Add max tx gas limit

config/config.go

@@ -779,6 +779,9 @@ type MempoolConfig struct {
 	// NOTE: the max size of a tx transmitted over the network is {max-tx-bytes}.
 	MaxTxBytes int `mapstructure:"max-tx-bytes"`
 
+	// Maximium gas of a single transaction
+	MaxTxGas int64 `mapstructure:"max-tx-gas"`
+
 	// Maximum size of a batch of transactions to send to a peer
 	// Including space needed by encoding (one varint per transaction).
 	// XXX: Unused due to https://github.com/tendermint/tendermint/issues/5796
@@ -830,6 +833,7 @@ func DefaultMempoolConfig() *MempoolConfig {
 		MaxTxsBytes:                  1024 * 1024 * 1024, // 1GB
 		CacheSize:                    10000,
 		MaxTxBytes:                   1024 * 1024, // 1MB
+		MaxTxGas:                     7000000,     // Block gas limit is 10m
 		TTLDuration:                  0 * time.Second,
 		TTLNumBlocks:                 0,
 		TxNotifyThreshold:            0,

internal/mempool/mempool.go

@@ -451,6 +451,11 @@ func (txmp *TxMempool) ReapMaxBytesMaxGas(maxBytes, maxGas int64) types.Txs {
 		if maxBytes > -1 && totalSize+size > maxBytes {
 			return false
 		}
+
+		if wtx.gasWanted >= txmp.config.MaxTxGas {
+			txmp.metrics.TxGasWantedTooHigh.Add(1)
+			return false
+		}
 		totalSize += size
 		gas := totalGas + wtx.gasWanted
 		if maxGas > -1 && gas > maxGas {

internal/mempool/metrics.go

@@ -27,6 +27,9 @@ type Metrics struct {
 	// Total current mempool uncommitted txs bytes
 	TotalTxsSizeBytes metrics.Gauge
 
+	// Number of txs rejected because of high gas wanted
+	TxGasWantedTooHigh metrics.Counter
+
 	// Number of failed transactions.
 	FailedTxs metrics.Counter