chill_other takes stash

substrate/frame/staking/src/benchmarking.rs

@@ -873,7 +873,7 @@ benchmarks! {
 		)?;
 
 		let caller = whitelisted_caller();
-	}: _(RawOrigin::Signed(caller), controller)
+	}: _(RawOrigin::Signed(caller), stash.clone())
 	verify {
 		assert!(!T::VoterList::contains(&stash));
 	}

substrate/frame/staking/src/pallet/mod.rs

@@ -1764,11 +1764,13 @@ pub mod pallet {
 		/// who do not satisfy these requirements.
 		#[pallet::call_index(23)]
 		#[pallet::weight(T::WeightInfo::chill_other())]
-		pub fn chill_other(origin: OriginFor<T>, controller: T::AccountId) -> DispatchResult {
+		pub fn chill_other(origin: OriginFor<T>, stash: T::AccountId) -> DispatchResult {
 			// Anyone can call this function.
 			let caller = ensure_signed(origin)?;
-			let ledger = Self::ledger(Controller(controller.clone()))?;
-			let stash = ledger.stash;
+			let ledger = Self::ledger(Stash(stash.clone()))?;
+			let controller = ledger.controller()
+				.defensive_proof("ledger was fetched used the StakingInterface, so controller field must exist; qed.")
+				.ok_or(Error::<T>::NotController)?;
 
 			// In order for one user to chill another user, the following conditions must be met:
 			//