fix: Charge gas even when there are no entries in gaskv

CHANGELOG.md

@@ -118,6 +118,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### Bug Fixes
 
+* (store) [#10218](https://github.com/cosmos/cosmos-sdk/pull/10218) Charge gas even when there are no entries while seeking.
 * (x/genutil) [#10104](https://github.com/cosmos/cosmos-sdk/pull/10104) Ensure the `init` command reads the `--home` flag value correctly.
 * [\#9651](https://github.com/cosmos/cosmos-sdk/pull/9651) Change inconsistent limit of `0` to `MaxUint64` on InfiniteGasMeter and add GasRemaining func to GasMeter.
 * [\#9639](https://github.com/cosmos/cosmos-sdk/pull/9639) Check store keys length before accessing them by making sure that `key` is of length `m+1` (for `key[n:m]`)

store/gaskv/store.go

@@ -108,9 +108,7 @@ func (gs *Store) iterator(start, end []byte, ascending bool) types.Iterator {
 	}
 
 	gi := newGasIterator(gs.gasMeter, gs.gasConfig, parent)
-	if gi.Valid() {
-		gi.(*gasIterator).consumeSeekGas()
-	}
+	gi.(*gasIterator).consumeSeekGas()
 
 	return gi
 }
@@ -143,10 +141,7 @@ func (gi *gasIterator) Valid() bool {
 // in the iterator. It incurs a flat gas cost for seeking and a variable gas
 // cost based on the current value's length if the iterator is valid.
 func (gi *gasIterator) Next() {
-	if gi.Valid() {
-		gi.consumeSeekGas()
-	}
-
+	gi.consumeSeekGas()
 	gi.parent.Next()
 }
 
@@ -177,8 +172,10 @@ func (gi *gasIterator) Error() error {
 // consumeSeekGas consumes on each iteration step a flat gas cost and a variable gas cost
 // based on the current value's length.
 func (gi *gasIterator) consumeSeekGas() {
-	value := gi.Value()
+	if gi.Valid() {
+		value := gi.Value()
 
-	gi.gasMeter.ConsumeGas(gi.gasConfig.ReadCostPerByte*types.Gas(len(value)), types.GasValuePerByteDesc)
+		gi.gasMeter.ConsumeGas(gi.gasConfig.ReadCostPerByte*types.Gas(len(value)), types.GasValuePerByteDesc)
+	}
 	gi.gasMeter.ConsumeGas(gi.gasConfig.IterNextCostFlat, types.GasIterNextCostFlatDesc)
 }