Merge branch 'develop' into ximinez/fix/validator-cache

* XRPLF/develop:
  chore: Remove empty Taker.h (6984)
  chore: Enable clang-tidy modernize checks (6975)
  ci: Upload clang-tidy git diff (6983)
  fix: Add rounding to Vault invariants (6217) (6955)

include/xrpl/ledger/helpers/NFTokenHelpers.h

@@ -20,6 +20,10 @@ removeTokenOffersWithLimit(
     Keylet const& directory,
     std::size_t maxDeletableOffers);
 
+/** Returns tesSUCCESS if NFToken has few enough offers that it can be burned */
+TER
+notTooManyOffers(ReadView const& view, uint256 const& nftokenID);
+
 /** Finds the specified token in the owner's token directory. */
 std::optional<STObject>
 findToken(ReadView const& view, AccountID const& owner, uint256 const& nftokenID);

src/libxrpl/ledger/helpers/LendingHelpers.cpp

@@ -1857,18 +1857,8 @@ loanMakePayment(
 
     // -------------------------------------------------------------
     // overpayment handling
-    //
-    // If the "fixSecurity3_1_3" amendment is enabled, truncate "amount",
-    // at the loan scale. If the raw value is used, the overpayment
-    // amount could be meaningless dust. Trying to process such a small
-    // amount will, at best, waste time when all the result values round
-    // to zero. At worst, it can cause logical errors with tiny amounts
-    // of interest that don't add up correctly.
-    auto const roundedAmount = view.rules().enabled(fixSecurity3_1_3)
-        ? roundToAsset(asset, amount, loanScale, Number::towards_zero)
-        : amount;
     if (paymentType == LoanPaymentType::overpayment && loan->isFlag(lsfLoanOverpayment) &&
-        paymentRemainingProxy > 0 && totalPaid < roundedAmount &&
+        paymentRemainingProxy > 0 && totalPaid < amount &&
         numPayments < loanMaximumPaymentsPerTransaction)
     {
         TenthBips32 const overpaymentInterestRate{loan->at(sfOverpaymentInterestRate)};
@@ -1877,7 +1867,7 @@ loanMakePayment(
         // It shouldn't be possible for the overpayment to be greater than
         // totalValueOutstanding, because that would have been processed as
         // another normal payment. But cap it just in case.
-        Number const overpayment = std::min(roundedAmount - totalPaid, *totalValueOutstandingProxy);
+        Number const overpayment = std::min(amount - totalPaid, *totalValueOutstandingProxy);
 
         detail::ExtendedPaymentComponents const overpaymentComponents =
             detail::computeOverpaymentComponents(

src/libxrpl/ledger/helpers/NFTokenHelpers.cpp

@@ -621,6 +621,33 @@ removeTokenOffersWithLimit(ApplyView& view, Keylet const& directory, std::size_t
     return deletedOffersCount;
 }
 
+TER
+notTooManyOffers(ReadView const& view, uint256 const& nftokenID)
+{
+    std::size_t totalOffers = 0;
+
+    {
+        Dir const buys(view, keylet::nft_buys(nftokenID));
+        for (auto iter = buys.begin(); iter != buys.end(); iter.next_page())
+        {
+            totalOffers += iter.page_size();
+            if (totalOffers > maxDeletableTokenOfferEntries)
+                return tefTOO_BIG;
+        }
+    }
+
+    {
+        Dir const sells(view, keylet::nft_sells(nftokenID));
+        for (auto iter = sells.begin(); iter != sells.end(); iter.next_page())
+        {
+            totalOffers += iter.page_size();
+            if (totalOffers > maxDeletableTokenOfferEntries)
+                return tefTOO_BIG;
+        }
+    }
+    return tesSUCCESS;
+}
+
 bool
 deleteTokenOffer(ApplyView& view, std::shared_ptr<SLE> const& offer)
 {

src/libxrpl/tx/transactors/lending/LoanPay.cpp

@@ -30,7 +30,6 @@
 #include <bit>
 #include <cstdint>
 #include <memory>
-#include <vector>
 
 namespace xrpl {
 
@@ -144,7 +143,6 @@ LoanPay::calculateBaseFee(ReadView const& view, STTx const& tx)
     Number const numPaymentEstimate = static_cast<std::int64_t>(amount / regularPayment);
 
     // Charge one base fee per paymentsPerFeeIncrement payments, rounding up.
-    // This set round is safe because there's a mode guard just above
     Number::setround(Number::upward);
     auto const feeIncrements = std::max(
         std::int64_t(1),
@@ -442,10 +440,9 @@ LoanPay::doApply()
     // Vault object state changes
     view.update(vaultSle);
 
-    Number const assetsAvailableBefore = *assetsAvailableProxy;
-    Number const assetsTotalBefore = *assetsTotalProxy;
 #if !NDEBUG
     {
+        Number const assetsAvailableBefore = *assetsAvailableProxy;
         Number const pseudoAccountBalanceBefore = accountHolds(
             view,
             vaultPseudoAccount,
@@ -469,6 +466,16 @@ LoanPay::doApply()
         "xrpl::LoanPay::doApply",
         "assets available must not be greater than assets outstanding");
 
+    if (*assetsAvailableProxy > *assetsTotalProxy)
+    {
+        // LCOV_EXCL_START
+        JLOG(j_.fatal()) << "Vault assets available must not be greater "
+                            "than assets outstanding. Available: "
+                         << *assetsAvailableProxy << ", Total: " << *assetsTotalProxy;
+        return tecINTERNAL;
+        // LCOV_EXCL_STOP
+    }
+
     JLOG(j_.debug()) << "total paid to vault raw: " << totalPaidToVaultRaw
                      << ", total paid to vault rounded: " << totalPaidToVaultRounded
                      << ", total paid to broker: " << totalPaidToBroker
@@ -494,68 +501,12 @@ LoanPay::doApply()
     associateAsset(*vaultSle, asset);
 
     // Duplicate some checks after rounding
-    Number const assetsAvailableAfter = *assetsAvailableProxy;
-    Number const assetsTotalAfter = *assetsTotalProxy;
-
     XRPL_ASSERT_PARTS(
-        assetsAvailableAfter <= assetsTotalAfter,
+        *assetsAvailableProxy <= *assetsTotalProxy,
         "xrpl::LoanPay::doApply",
         "assets available must not be greater than assets outstanding");
-    if (assetsAvailableAfter == assetsAvailableBefore)
-    {
-        // An unchanged assetsAvailable indicates that the amount paid to the
-        // vault was zero, or rounded to zero. That should be impossible, but I
-        // can't rule it out for extreme edge cases, so fail gracefully if it
-        // happens.
-        //
-        // LCOV_EXCL_START
-        JLOG(j_.warn()) << "LoanPay: Vault assets available unchanged after rounding: "  //
-                        << "Before: " << assetsAvailableBefore                           //
-                        << ", After: " << assetsAvailableAfter;
-        return tecPRECISION_LOSS;
-        // LCOV_EXCL_STOP
-    }
-    if (paymentParts->valueChange != beast::zero && assetsTotalAfter == assetsTotalBefore)
-    {
-        // Non-zero valueChange with an unchanged assetsTotal indicates that the
-        // actual value change rounded to zero. That should be impossible, but I
-        // can't rule it out for extreme edge cases, so fail gracefully if it
-        // happens.
-        //
-        // LCOV_EXCL_START
-        JLOG(j_.warn())
-            << "LoanPay: Vault assets expected change, but unchanged after rounding: "  //
-            << "Before: " << assetsTotalBefore                                          //
-            << ", After: " << assetsTotalAfter                                          //
-            << ", ValueChange: " << paymentParts->valueChange;
-        return tecPRECISION_LOSS;
-        // LCOV_EXCL_STOP
-    }
-    if (paymentParts->valueChange == beast::zero && assetsTotalAfter != assetsTotalBefore)
-    {
-        // A change in assetsTotal when there was no valueChange indicates that
-        // something really weird happened. That should be flat out impossible.
-        //
-        // LCOV_EXCL_START
-        JLOG(j_.fatal()) << "LoanPay: Vault assets changed unexpectedly after rounding: "  //
-                         << "Before: " << assetsTotalBefore                                //
-                         << ", After: " << assetsTotalAfter                                //
-                         << ", ValueChange: " << paymentParts->valueChange;
-        return tecINTERNAL;
-        // LCOV_EXCL_STOP
-    }
-    if (assetsAvailableAfter > assetsTotalAfter)
-    {
-        // Assets available are not allowed to be larger than assets total.
-        // LCOV_EXCL_START
-        JLOG(j_.fatal()) << "LoanPay: Vault assets available must not be greater "
-                            "than assets outstanding. Available: "
-                         << assetsAvailableAfter << ", Total: " << assetsTotalAfter;
-        return tecINTERNAL;
-        // LCOV_EXCL_STOP
-    }
 
-    // These three values are used to check that funds are conserved after the transfers
+#if !NDEBUG
     auto const accountBalanceBefore = accountHolds(
         view,
         account_,
@@ -584,6 +535,7 @@ LoanPay::doApply()
               ahIGNORE_AUTH,
               j_,
               SpendableHandling::shFULL_BALANCE);
+#endif
 
     if (totalPaidToVaultRounded != beast::zero)
     {
@@ -619,22 +571,19 @@ LoanPay::doApply()
         return ter;
 
 #if !NDEBUG
-    {
-        Number const pseudoAccountBalanceAfter = accountHolds(
-            view,
-            vaultPseudoAccount,
-            asset,
-            FreezeHandling::fhIGNORE_FREEZE,
-            AuthHandling::ahIGNORE_AUTH,
-            j_);
-        XRPL_ASSERT_PARTS(
-            assetsAvailableAfter == pseudoAccountBalanceAfter,
-            "xrpl::LoanPay::doApply",
-            "vault pseudo balance agrees after");
-    }
-#endif
+    Number const assetsAvailableAfter = *assetsAvailableProxy;
+    Number const pseudoAccountBalanceAfter = accountHolds(
+        view,
+        vaultPseudoAccount,
+        asset,
+        FreezeHandling::fhIGNORE_FREEZE,
+        AuthHandling::ahIGNORE_AUTH,
+        j_);
+    XRPL_ASSERT_PARTS(
+        assetsAvailableAfter == pseudoAccountBalanceAfter,
+        "xrpl::LoanPay::doApply",
+        "vault pseudo balance agrees after");
 
-    // Check that funds are conserved
     auto const accountBalanceAfter = accountHolds(
         view,
         account_,
@@ -663,121 +612,14 @@ LoanPay::doApply()
               ahIGNORE_AUTH,
               j_,
               SpendableHandling::shFULL_BALANCE);
-    auto const balanceScale = [&]() {
-        // Find a reasonable scale to use for the balance comparisons.
-        //
-        // First find the minimum and maximum exponent of all the non-zero balances, before and
-        // after. If min and max are equal, use that value. If they are not, use "max + 1" to reduce
-        // rounding discrepancies without making the result meaningless. Cap the scale at
-        // STAmount::cMaxOffset, just in case the numbers are all very large.
-        std::vector<int> exponents;
 
-        for (auto const& a : {
-                 accountBalanceBefore,
-                 vaultBalanceBefore,
-                 brokerBalanceBefore,
-                 accountBalanceAfter,
-                 vaultBalanceAfter,
-                 brokerBalanceAfter,
-             })
-        {
-            // Exclude zeroes
-            if (a != beast::zero)
-                exponents.push_back(a.exponent());
-        }
-        if (exponents.empty())
-        {
-            UNREACHABLE("xrpl::LoanPay::doApply : all zeroes");
-            return 0;
-        }
-        auto const [minItr, maxItr] = std::ranges::minmax_element(exponents);
-        auto const min = *minItr;
-        auto const max = *maxItr;
-        JLOG(j_.trace()) << "Min scale: " << min << ", max scale: " << max;
-        // IOU rounding can be interesting. We want all the balance checks to agree, but don't want
-        // to round to such an extreme that it becomes meaningless.  e.g. Everything rounds to one
-        // digit. So add 1 to the max (reducing the number of digits after the decimal point by 1)
-        // if the scales are not already all the same.
-        return std::min(min == max ? max : max + 1, STAmount::cMaxOffset);
-    }();
-
-    // No object changes are made below this point
     XRPL_ASSERT_PARTS(
-        Number::getround() == Number::to_nearest,
-        "xrpl::LoanPay::doApply",
-        "Number rounding to_nearest");
-    NumberRoundModeGuard const mg(Number::to_nearest);
-
-    auto const accountBalanceBeforeRounded = roundToScale(accountBalanceBefore, balanceScale);
-    auto const vaultBalanceBeforeRounded = roundToScale(vaultBalanceBefore, balanceScale);
-    auto const brokerBalanceBeforeRounded = roundToScale(brokerBalanceBefore, balanceScale);
-
-    auto const totalBalanceBefore = accountBalanceBefore + vaultBalanceBefore + brokerBalanceBefore;
-    auto const totalBalanceBeforeRounded = roundToScale(totalBalanceBefore, balanceScale);
-
-    JLOG(j_.trace()) << "Before: "  //
-                     << "account " << Number(accountBalanceBeforeRounded) << " ("
-                     << Number(accountBalanceBefore) << ")"
-                     << ", vault " << Number(vaultBalanceBeforeRounded) << " ("
-                     << Number(vaultBalanceBefore) << ")"
-                     << ", broker " << Number(brokerBalanceBeforeRounded) << " ("
-                     << Number(brokerBalanceBefore) << ")"
-                     << ", total " << Number(totalBalanceBeforeRounded) << " ("
-                     << Number(totalBalanceBefore) << ")";
-
-    auto const accountBalanceAfterRounded = roundToScale(accountBalanceAfter, balanceScale);
-    auto const vaultBalanceAfterRounded = roundToScale(vaultBalanceAfter, balanceScale);
-    auto const brokerBalanceAfterRounded = roundToScale(brokerBalanceAfter, balanceScale);
-
-    auto const totalBalanceAfter = accountBalanceAfter + vaultBalanceAfter + brokerBalanceAfter;
-    auto const totalBalanceAfterRounded = roundToScale(totalBalanceAfter, balanceScale);
-
-    JLOG(j_.trace()) << "After: "  //
-                     << "account " << Number(accountBalanceAfterRounded) << " ("
-                     << Number(accountBalanceAfter) << ")"
-                     << ", vault " << Number(vaultBalanceAfterRounded) << " ("
-                     << Number(vaultBalanceAfter) << ")"
-                     << ", broker " << Number(brokerBalanceAfterRounded) << " ("
-                     << Number(brokerBalanceAfter) << ")"
-                     << ", total " << Number(totalBalanceAfterRounded) << " ("
-                     << Number(totalBalanceAfter) << ")";
-
-    auto const accountBalanceChange = accountBalanceAfter - accountBalanceBefore;
-    auto const vaultBalanceChange = vaultBalanceAfter - vaultBalanceBefore;
-    auto const brokerBalanceChange = brokerBalanceAfter - brokerBalanceBefore;
-
-    auto const totalBalanceChange = accountBalanceChange + vaultBalanceChange + brokerBalanceChange;
-    auto const totalBalanceChangeRounded = roundToScale(totalBalanceChange, balanceScale);
-
-    JLOG(j_.trace()) << "Changes: "                                    //
-                     << "account " << to_string(accountBalanceChange)  //
-                     << ", vault " << to_string(vaultBalanceChange)    //
-                     << ", broker " << to_string(brokerBalanceChange)  //
-                     << ", total " << to_string(totalBalanceChangeRounded) << " ("
-                     << Number(totalBalanceChange) << ")";
-
-    if (totalBalanceBeforeRounded != totalBalanceAfterRounded)
-    {
-        JLOG(j_.warn()) << "Total rounded balances don't match"
-                        << (totalBalanceChangeRounded == beast::zero ? ", but total changes do"
-                                                                     : "");
-    }
-    if (totalBalanceChangeRounded != beast::zero)
-    {
-        JLOG(j_.warn()) << "Total balance changes don't match"
-                        << (totalBalanceBeforeRounded == totalBalanceAfterRounded
-                                ? ", but total balances do"
-                                : "");
-    }
-
-    // Rounding for IOUs can be weird, so check a few different ways to show
-    // that funds are conserved.
-    XRPL_ASSERT_PARTS(
-        totalBalanceBeforeRounded == totalBalanceAfterRounded ||
-            totalBalanceChangeRounded == beast::zero,
+        accountBalanceBefore + vaultBalanceBefore + brokerBalanceBefore ==
+            accountBalanceAfter + vaultBalanceAfter + brokerBalanceAfter,
         "xrpl::LoanPay::doApply",
         "funds are conserved (with rounding)");
-
+    XRPL_ASSERT_PARTS(
+        accountBalanceAfter >= beast::zero, "xrpl::LoanPay::doApply", "positive account balance");
     XRPL_ASSERT_PARTS(
         accountBalanceAfter < accountBalanceBefore || account_ == asset.getIssuer(),
         "xrpl::LoanPay::doApply",
@@ -798,6 +640,7 @@ LoanPay::doApply()
         vaultBalanceAfter > vaultBalanceBefore || brokerBalanceAfter > brokerBalanceBefore,
         "xrpl::LoanPay::doApply",
         "vault and/or broker balance increased");
+#endif
 
     return tesSUCCESS;
 }

src/test/app/Loan_test.cpp

@@ -370,11 +370,16 @@ protected:
                         env.balance(vaultPseudo, broker.asset).number());
                     if (ownerCount == 0)
                     {
-                        // The Vault must be perfectly balanced if there
-                        // are no loans outstanding
+                        // Allow some slop for rounding IOUs
+
+                        // TODO: This needs to be an exact match once all the
+                        // other rounding issues are worked out.
                         auto const total = vaultSle->at(sfAssetsTotal);
                         auto const available = vaultSle->at(sfAssetsAvailable);
-                        env.test.BEAST_EXPECT(total == available);
+                        env.test.BEAST_EXPECT(
+                            total == available ||
+                            (!broker.asset.integral() && available != 0 &&
+                             ((total - available) / available < Number(1, -6))));
                         env.test.BEAST_EXPECT(vaultSle->at(sfLossUnrealized) == 0);
                     }
                 }
@@ -7063,140 +7068,6 @@ protected:
         BEAST_EXPECT(afterSecondCoverAvailable == 0);
     }
 
-    void
-    testYieldTheftRounding(std::uint32_t flags)
-    {
-        testcase("Rounding manipulation does not permit yield theft");
-        using namespace jtx;
-        using namespace loan;
-
-        // 1. Setup Environment
-        Env env(*this, all);
-        Account const issuer{"issuer"};
-        Account const lender{"lender"};
-        Account const borrower{"borrower"};
-
-        env.fund(XRP(1000), issuer, lender, borrower);
-        env.close();
-
-        // 2. Asset Selection
-        PrettyAsset const iou = issuer["USD"];
-        env(trust(lender, iou(100'000'000)));
-        env(trust(borrower, iou(100'000'000)));
-        env(pay(issuer, lender, iou(100'000'000)));
-        env(pay(issuer, borrower, iou(100'000'000)));
-        env.close();
-
-        // 3. Create Vault and Broker with High Debt Limit (100M)
-        auto const brokerInfo = createVaultAndBroker(
-            env,
-            iou,
-            lender,
-            {
-                .vaultDeposit = 5'000'000,
-                .debtMax = Number{100'000'000},
-                .coverDeposit = 500'000,
-            });
-        auto const [currentSeq, vaultKeylet] = [&]() {
-            auto const brokerSle = env.le(keylet::loanbroker(brokerInfo.brokerID));
-            auto const currentSeq = brokerSle->at(sfLoanSequence);
-            auto const vaultKeylet = keylet::vault(brokerSle->at(sfVaultID));
-            return std::make_tuple(currentSeq, vaultKeylet);
-        }();
-
-        // 4. Loan Parameters (Attack Vector)
-        Number const principal = 1'000'000;
-        TenthBips32 const interestRate = TenthBips32{1};  // 0.001%
-        std::uint32_t const paymentInterval = 86400;
-        std::uint32_t const paymentTotal = 3650;
-
-        auto const loanSetFee = fee(env.current()->fees().base * 2);
-        env(set(borrower, brokerInfo.brokerID, iou(principal).value(), flags),
-            sig(sfCounterpartySignature, lender),
-            loan::interestRate(interestRate),
-            loan::paymentInterval(paymentInterval),
-            loan::paymentTotal(paymentTotal),
-            fee(loanSetFee));
-        env.close();
-
-        // --- RETRIEVE OBJECTS & SETUP ATTACK ---
-
-        auto borrowerBalance = [&]() { return env.balance(borrower, iou); };
-        auto const borrowerScale = static_cast<STAmount const&>(borrowerBalance()).exponent();
-
-        auto const loanKeylet = keylet::loan(brokerInfo.brokerID, currentSeq);
-        auto const maybePeriodicPayment = [&]() -> std::optional<STAmount> {
-            auto const loanSle = env.le(loanKeylet);
-            if (!BEAST_EXPECT(loanSle))
-                return std::nullopt;
-            // Construct Payment
-            return STAmount{iou, loanSle->at(sfPeriodicPayment)};
-        }();
-        if (!maybePeriodicPayment)
-            return;
-        auto const periodicPayment = *maybePeriodicPayment;
-        auto const roundedPayment = roundToScale(periodicPayment, borrowerScale, Number::upward);
-
-        // ATTACK: Add dust buffer (1e-9) to force 'excess' logic execution
-        STAmount const paymentBuffer{iou, Number(1, -9)};
-        STAmount const attackPayment = periodicPayment + paymentBuffer;
-
-        auto const maybeInitialVaultAssets = [&]() -> std::optional<Number> {
-            auto const vault = env.le(vaultKeylet);
-            if (!BEAST_EXPECT(vault))
-                return std::nullopt;
-            return vault->at(sfAssetsTotal);
-        }();
-        if (!maybeInitialVaultAssets)
-            return;
-        auto const initialVaultAssets = *maybeInitialVaultAssets;
-
-        // 5. Execution Loop
-        int yieldTheftCount = 0;
-        auto previousAssetsTotal = initialVaultAssets;
-
-        for (int i = 0; i < 100; ++i)
-        {
-            auto const balanceBefore = borrowerBalance();
-            env(pay(borrower, loanKeylet.key, attackPayment, flags));
-            env.close();
-            auto const borrowerDelta = balanceBefore - borrowerBalance();
-            BEAST_EXPECT(borrowerDelta.signum() == roundedPayment.signum());
-
-            auto const loanSle = env.le(loanKeylet);
-            if (!BEAST_EXPECT(loanSle))
-                break;
-            auto const updatedPayment = STAmount{iou, loanSle->at(sfPeriodicPayment)};
-            BEAST_EXPECT(
-                (roundToScale(updatedPayment, borrowerScale, Number::upward) == roundedPayment));
-            BEAST_EXPECT(
-                (updatedPayment == periodicPayment) ||
-                (flags == tfLoanOverpayment && i >= 2 && updatedPayment < periodicPayment));
-
-            auto const currentVaultSle = env.le(vaultKeylet);
-            if (!BEAST_EXPECT(currentVaultSle))
-                break;
-
-            auto const currentAssetsTotal = currentVaultSle->at(sfAssetsTotal);
-            auto const delta = currentAssetsTotal - previousAssetsTotal;
-
-            BEAST_EXPECT(
-                (delta == beast::zero && borrowerDelta <= roundedPayment) ||
-                (delta > beast::zero && borrowerDelta > roundedPayment));
-
-            // If tx succeeded but Assets Total didn't change, interest was
-            // stolen.
-            if (delta == beast::zero && borrowerDelta > roundedPayment)
-            {
-                yieldTheftCount++;
-            }
-
-            previousAssetsTotal = currentAssetsTotal;
-        }
-
-        BEAST_EXPECTS(yieldTheftCount == 0, std::to_string(yieldTheftCount));
-    }
-
     // Tests that vault withdrawals work correctly when the vault has unrealized
     // loss from an impaired loan, ensuring the invariant check properly
     // accounts for the loss.
@@ -7335,11 +7206,6 @@ public:
         testLoanPayLateFullPaymentBypassesPenalties();
         testLoanCoverMinimumRoundingExploit();
 #endif
-        for (auto const flags : {0u, tfLoanOverpayment})
-        {
-            testYieldTheftRounding(flags);
-        }
-
         testWithdrawReflectsUnrealizedLoss();
         testInvalidLoanSet();
 

src/xrpld/app/misc/detail/ValidatorSite.cpp

@@ -161,7 +161,11 @@ ValidatorSite::load(
     {
         try
         {
-            sites_.emplace_back(uri);
+            // This is not super efficient, but it doesn't happen often.
+            bool found = std::ranges::any_of(
+                sites_, [&uri](auto const& site) { return site.loadedResource->uri == uri; });
+            if (!found)
+                sites_.emplace_back(uri);
         }
         catch (std::exception const& e)
         {
@@ -222,7 +226,17 @@ ValidatorSite::setTimer(
     std::lock_guard<std::mutex> const& site_lock,
     std::lock_guard<std::mutex> const& state_lock)
 {
-    auto next = std::ranges::min_element(
+    if (!sites_.empty() &&  //
+        std::ranges::all_of(
+            sites_, [](auto const& site) { return site.lastRefreshStatus.has_value(); }))
+    {
+        // If all of the sites have been handled at least once (including
+        // errors and timeouts), call missingSite, which will load the cache
+        // files for any lists that are still unavailable.
+        missingSite(site_lock);
+    }
+
+    auto const next = std::ranges::min_element(
         sites_, [](Site const& a, Site const& b) { return a.nextRefresh < b.nextRefresh; });
 
     if (next != sites_.end())
@@ -333,7 +347,7 @@ ValidatorSite::onRequestTimeout(std::size_t siteIdx, error_code const& ec)
         // processes a network error. Usually, this function runs first,
         // but on extremely rare occasions, the response handler can run
         // first, which will leave activeResource empty.
-        auto const& site = sites_[siteIdx];
+        auto& site = sites_[siteIdx];
         if (site.activeResource)
         {
             JLOG(j_.warn()) << "Request for " << site.activeResource->uri << " took too long";
@@ -341,6 +355,9 @@ ValidatorSite::onRequestTimeout(std::size_t siteIdx, error_code const& ec)
         else
             JLOG(j_.error()) << "Request took too long, but a response has "
                                 "already been processed";
+        if (!site.lastRefreshStatus)
+            site.lastRefreshStatus.emplace(
+                Site::Status{clock_type::now(), ListDisposition::invalid, "timeout"});
     }
 
     std::lock_guard const lock_state{state_mutex_};