From ef66a1cc0eee294fbe73ae8734672d69c926d501 Mon Sep 17 00:00:00 2001
From: Ed Hennis <ed@ripple.com>
Date: Wed, 12 Nov 2025 13:46:11 -0500
Subject: [PATCH] Disable inner Batch transactions for Vault and Loan types

---
 src/test/app/Batch_test.cpp       | 21 ++++++++++++++++-----
 src/test/app/Loan_test.cpp        |  9 ++++++++-
 src/xrpld/app/tx/detail/Batch.cpp | 11 ++++++++++-
 src/xrpld/app/tx/detail/Batch.h   | 18 ++++++++++++++++++
 4 files changed, 52 insertions(+), 7 deletions(-)

diff --git a/src/test/app/Batch_test.cpp b/src/test/app/Batch_test.cpp
index b74d492cc1..2f3b9337e0 100644
--- a/src/test/app/Batch_test.cpp
+++ b/src/test/app/Batch_test.cpp
@@ -2543,6 +2543,11 @@ class Batch_test : public beast::unit_test::suite
     {
         testcase("loan");
 
+        bool const lendingBatchEnabled = !std::any_of(
+            Batch::disabledTxTypes.begin(),
+            Batch::disabledTxTypes.end(),
+            [](auto const& disabled) { return disabled == ttLOAN_BROKER_SET; });
+
         using namespace test::jtx;
 
         test::jtx::Env env{
@@ -2609,7 +2614,8 @@ class Batch_test : public beast::unit_test::suite
             {
                 auto const [txIDs, batchID] = submitBatch(
                     env,
-                    temBAD_SIGNATURE,
+                    lendingBatchEnabled ? temBAD_SIGNATURE
+                                        : temINVALID_INNER_BATCH,
                     batch::outer(lender, lenderSeq, batchFee, tfAllOrNothing),
                     batch::inner(
                         env.json(
@@ -2648,7 +2654,8 @@ class Batch_test : public beast::unit_test::suite
             {
                 auto const [txIDs, batchID] = submitBatch(
                     env,
-                    temBAD_SIGNER,
+                    lendingBatchEnabled ? temBAD_SIGNER
+                                        : temINVALID_INNER_BATCH,
                     batch::outer(lender, lenderSeq, batchFee, tfAllOrNothing),
                     batch::inner(
                         env.json(
@@ -2672,7 +2679,8 @@ class Batch_test : public beast::unit_test::suite
                 auto const batchFee = batch::calcBatchFee(env, 1, 2);
                 auto const [txIDs, batchID] = submitBatch(
                     env,
-                    tesSUCCESS,
+                    lendingBatchEnabled ? TER(tesSUCCESS)
+                                        : TER(temINVALID_INNER_BATCH),
                     batch::outer(lender, lenderSeq, batchFee, tfAllOrNothing),
                     batch::inner(
                         env.json(
@@ -2704,7 +2712,8 @@ class Batch_test : public beast::unit_test::suite
                 auto const batchFee = batch::calcBatchFee(env, 1, 2);
                 auto const [txIDs, batchID] = submitBatch(
                     env,
-                    tesSUCCESS,
+                    lendingBatchEnabled ? TER(tesSUCCESS)
+                                        : TER(temINVALID_INNER_BATCH),
                     batch::outer(lender, lenderSeq, batchFee, tfAllOrNothing),
                     batch::inner(
                         env.json(
@@ -2721,7 +2730,9 @@ class Batch_test : public beast::unit_test::suite
             }
             env.close();
             BEAST_EXPECT(env.le(brokerKeylet));
-            if (auto const sleLoan = env.le(loanKeylet); BEAST_EXPECT(sleLoan))
+            if (auto const sleLoan = env.le(loanKeylet); lendingBatchEnabled
+                    ? BEAST_EXPECT(sleLoan)
+                    : !BEAST_EXPECT(!sleLoan))
             {
                 BEAST_EXPECT(sleLoan->isFlag(lsfLoanImpaired));
             }
diff --git a/src/test/app/Loan_test.cpp b/src/test/app/Loan_test.cpp
index 47b76d2a8a..da8b964c94 100644
--- a/src/test/app/Loan_test.cpp
+++ b/src/test/app/Loan_test.cpp
@@ -5,6 +5,7 @@
 
 #include <xrpld/app/misc/LendingHelpers.h>
 #include <xrpld/app/misc/LoadFeeTrack.h>
+#include <xrpld/app/tx/detail/Batch.h>
 #include <xrpld/app/tx/detail/LoanSet.h>
 
 #include <xrpl/beast/xor_shift_engine.h>
@@ -3801,6 +3802,11 @@ protected:
         // From FIND-001
         testcase << "Batch Bypass Counterparty";
 
+        bool const lendingBatchEnabled = !std::any_of(
+            Batch::disabledTxTypes.begin(),
+            Batch::disabledTxTypes.end(),
+            [](auto const& disabled) { return disabled == ttLOAN_BROKER_SET; });
+
         using namespace jtx;
         using namespace std::chrono_literals;
         Env env(*this, all);
@@ -3846,7 +3852,8 @@ protected:
         env(batch::outer(borrower, seq, batchFee, tfAllOrNothing),
             batch::inner(forgedLoanSet, seq + 1),
             batch::inner(pay(borrower, lender, XRP(1)), seq + 2),
-            ter(temBAD_SIGNATURE));
+            ter(lendingBatchEnabled ? temBAD_SIGNATURE
+                                    : temINVALID_INNER_BATCH));
         env.close();
 
         // ? Check that the loan was NOT created
diff --git a/src/xrpld/app/tx/detail/Batch.cpp b/src/xrpld/app/tx/detail/Batch.cpp
index 052e90e19e..9d2fe4e47d 100644
--- a/src/xrpld/app/tx/detail/Batch.cpp
+++ b/src/xrpld/app/tx/detail/Batch.cpp
@@ -263,7 +263,8 @@ Batch::preflight(PreflightContext const& ctx)
             return temREDUNDANT;
         }
 
-        if (stx.getFieldU16(sfTransactionType) == ttBATCH)
+        auto const txType = stx.getFieldU16(sfTransactionType);
+        if (txType == ttBATCH)
         {
             JLOG(ctx.j.debug()) << "BatchTrace[" << parentBatchId << "]: "
                                 << "batch cannot have an inner batch txn. "
@@ -271,6 +272,14 @@ Batch::preflight(PreflightContext const& ctx)
             return temINVALID;
         }
 
+        if (std::any_of(
+                disabledTxTypes.begin(),
+                disabledTxTypes.end(),
+                [txType](auto const& disabled) { return txType == disabled; }))
+        {
+            return temINVALID_INNER_BATCH;
+        }
+
         if (!(stx.getFlags() & tfInnerBatchTxn))
         {
             JLOG(ctx.j.debug())
diff --git a/src/xrpld/app/tx/detail/Batch.h b/src/xrpld/app/tx/detail/Batch.h
index 1b1d7614d5..7889e91bdc 100644
--- a/src/xrpld/app/tx/detail/Batch.h
+++ b/src/xrpld/app/tx/detail/Batch.h
@@ -35,6 +35,24 @@ public:
 
     TER
     doApply() override;
+
+    static constexpr auto disabledTxTypes = std::to_array<TxType>({
+        ttVAULT_CREATE,
+        ttVAULT_SET,
+        ttVAULT_DELETE,
+        ttVAULT_DEPOSIT,
+        ttVAULT_WITHDRAW,
+        ttVAULT_CLAWBACK,
+        ttLOAN_BROKER_SET,
+        ttLOAN_BROKER_DELETE,
+        ttLOAN_BROKER_COVER_DEPOSIT,
+        ttLOAN_BROKER_COVER_WITHDRAW,
+        ttLOAN_BROKER_COVER_CLAWBACK,
+        ttLOAN_SET,
+        ttLOAN_DELETE,
+        ttLOAN_MANAGE,
+        ttLOAN_PAY,
+    });
 };
 
 }  // namespace ripple