blockchain/vm: reject contract creation to non-empty storage root

blockchain/state/state_object.go

@@ -588,6 +588,13 @@ func (s *stateObject) Nonce() uint64 {
 	return s.account.GetNonce()
 }
 
+func (s *stateObject) Root() common.Hash {
+	if acc := account.GetProgramAccount(s.account); acc != nil {
+		return acc.GetStorageRoot().Unextend()
+	}
+	return common.Hash{}
+}
+
 // Never called, but must be present to allow stateObject to be used
 // as a vm.Account interface that also satisfies the vm.ContractRef
 // interface. Interfaces are awesome.

blockchain/state/statedb.go

@@ -291,6 +291,14 @@ func (s *StateDB) GetCode(addr common.Address) []byte {
 	return nil
 }
 
+func (s *StateDB) GetStorageRoot(addr common.Address) common.Hash {
+	stateObject := s.getStateObject(addr)
+	if stateObject != nil {
+		return stateObject.Root()
+	}
+	return common.Hash{}
+}
+
 func (s *StateDB) GetAccount(addr common.Address) account.Account {
 	stateObject := s.getStateObject(addr)
 	if stateObject != nil {

blockchain/vm/evm.go

@@ -511,16 +511,23 @@ func (evm *EVM) create(caller types.ContractRef, codeAndHash *codeAndHash, gas u
 		evm.StateDB.AddAddressToAccessList(address)
 	}
 
-	// Ensure there's no existing contract already at the designated address
+	// Ensure there's no existing contract already at the designated address.
+	// Account is regarded as existent if any of these three conditions is met:
+	// - the nonce is nonzero
+	// - the code is non-empty
+	// - the storage is non-empty
 	contractHash := evm.StateDB.ResolveCodeHash(address)
+	storageRoot := evm.StateDB.GetStorageRoot(address)
 
 	// The early Kaia design tried to support the account creation with a user selected address,
 	// so the account overwriting was restricted.
 	// Because the feature was postponed for a long time and the restriction can be abused to prevent SCA creation,
 	// Kaia enables SCA overwriting over EOA like Ethereum after Shanghai compatible hardfork.
 	// NOTE: The following code should be re-considered when Kaia enables TxTypeAccountCreation
 	if evm.chainRules.IsShanghai {
-		if evm.StateDB.GetNonce(address) != 0 || (contractHash != (common.Hash{}) && contractHash != emptyCodeHash) {
+		if evm.StateDB.GetNonce(address) != 0 ||
+			(contractHash != (common.Hash{}) && contractHash != types.EmptyCodeHash) || // non-empty code
+			(storageRoot != (common.Hash{}) && storageRoot != types.EmptyRootHash) { // non-empty storage
 			return nil, common.Address{}, 0, ErrContractAddressCollision
 		}
 	} else if evm.StateDB.Exist(address) {

blockchain/vm/interface.go

@@ -53,6 +53,7 @@ type StateDB interface {
 	SetCodeToEOA(common.Address, []byte, params.Rules) error
 	GetCodeSize(common.Address) int
 	GetVmVersion(common.Address) (params.VmVersion, bool)
+	GetStorageRoot(common.Address) common.Hash
 
 	ResolveCodeHash(common.Address) common.Hash
 	ResolveCode(common.Address) []byte