From 74e331f3e933747eeffd06f74d4861921cf0a65c Mon Sep 17 00:00:00 2001
From: Ed Hennis <ed@ripple.com>
Date: Thu, 6 Nov 2025 19:36:40 -0500
Subject: [PATCH] Handle zero rate in `computePaymentFactor`

---
 src/xrpld/app/misc/detail/LendingHelpers.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/xrpld/app/misc/detail/LendingHelpers.cpp b/src/xrpld/app/misc/detail/LendingHelpers.cpp
index f8ed477b9b..ad0e98b07e 100644
--- a/src/xrpld/app/misc/detail/LendingHelpers.cpp
+++ b/src/xrpld/app/misc/detail/LendingHelpers.cpp
@@ -73,6 +73,12 @@ computePaymentFactor(
     Number const& periodicRate,
     std::uint32_t paymentsRemaining)
 {
+    // periodicRate should never be zero in this function, but if it is,
+    // then 1/paymentRemaining is the most accurate factor that avoids
+    // divide by 0.
+    if (periodicRate == beast::zero)
+        return Number{1} / paymentsRemaining;
+
     /*
      * This formula is from the XLS-66 spec, section 3.2.4.1.1 (Regular
      * Payment), though "raisedRate" is computed only once and used twice.