From 3a5cb6a441731a1217d7f8c8a97ea62ff8edc51c Mon Sep 17 00:00:00 2001
From: Navid Rahimi <rahimi.nv@gmail.com>
Date: Mon, 24 Aug 2026 12:14:37 +0000
Subject: [PATCH] LLMQ: Lock InstantSend input request IDs

---
 src/llmq/quorums_instantsend.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/llmq/quorums_instantsend.cpp b/src/llmq/quorums_instantsend.cpp
index 43383681f9..f3b7d3696e 100644
--- a/src/llmq/quorums_instantsend.cpp
+++ b/src/llmq/quorums_instantsend.cpp
@@ -467,7 +467,10 @@ bool CInstantSendManager::ProcessTx(const CTransaction& tx, bool allowReSigning,
     for (size_t i = 0; i < tx.vin.size(); i++) {
         auto& in = tx.vin[i];
         auto& id = ids[i];
-        inputRequestIds.emplace(id);
+        {
+            LOCK(cs);
+            inputRequestIds.emplace(id);
+        }
         LogPrint("instantsend", "CInstantSendManager::%s -- txid=%s: trying to vote on input %s with id %s. allowReSigning=%d\n", __func__,
                  tx.GetHash().ToString(), in.prevout.ToStringShort(), id.ToString(), allowReSigning);
         if (quorumSigningManager->AsyncSignIfMember(llmqType, id, tx.GetHash(), allowReSigning)) {