From 527d7bbedeab29ba84b420937dbd462f5b6256fa Mon Sep 17 00:00:00 2001
From: tequ <git@tequ.dev>
Date: Fri, 30 Jan 2026 23:24:50 +0900
Subject: [PATCH] fix to return error if FeeAmount > Balance on SponsorshipSet

---
 src/test/app/Sponsor_test.cpp              | 18 ++++++++++++++++--
 src/xrpld/app/tx/detail/SponsorshipSet.cpp |  6 +++++-
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/test/app/Sponsor_test.cpp b/src/test/app/Sponsor_test.cpp
index 5e1bbea2dc..05923635c0 100644
--- a/src/test/app/Sponsor_test.cpp
+++ b/src/test/app/Sponsor_test.cpp
@@ -156,22 +156,36 @@ public:
 
         // Invalid Sponsee
         env(sponsor::set(sponsor, 0), sponsor::sponseeAcc(noFunded), ter(tecNO_DST));
+        env.close();
 
         // Invalid Sponsor
         env(sponsor::set(sponsor, tfDeleteObject), sponsor::sponsorAcc(noFunded), ter(tecNO_DST));
+        env.close();
 
         // Invalid Delete operation (sponsorship not found)
         env(sponsor::set(sponsor, tfDeleteObject), sponsor::sponseeAcc(alice), ter(tecNO_ENTRY));
+        env.close();
 
         // DisallowIncomingSponsor: tested in other testcase
 
         // insufficent reserve to create sponsorship
         adjustAccountXRPBalance(env, sponsor, reserve(env, 1) - drops(1));
         env(sponsor::set(sponsor, 0, 100, XRP(100)), sponsor::sponseeAcc(alice), ter(tecUNFUNDED));
+        env.close();
+
+        //  FeeAmount + Fee > Balance
+        /// Balance = 1000XRP, FeeAmount = 1001XRP
+        adjustAccountXRPBalance(env, sponsor, XRP(1000));
+        env(sponsor::set_fee(sponsor, 0, XRP(1001)), sponsor::sponseeAcc(alice), fee(XRP(1)), ter(tecUNFUNDED));
+        env.close();
+        /// Balance = 1000XRP, FeeAmount = 999XRP, Fee=2XRP
+        adjustAccountXRPBalance(env, sponsor, XRP(1000));
+        env(sponsor::set_fee(sponsor, 0, XRP(999)), sponsor::sponseeAcc(alice), fee(XRP(2)), ter(tecUNFUNDED));
+        env.close();
 
         // create sponsor to use above tests
-        adjustAccountXRPBalance(env, sponsor, reserve(env, 1));
-        env(sponsor::set(sponsor, 0, 100, XRP(100)), sponsor::sponseeAcc(alice), ter(tesSUCCESS));
+        adjustAccountXRPBalance(env, sponsor, XRP(1001));
+        env(sponsor::set(sponsor, 0, 100, XRP(1000)), sponsor::sponseeAcc(alice), fee(XRP(1)), ter(tesSUCCESS));
         env.close();
     }
 
diff --git a/src/xrpld/app/tx/detail/SponsorshipSet.cpp b/src/xrpld/app/tx/detail/SponsorshipSet.cpp
index 2c6e6f6e36..2ae7dda8d9 100644
--- a/src/xrpld/app/tx/detail/SponsorshipSet.cpp
+++ b/src/xrpld/app/tx/detail/SponsorshipSet.cpp
@@ -147,7 +147,8 @@ SponsorshipSet::preclaim(PreclaimContext const& ctx)
         return tecINTERNAL;  // LCOV_EXCL_LINE
 
     // check Sponsor
-    if (!ctx.view.exists(keylet::account(sponsor)))
+    auto const sponsorAccSle = ctx.view.read(keylet::account(sponsor));
+    if (!sponsorAccSle)
         return tecNO_DST;
 
     // check Sponsee
@@ -215,6 +216,9 @@ SponsorshipSet::doApply()
 
     auto reserveSponsorAccSle = getTxReserveSponsor(view(), ctx_.tx);
 
+    if (feeAmount && (*feeAmount).xrp() > (*sponsorAccSle)[sfBalance])
+        return tecUNFUNDED;
+
     if (!sponsorObjSle)
     {
         // Create