Do not mark blocks as invalid unnecessarily (#15846)

beacon-chain/blockchain/error.go

@@ -30,7 +30,7 @@ var (
 	// errWSBlockNotFoundInEpoch is returned when a block is not found in the WS cache or DB within epoch.
 	errWSBlockNotFoundInEpoch = errors.New("weak subjectivity root not found in db within epoch")
 	// ErrNotDescendantOfFinalized is returned when a block is not a descendant of the finalized checkpoint
-	ErrNotDescendantOfFinalized = invalidBlock{error: errors.New("not descendant of finalized checkpoint")}
+	ErrNotDescendantOfFinalized = errors.New("not descendant of finalized checkpoint")
 	// ErrNotCheckpoint is returned when a given checkpoint is not a
 	// checkpoint in any chain known to forkchoice
 	ErrNotCheckpoint = errors.New("not a checkpoint in forkchoice")

beacon-chain/blockchain/receive_block.go

@@ -219,6 +219,9 @@ func (s *Service) validateExecutionAndConsensus(
 	eg.Go(func() error {
 		var err error
 		postState, err = s.validateStateTransition(ctx, preState, block)
+		if errors.Is(err, ErrNotDescendantOfFinalized) {
+			return invalidBlock{error: err, root: block.Root()}
+		}
 		if err != nil {
 			return errors.Wrap(err, "failed to validate consensus state transition function")
 		}

changelog/potuz_invalid_not_descendant.md

@@ -0,0 +1,3 @@
+### Fixed
+
+- Do not mark blocks as invalid from ErrNotDescendantOfFinalized