fix(evm): replace hand-written transfer revert with a journaled KV buffer

plugin/dapp/evm/executor/attack_integration_test.go

@@ -82,9 +82,10 @@ func privKey(idx int) crypto.PrivKey { return util.TestPrivkeyList[idx] }
 
 func fundAddr(t *testing.T, exec *EVMExecutor, addr string, amount int64) {
 	t.Helper()
-	acc := exec.mStateDB.CoinsAccount.LoadAccount(addr)
+	// 写到执行器的 StateDB：mStateDB 的写缓冲每笔交易重建，写进去的余额不会留到下一次 Exec
+	acc := exec.GetCoinsAccount().LoadAccount(addr)
 	acc.Balance = amount
-	exec.mStateDB.CoinsAccount.SaveAccount(acc)
+	exec.GetCoinsAccount().SaveAccount(acc)
 }
 
 func addrFromRole(cfg *ctypes.Chain33Config, roleIdx int) string {

plugin/dapp/evm/executor/exec.go

@@ -58,7 +58,6 @@ func (evm *EVMExecutor) Exec(tx *types.Transaction, index int) (*types.Receipt,
 func (evm *EVMExecutor) innerExec(msg *common.Message, txHash []byte, sigType int32, index int, txFee uint64, readOnly bool) (receipt *types.Receipt, err error) {
 
 	cfg := evm.GetAPI().GetConfig()
-	evm.mStateDB.ResetRevertError()
 	// 获取当前区块的上下文信息构造EVM上下文
 	context := evm.NewEVMContext(msg, txHash)
 	execAddr := evm.getEvmExecAddress()
@@ -192,14 +191,6 @@ func (evm *EVMExecutor) innerExec(msg *common.Message, txHash []byte, sigType in
 		return receipt, vmerr
 	}
 
-	// A snapshot revert that failed leaves the account cache and the receipt describing
-	// different state, which chain33's checkKV can no longer validate. Fail the transaction
-	// (fee-only receipt, state rolled back by the framework) instead of committing it.
-	if rerr := evm.mStateDB.RevertError(); rerr != nil {
-		log.Error("innerExec snapshot revert failed", "error info", rerr)
-		return receipt, rerr
-	}
-
 	// 计算消耗了多少费用（实际消耗的费用）
 	usedFee, overflow := common.SafeMul(usedGas, uint64(msg.GasPrice()))
 	// 费用消耗溢出，执行失败

plugin/dapp/evm/executor/vm/runtime/blacklist_gap_test.go

@@ -89,8 +89,9 @@ func (e *gapEnv) fund(addr vmcommon.Address, amount int64) {
 	e.coins.SaveAccount(acc)
 }
 
+// balance 经由 mdb 读取：执行期间的转账只在 mdb 的写缓冲中，直接读 StateDB 看不到
 func (e *gapEnv) balance(addr vmcommon.Address) int64 {
-	return e.coins.LoadAccount(addr.String()).Balance
+	return e.mdb.CoinsAccount.LoadAccount(addr.String()).Balance
 }
 
 func (e *gapEnv) deploy(addr, creator vmcommon.Address, code []byte) {

plugin/dapp/evm/executor/vm/runtime/revert_mint_poc_test.go

@@ -0,0 +1,88 @@
+package runtime
+
+// 复现安全报告：回滚子调用的转账留在 coins 缓存里，被同一交易后续转账提交，造成增发。
+// 提交态 = 交易前状态 + 回执 KV（GetChangedData），与 execTxOne/ExecKVMemSet 一致。
+
+import (
+	"math/big"
+	"testing"
+
+	ctypes "github.com/33cn/chain33/types"
+	vmcommon "github.com/33cn/plugin/plugin/dapp/evm/executor/vm/common"
+	"github.com/stretchr/testify/require"
+)
+
+func zeroArgs4() []byte { return []byte{0x60, 0x00, 0x60, 0x00, 0x60, 0x00, 0x60, 0x00} }
+
+// Q：把收到的 value 原样 CALL 回 caller，然后 STOP。
+func buildRefundCode() []byte {
+	code := zeroArgs4()
+	return append(code, 0x34, 0x33, 0x5a, 0xf1, 0x00) // CALLVALUE CALLER GAS CALL STOP
+}
+
+// P：无 calldata 则 REVERT；有 calldata 则先把 value 转给 q，再把同额转给 payout。
+func buildTrapCode(q, payout vmcommon.Address) []byte {
+	code := []byte{0x36, 0x60, 0x09, 0x57, 0x60, 0x00, 0x60, 0x00, 0xfd, 0x5b}
+	code = append(code, zeroArgs4()...)
+	code = append(code, 0x34, 0x73)
+	code = append(code, q.Bytes()...)
+	code = append(code, 0x5a, 0xf1, 0x50)
+	code = append(code, zeroArgs4()...)
+	code = append(code, 0x34, 0x73)
+	code = append(code, payout.Bytes()...)
+	return append(code, 0x5a, 0xf1, 0x00)
+}
+
+func TestRevertedValueTransferMints(t *testing.T) {
+	env := newGapEnv(t, nil)
+	attacker, p, q, payout := addr(0xa1), addr(0xa2), addr(0xa3), addr(0xa4)
+	env.deploy(q, attacker, buildRefundCode())
+	env.deploy(p, attacker, buildTrapCode(q, payout))
+	const value = 100 * 1e8
+	env.fund(attacker, 1000*1e8)
+
+	addrs := []vmcommon.Address{attacker, p, q, payout}
+	committed := map[string]int64{}
+	var preSum int64
+	for _, a := range addrs {
+		committed[string(env.coins.AccountKey(a.String()))] = env.balance(a)
+		preSum += env.balance(a)
+	}
+
+	_, _, _, err := env.evm.Call(AccountRef(attacker), p, []byte{0x01}, 5_000_000, value)
+	require.NoError(t, err)
+
+	kvs, _ := env.mdb.GetChangedData(env.mdb.GetLastSnapshot().GetID())
+	for _, kv := range kvs {
+		if _, ok := committed[string(kv.Key)]; ok {
+			var acc ctypes.Account
+			require.NoError(t, ctypes.Decode(kv.Value, &acc))
+			committed[string(kv.Key)] = acc.Balance
+		}
+	}
+	var postSum int64
+	for _, a := range addrs {
+		b := committed[string(env.coins.AccountKey(a.String()))]
+		t.Logf("%s committed=%d cache=%d", a, b, env.balance(a))
+		postSum += b
+	}
+	require.Equal(t, preSum, postSum, "coin supply changed: minted %d", postSum-preSum)
+}
+
+// 同一帧内两次 SSTORE 同一槽位后 REVERT：Snapshot.revert 正序重放 prevalue，
+// 槽位停在第一次写入的值而不是原值，父帧能读到被回滚帧写过的数据。
+func TestRevertedDoubleSStoreLeaks(t *testing.T) {
+	env := newGapEnv(t, nil)
+	user, s := addr(0xb1), addr(0xb2)
+	code := []byte{0x36, 0x60, 0x19, 0x57, // 有 calldata 跳到内层
+		0x60, 0x00, 0x60, 0x00, 0x60, 0x01, 0x60, 0x00, 0x60, 0x00, 0x30, 0x5a, 0xf1, 0x50, // CALL self(1 字节 calldata)
+		0x60, 0x00, 0x54, 0x60, 0x01, 0x55, 0x00, // slot1 = slot0
+		0x5b, 0x60, 0x01, 0x60, 0x00, 0x55, 0x60, 0x02, 0x60, 0x00, 0x55, 0x60, 0x00, 0x60, 0x00, 0xfd} // slot0=1; slot0=2; REVERT
+	env.deploy(s, user, code)
+	_, _, _, err := env.evm.Call(AccountRef(user), s, nil, 5_000_000, 0)
+	require.NoError(t, err)
+	slot0 := env.mdb.GetState(s.String(), vmcommon.Hash{})
+	slot1 := env.mdb.GetState(s.String(), vmcommon.BigToHash(new(big.Int).SetInt64(1)))
+	t.Logf("slot0=%x slot1=%x", slot0.Big(), slot1.Big())
+	require.Equal(t, vmcommon.Hash{}, slot1, "parent frame observed a value written by a reverted frame")
+}

plugin/dapp/evm/executor/vm/state/journal_kv.go

@@ -0,0 +1,103 @@
+// Copyright Fuzamei Corp. 2018 All Rights Reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package state
+
+import (
+	"sort"
+
+	"github.com/33cn/chain33/common/db"
+	"github.com/33cn/chain33/types"
+)
+
+// journalKV 是 MemoryStateDB 与执行器 StateDB 之间的写缓冲，作用等同 chain33 的 txcache，
+// 但支持与 Snapshot 版本一一对应的嵌套回滚。
+//
+// EVM 执行期间所有经由 MemoryStateDB 的状态写入（coins/token 账户等）只进入本缓冲：
+// 回滚某个快照时，按 undo 日志倒序恢复写之前的值，调用方无需为每种写入单独实现 revert。
+// 执行成功后由 GetChangedData 把留下的写入一次性交给回执，并写回底层 StateDB。
+type journalKV struct {
+	parent db.KV
+	dirty  map[string][]byte // nil 值表示该 key 在本交易内不存在
+	undo   []kvUndo
+	marks  []int // marks[v] 为快照 v 创建时 undo 的长度
+}
+
+type kvUndo struct {
+	key     string
+	prev    []byte
+	hadPrev bool // 写之前 dirty 中是否已有该 key
+}
+
+func newJournalKV(parent db.KV) *journalKV {
+	return &journalKV{parent: parent, dirty: make(map[string][]byte)}
+}
+
+// Get 先读缓冲，再读底层 StateDB
+func (j *journalKV) Get(key []byte) ([]byte, error) {
+	if v, ok := j.dirty[string(key)]; ok {
+		if v == nil {
+			return nil, types.ErrNotFound
+		}
+		return v, nil
+	}
+	return j.parent.Get(key)
+}
+
+// Set 只写缓冲，并记录 undo
+func (j *journalKV) Set(key []byte, value []byte) error {
+	k := string(key)
+	prev, had := j.dirty[k]
+	j.undo = append(j.undo, kvUndo{key: k, prev: prev, hadPrev: had})
+	if value != nil {
+		value = append([]byte(nil), value...)
+	}
+	j.dirty[k] = value
+	return nil
+}
+
+// Begin/Commit/Rollback 满足 db.KV 接口；交易级的提交与回滚由执行器框架负责
+func (j *journalKV) Begin()        {}
+func (j *journalKV) Commit() error { return nil }
+func (j *journalKV) Rollback()     { j.revert(0) }
+
+// snapshot 记录快照 version 的回滚点，version 必须等于当前快照数
+func (j *journalKV) snapshot(version int) {
+	j.marks = append(j.marks[:version], len(j.undo))
+}
+
+// revertTo 把缓冲恢复到快照 version 创建时的状态
+func (j *journalKV) revertTo(version int) {
+	if version < 0 || version >= len(j.marks) {
+		return
+	}
+	j.revert(j.marks[version])
+	j.marks = j.marks[:version]
+}
+
+func (j *journalKV) revert(n int) {
+	for i := len(j.undo) - 1; i >= n; i-- {
+		u := j.undo[i]
+		if u.hadPrev {
+			j.dirty[u.key] = u.prev
+		} else {
+			delete(j.dirty, u.key)
+		}
+	}
+	j.undo = j.undo[:n]
+}
+
+// changes 返回缓冲中的全部写入，按 key 排序保证各节点一致
+func (j *journalKV) changes() []*types.KeyValue {
+	keys := make([]string, 0, len(j.dirty))
+	for k := range j.dirty {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	kvs := make([]*types.KeyValue, 0, len(keys))
+	for _, k := range keys {
+		kvs = append(kvs, &types.KeyValue{Key: []byte(k), Value: j.dirty[k]})
+	}
+	return kvs
+}