inactive amount can't exceed supply

Signed-off-by: Matteo Muraca <[email protected]>

substrate/frame/assets/src/impl_fungibles.rs

@@ -166,7 +166,10 @@ impl<T: Config<I>, I: 'static> fungibles::Unbalanced<T::AccountId> for Pallet<T,
 
 	fn deactivate(asset: Self::AssetId, amount: Self::Balance) {
 		Asset::<T, I>::mutate(&asset, |maybe_asset| match maybe_asset {
-			Some(ref mut asset) => asset.inactive.saturating_accrue(amount),
+			Some(ref mut asset) =>{
+				// Inactive amount can't exceed supply
+				asset.inactive = asset.inactive.saturating_add(amount).max(asset.supply);
+			},
 			None => log::error!("Called deactivate for nonexistent asset {:?}", asset),
 		});
 	}