From ac0ff044606a663eeb47ef60ed5506f842753084 Mon Sep 17 00:00:00 2001
From: Martin HS <martin@swende.se>
Date: Mon, 19 Feb 2024 16:29:59 +0100
Subject: [PATCH] core/vm, params: ensure order of forks, prevent overflow
 (#29023)

This PR fixes an overflow which can could happen if inconsistent blockchain rules were configured. Additionally, it tries to prevent such inconsistencies from occurring by making sure that merge cannot be enabled unless previous fork(s) are also enabled.
---
 core/vm/operations_acl.go   |  7 ++++++-
 internal/ethapi/api_test.go |  2 +-
 params/config.go            | 10 ++++++----
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/core/vm/operations_acl.go b/core/vm/operations_acl.go
index bca6d1e83..f420a2410 100644
--- a/core/vm/operations_acl.go
+++ b/core/vm/operations_acl.go
@@ -187,7 +187,12 @@ func makeCallVariantGasCallEIP2929(oldCalculator gasFunc) gasFunc {
 		// outside of this function, as part of the dynamic gas, and that will make it
 		// also become correctly reported to tracers.
 		contract.Gas += coldCost
-		return gas + coldCost, nil
+
+		var overflow bool
+		if gas, overflow = math.SafeAdd(gas, coldCost); overflow {
+			return 0, ErrGasUintOverflow
+		}
+		return gas, nil
 	}
 }
 
diff --git a/internal/ethapi/api_test.go b/internal/ethapi/api_test.go
index 8a2e367f4..a6f7405eb 100644
--- a/internal/ethapi/api_test.go
+++ b/internal/ethapi/api_test.go
@@ -1818,6 +1818,7 @@ func setupReceiptBackend(t *testing.T, genBlocks int) (*testBackend, []common.Ha
 			tx  *types.Transaction
 			err error
 		)
+		b.SetPoS()
 		switch i {
 		case 0:
 			// transfer 1000wei
@@ -1866,7 +1867,6 @@ func setupReceiptBackend(t *testing.T, genBlocks int) (*testBackend, []common.Ha
 			b.AddTx(tx)
 			txHashes[i] = tx.Hash()
 		}
-		b.SetPoS()
 	})
 	return backend, txHashes
 }
diff --git a/params/config.go b/params/config.go
index 2c80f4f6b..d6935ed70 100644
--- a/params/config.go
+++ b/params/config.go
@@ -910,6 +910,8 @@ func (c *ChainConfig) Rules(num *big.Int, isMerge bool, timestamp uint64) Rules
 	if chainID == nil {
 		chainID = new(big.Int)
 	}
+	// disallow setting Merge out of order
+	isMerge = isMerge && c.IsLondon(num)
 	return Rules{
 		ChainID:          new(big.Int).Set(chainID),
 		IsHomestead:      c.IsHomestead(num),
@@ -923,9 +925,9 @@ func (c *ChainConfig) Rules(num *big.Int, isMerge bool, timestamp uint64) Rules
 		IsBerlin:         c.IsBerlin(num),
 		IsLondon:         c.IsLondon(num),
 		IsMerge:          isMerge,
-		IsShanghai:       c.IsShanghai(num, timestamp),
-		IsCancun:         c.IsCancun(num, timestamp),
-		IsPrague:         c.IsPrague(num, timestamp),
-		IsVerkle:         c.IsVerkle(num, timestamp),
+		IsShanghai:       isMerge && c.IsShanghai(num, timestamp),
+		IsCancun:         isMerge && c.IsCancun(num, timestamp),
+		IsPrague:         isMerge && c.IsPrague(num, timestamp),
+		IsVerkle:         isMerge && c.IsVerkle(num, timestamp),
 	}
 }