges.BalanceChanges.Count == 0 &&
+           accountChanges.NonceChanges.Count == 0 &&
+           accountChanges.CodeChanges.Count == 0;
 }