From e4476e58218a2b582676250caa0ce6dc380d2235 Mon Sep 17 00:00:00 2001
From: Mayukha Vadari <mvadari@gmail.com>
Date: Thu, 10 Sep 2026 18:03:20 -0400
Subject: [PATCH] fix: Carry the configured gas settings into the genesis
 ledger
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`FeeSetup::toFees()` returned the three-argument `Fees`, leaving `gasLimit`,
`bytecodeSizeLimit` and `gasPrice` at zero. `startGenesisLedger` passes that
straight into the genesis `Ledger`, which is where those three are written to
the `FeeSettings` entry — so a network started fresh with `featureSmartEscrow`
in its initial amendment set got a gas limit of zero, i.e. Smart Escrow
switched off no matter what the operator configured.

Carrying them through `toFees()` alone is not enough. Every `Ledger` built
from stored data is seeded with the same `Fees`, and `Ledger::setup()` only
overwrites the fields the `FeeSettings` entry actually carries. A ledger from
before the amendment carries none, so the seed would survive and the node
would read its own configuration back as though the network had agreed to it —
and then never vote for the values it wants, because `doValidation` only votes
when the current setting differs from the target.

So the genesis constructor now clears the three whenever it does not write
them. A ledger reports what its `FeeSettings` entry holds, and nothing more.

Reported by depthfirst-app and Copilot on #8214.
---
 src/libxrpl/ledger/Ledger.cpp | 10 +++++++
 src/test/app/FeeVote_test.cpp | 54 +++++++++++++++++++++++++++++++++++
 src/xrpld/core/Config.h       |  6 +++-
 3 files changed, 69 insertions(+), 1 deletion(-)

diff --git a/src/libxrpl/ledger/Ledger.cpp b/src/libxrpl/ledger/Ledger.cpp
index 86a22eba60..9f70e89f02 100644
--- a/src/libxrpl/ledger/Ledger.cpp
+++ b/src/libxrpl/ledger/Ledger.cpp
@@ -204,6 +204,16 @@ Ledger::Ledger(
             sle->at(sfBytecodeSizeLimit) = fees.bytecodeSizeLimit;
             sle->at(sfGasPrice) = fees.gasPrice;
         }
+        else
+        {
+            // This ledger does not carry the gas settings, so it must not
+            // report them either. Otherwise a node reads its own config back
+            // as though the network had agreed to it, and never votes for the
+            // values it wants.
+            fees_.gasLimit = 0;
+            fees_.bytecodeSizeLimit = 0;
+            fees_.gasPrice = 0;
+        }
         rawInsert(sle);
     }
 
diff --git a/src/test/app/FeeVote_test.cpp b/src/test/app/FeeVote_test.cpp
index 5136ef0c3b..8fd91683a1 100644
--- a/src/test/app/FeeVote_test.cpp
+++ b/src/test/app/FeeVote_test.cpp
@@ -935,6 +935,59 @@ class FeeVote_test : public beast::unit_test::Suite
             feeTx.getFieldAmount(sfReserveIncrementDrops) == XRPAmount{setup.ownerReserve});
     }
 
+    void
+    testGenesisFeeSettings()
+    {
+        testcase("genesis FeeSettings carries the configured gas settings");
+
+        using namespace jtx;
+
+        Env env(*this, testableAmendments());
+        auto const& cfg = env.app().config().fees;
+        BEAST_EXPECT(cfg.gasLimit != 0 && cfg.bytecodeSizeLimit != 0 && cfg.gasPrice != 0);
+
+        auto const genesisWith = [&](std::vector<uint256> const& amendments) {
+            return std::make_shared<Ledger>(
+                kCreateGenesis,
+                Rules{env.app().config().features},
+                cfg.toFees(),
+                amendments,
+                env.app().getNodeFamily());
+        };
+
+        {
+            // With the amendment, the operator's configuration becomes the
+            // network's starting point.
+            auto const ledger = genesisWith({featureSmartEscrow});
+            auto const sle = ledger->read(keylet::feeSettings());
+            if (BEAST_EXPECT(sle))
+            {
+                BEAST_EXPECT(sle->getFieldU32(sfGasLimit) == cfg.gasLimit);
+                BEAST_EXPECT(sle->getFieldU32(sfBytecodeSizeLimit) == cfg.bytecodeSizeLimit);
+                BEAST_EXPECT(sle->getFieldU32(sfGasPrice) == cfg.gasPrice);
+            }
+            BEAST_EXPECT(ledger->fees().gasLimit == cfg.gasLimit);
+            BEAST_EXPECT(ledger->fees().bytecodeSizeLimit == cfg.bytecodeSizeLimit);
+            BEAST_EXPECT(ledger->fees().gasPrice == cfg.gasPrice);
+        }
+
+        {
+            // Without it, the entry carries nothing and the ledger reports
+            // nothing, so the node still has something to vote for.
+            auto const ledger = genesisWith({});
+            auto const sle = ledger->read(keylet::feeSettings());
+            if (BEAST_EXPECT(sle))
+            {
+                BEAST_EXPECT(!sle->isFieldPresent(sfGasLimit));
+                BEAST_EXPECT(!sle->isFieldPresent(sfBytecodeSizeLimit));
+                BEAST_EXPECT(!sle->isFieldPresent(sfGasPrice));
+            }
+            BEAST_EXPECT(ledger->fees().gasLimit == 0);
+            BEAST_EXPECT(ledger->fees().bytecodeSizeLimit == 0);
+            BEAST_EXPECT(ledger->fees().gasPrice == 0);
+        }
+    }
+
     void
     testDoVotingSmartEscrow()
     {
@@ -1098,6 +1151,7 @@ class FeeVote_test : public beast::unit_test::Suite
         testSingleInvalidTransaction();
         testDoValidation();
         testDoVoting();
+        testGenesisFeeSettings();
         testDoVotingSmartEscrow();
     }
 };
diff --git a/src/xrpld/core/Config.h b/src/xrpld/core/Config.h
index 852a9d9f4b..01d0514b0e 100644
--- a/src/xrpld/core/Config.h
+++ b/src/xrpld/core/Config.h
@@ -90,7 +90,11 @@ struct FeeSetup
     [[nodiscard]] Fees
     toFees() const
     {
-        return Fees{referenceFee, accountReserve, ownerReserve};
+        Fees fees{referenceFee, accountReserve, ownerReserve};
+        fees.gasLimit = gasLimit;
+        fees.bytecodeSizeLimit = bytecodeSizeLimit;
+        fees.gasPrice = gasPrice;
+        return fees;
     }
 };