From 3718d0d47970c2ebe50df1ce1a46f042c44b0f86 Mon Sep 17 00:00:00 2001
From: marta-lokhova <marta@stellar.org>
Date: Wed, 31 Jul 2024 14:29:41 -0700
Subject: [PATCH] Harden handling of tx size upgrades in herder and add tests

---
 src/herder/HerderImpl.cpp       |  6 +++---
 src/herder/test/HerderTests.cpp | 21 +++++++++++++++++++--
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/src/herder/HerderImpl.cpp b/src/herder/HerderImpl.cpp
index 559f663e95..f437142331 100644
--- a/src/herder/HerderImpl.cpp
+++ b/src/herder/HerderImpl.cpp
@@ -355,9 +355,6 @@ HerderImpl::processExternalized(uint64 slotIndex, StellarValue const& value,
     }
 
     mLedgerManager.valueExternalized(ledgerData);
-
-    // Ensure potential upgrades are handled in overlay
-    maybeHandleUpgrade();
 }
 
 void
@@ -1099,6 +1096,9 @@ HerderImpl::lastClosedLedgerIncreased(bool latest)
     maybeSetupSorobanQueue(
         mLedgerManager.getLastClosedLedgerHeader().header.ledgerVersion);
 
+    // Ensure potential upgrades are handled in overlay
+    maybeHandleUpgrade();
+
     if (latest)
     {
         releaseAssert(isTracking());
diff --git a/src/herder/test/HerderTests.cpp b/src/herder/test/HerderTests.cpp
index cd90618d08..94612051f3 100644
--- a/src/herder/test/HerderTests.cpp
+++ b/src/herder/test/HerderTests.cpp
@@ -3797,8 +3797,10 @@ setupUpgradeAtNextLedger(Application& app)
         ConfigUpgradeSetFrameConstPtr configUpgradeSet;
         ConfigUpgradeSet configUpgradeSetXdr;
         auto& configEntry = configUpgradeSetXdr.updatedEntry.emplace_back();
-        configEntry.configSettingID(CONFIG_SETTING_CONTRACT_HISTORICAL_DATA_V0);
-        configEntry.contractHistoricalData().feeHistorical1KB = 1234;
+        configEntry.configSettingID(CONFIG_SETTING_CONTRACT_BANDWIDTH_V0);
+        configEntry.contractBandwidth().ledgerMaxTxsSizeBytes = 1'000'000;
+        configEntry.contractBandwidth().txMaxSizeBytes = 500'000;
+
         configUpgradeSet = makeConfigUpgradeSet(ltx, configUpgradeSetXdr);
 
         scheduledUpgrades.mConfigUpgradeSetKey = configUpgradeSet->getKey();
@@ -4016,6 +4018,14 @@ herderExternalizesValuesWithProtocol(uint32_t version)
         // Ensure C processes future tx set and its fees correctly (even though
         // its own ledger state isn't upgraded yet)
         receiveLedger(fourth, herderC);
+        if (protocolVersionStartsFrom(version, SOROBAN_PROTOCOL_VERSION))
+        {
+            REQUIRE(herderA.getMaxTxSize() ==
+                    500'000 + herderA.getFlowControlExtraBuffer());
+            REQUIRE(herderB.getMaxTxSize() ==
+                    500'000 + herderB.getFlowControlExtraBuffer());
+            REQUIRE(herderC.getMaxTxSize() < herderA.getMaxTxSize());
+        }
 
         // Wait until C goes out of sync, and processes future slots
         simulation->crankUntil([&]() { return !lmC.isSynced(); },
@@ -4074,6 +4084,13 @@ herderExternalizesValuesWithProtocol(uint32_t version)
         auto lcl = lmC.getLastClosedLedgerNum();
         REQUIRE(lcl == herderC.trackingConsensusLedgerIndex());
 
+        // C properly upgraded max tx size despite externalizing out-of-order
+        if (protocolVersionStartsFrom(version, SOROBAN_PROTOCOL_VERSION))
+        {
+            REQUIRE(herderC.getMaxTxSize() ==
+                    500'000 + herderC.getFlowControlExtraBuffer());
+        }
+
         // Ensure that C sent out a nomination message for the next consensus
         // round
         simulation->crankUntil(