core: remove stray account creations in state transition (#16470)

The 'from' and 'to' methods on StateTransitions are reader methods and
shouldn't have inadvertent side effects on state.

It is safe to remove the check in 'from' because account existence is
implicitly checked by the nonce and balance checks. If the account has
non-zero balance or nonce, it must exist. Even if the sender account has
nonce zero at the start of the state transition or no balance, the nonce
is incremented before execution and the account will be created at that
time.

It is safe to remove the check in 'to' because the EVM creates the
account if necessary.

Fixes #15119
This commit is contained in:
Felix Lange 2018-04-10 15:33:25 +02:00 committed by GitHub
parent 30deb6067f
commit 3caf16b15f
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 16 additions and 43 deletions

View File

@ -132,28 +132,12 @@ func ApplyMessage(evm *vm.EVM, msg Message, gp *GasPool) ([]byte, uint64, bool,
return NewStateTransition(evm, msg, gp).TransitionDb()
}
func (st *StateTransition) from() vm.AccountRef {
f := st.msg.From()
if !st.state.Exist(f) {
st.state.CreateAccount(f)
// to returns the recipient of the message.
func (st *StateTransition) to() common.Address {
if st.msg == nil || st.msg.To() == nil /* contract creation */ {
return common.Address{}
}
return vm.AccountRef(f)
}
func (st *StateTransition) to() vm.AccountRef {
if st.msg == nil {
return vm.AccountRef{}
}
to := st.msg.To()
if to == nil {
return vm.AccountRef{} // contract creation
}
reference := vm.AccountRef(*to)
if !st.state.Exist(*to) {
st.state.CreateAccount(*to)
}
return reference
return *st.msg.To()
}
func (st *StateTransition) useGas(amount uint64) error {
@ -166,12 +150,8 @@ func (st *StateTransition) useGas(amount uint64) error {
}
func (st *StateTransition) buyGas() error {
var (
state = st.state
sender = st.from()
)
mgval := new(big.Int).Mul(new(big.Int).SetUint64(st.msg.Gas()), st.gasPrice)
if state.GetBalance(sender.Address()).Cmp(mgval) < 0 {
if st.state.GetBalance(st.msg.From()).Cmp(mgval) < 0 {
return errInsufficientBalanceForGas
}
if err := st.gp.SubGas(st.msg.Gas()); err != nil {
@ -180,20 +160,17 @@ func (st *StateTransition) buyGas() error {
st.gas += st.msg.Gas()
st.initialGas = st.msg.Gas()
state.SubBalance(sender.Address(), mgval)
st.state.SubBalance(st.msg.From(), mgval)
return nil
}
func (st *StateTransition) preCheck() error {
msg := st.msg
sender := st.from()
// Make sure this transaction's nonce is correct
if msg.CheckNonce() {
nonce := st.state.GetNonce(sender.Address())
if nonce < msg.Nonce() {
// Make sure this transaction's nonce is correct.
if st.msg.CheckNonce() {
nonce := st.state.GetNonce(st.msg.From())
if nonce < st.msg.Nonce() {
return ErrNonceTooHigh
} else if nonce > msg.Nonce() {
} else if nonce > st.msg.Nonce() {
return ErrNonceTooLow
}
}
@ -208,8 +185,7 @@ func (st *StateTransition) TransitionDb() (ret []byte, usedGas uint64, failed bo
return
}
msg := st.msg
sender := st.from() // err checked in preCheck
sender := vm.AccountRef(msg.From())
homestead := st.evm.ChainConfig().IsHomestead(st.evm.BlockNumber)
contractCreation := msg.To() == nil
@ -233,8 +209,8 @@ func (st *StateTransition) TransitionDb() (ret []byte, usedGas uint64, failed bo
ret, _, st.gas, vmerr = evm.Create(sender, st.data, st.gas, st.value)
} else {
// Increment the nonce for the next transaction
st.state.SetNonce(sender.Address(), st.state.GetNonce(sender.Address())+1)
ret, st.gas, vmerr = evm.Call(sender, st.to().Address(), st.data, st.gas, st.value)
st.state.SetNonce(msg.From(), st.state.GetNonce(sender.Address())+1)
ret, st.gas, vmerr = evm.Call(sender, st.to(), st.data, st.gas, st.value)
}
if vmerr != nil {
log.Debug("VM returned with error", "err", vmerr)
@ -260,10 +236,8 @@ func (st *StateTransition) refundGas() {
st.gas += refund
// Return ETH for remaining gas, exchanged at the original rate.
sender := st.from()
remaining := new(big.Int).Mul(new(big.Int).SetUint64(st.gas), st.gasPrice)
st.state.AddBalance(sender.Address(), remaining)
st.state.AddBalance(st.msg.From(), remaining)
// Also return remaining gas to the block gas counter so it is
// available for the next transaction.

View File

@ -37,7 +37,6 @@ func TestState(t *testing.T) {
// Expected failures:
st.fails(`^stRevertTest/RevertPrecompiledTouch\.json/EIP158`, "bug in test")
st.fails(`^stRevertTest/RevertPrecompiledTouch\.json/Byzantium`, "bug in test")
st.fails(`^stRandom2/randomStatetest64[45]\.json/(EIP150|Frontier|Homestead)/.*`, "known bug #15119")
st.walk(t, stateTestDir, func(t *testing.T, name string, test *StateTest) {
for _, subtest := range test.Subtests() {