From ac8d163fbbe2a9d9057d484f9b8d5302c1f43e77 Mon Sep 17 00:00:00 2001
From: Robin Salen <salenrobin@gmail.com>
Date: Fri, 4 Aug 2023 15:43:36 -0400
Subject: [PATCH] Prevent overflow

---
 evm/src/witness/operation.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/evm/src/witness/operation.rs b/evm/src/witness/operation.rs
index 16999a33bb..465e63b4a5 100644
--- a/evm/src/witness/operation.rs
+++ b/evm/src/witness/operation.rs
@@ -492,7 +492,11 @@ fn append_shift<F: Field>(
     }
 
     // Convert the shift, and log the corresponding arithmetic operation.
-    let input0 = U256::from(2).pow(input0);
+    let input0 = if input0 > U256::from(255u64) {
+        U256::zero()
+    } else {
+        U256::from(2).pow(input0)
+    };
     let operator = if row.op.shl.is_one() {
         BinaryOperator::Mul
     } else {