Charge for max length in LDC opcode (#776)

* Release v0.54.0

* Charge for max length in LDC opcode

* Updated CHANGELOG.md

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Changed
+- [#776](https://github.com/FuelLabs/fuel-vm/pull/776): Charge for max length in LDC opcode.
+
 ## [Version 0.54.0]
 
 ### Added

fuel-vm/src/interpreter/blockchain.rs

@@ -606,9 +606,6 @@ where
             return Err(PanicReason::ContractMaxSize.into())
         }
 
-        let new_sp = ssp.saturating_add(length);
-        self.memory.grow_stack(new_sp)?;
-
         self.input_contracts.check(&contract_id)?;
 
         // Fetch the storage contract
@@ -619,16 +616,20 @@ where
             profiler: self.profiler,
         };
         let contract_len = contract_size(&self.storage, &contract_id)?;
+        let charge_len = core::cmp::max(contract_len as u64, length);
         dependent_gas_charge_without_base(
             self.cgas,
             self.ggas,
             profiler,
             self.gas_cost,
-            contract_len as u64,
+            charge_len,
         )?;
         let contract = super::contract::contract(self.storage, &contract_id)?;
         let contract_bytes = contract.as_ref().as_ref();
 
+        let new_sp = ssp.saturating_add(length);
+        self.memory.grow_stack(new_sp)?;
+
         // Set up ownership registers for the copy using old ssp
         let owner =
             OwnershipRegisters::only_allow_stack_write(new_sp, *self.ssp, *self.hp);