wallet2: reject non-monotonic rct output distributions

src/wallet/wallet2.cpp

@@ -9047,6 +9047,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       // check we're clear enough of rct start, to avoid corner cases below
       THROW_WALLET_EXCEPTION_IF(rct_offsets.size() < std::max<size_t>(1, CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE),
           error::get_output_distribution, "Not enough rct outputs");
+      THROW_WALLET_EXCEPTION_IF(!std::is_sorted(rct_offsets.begin(), rct_offsets.end()),
+          error::get_output_distribution, "Daemon reports non-monotonic rct output distribution");
       THROW_WALLET_EXCEPTION_IF(rct_offsets.back() <= max_rct_index,
           error::get_output_distribution, "Daemon reports suspicious number of rct outputs");
     }