fix max call depth value calc

bin/node/runtime/src/lib.rs

@@ -1206,7 +1206,7 @@ impl pallet_contracts::Config for Runtime {
 	type CallFilter = Nothing;
 	type DepositPerItem = DepositPerItem;
 	type DepositPerByte = DepositPerByte;
-	type CallStack = [pallet_contracts::Frame<Self>; 6];
+	type CallStack = [pallet_contracts::Frame<Self>; 5];
 	type WeightPrice = pallet_transaction_payment::Pallet<Self>;
 	type WeightInfo = pallet_contracts::weights::SubstrateWeight<Self>;
 	type ChainExtension = ();

frame/contracts/src/lib.rs

@@ -389,7 +389,10 @@ pub mod pallet {
 			const MAX_STACK_SIZE: u32 = 1024 * 1024;
 			// Heap limit is normally 16 mempages of 64kb each = 1Mb per contract
 			let max_heap_size = T::Schedule::get().limits.max_memory_size();
-			let max_call_depth = T::CallStack::size() as u32;
+			// Max call depth is CallStack::size() + 1
+			let max_call_depth = u32::try_from(T::CallStack::size().saturating_add(1))
+				.expect("CallStack size is too big");
+
 			// Check that given configured `MaxCodeLen`, runtime heap memory limit can't be broken.
 			//
 			// In worst case, the decoded wasm contract code would be `x16` times larger than the

frame/contracts/src/tests.rs

@@ -394,7 +394,7 @@ impl Config for Test {
 	type RuntimeEvent = RuntimeEvent;
 	type RuntimeCall = RuntimeCall;
 	type CallFilter = TestFilter;
-	type CallStack = [Frame<Self>; 6];
+	type CallStack = [Frame<Self>; 5];
 	type WeightPrice = Self;
 	type WeightInfo = ();
 	type ChainExtension =