From f672833abeaee8d172bffae3dd846c815caedb53 Mon Sep 17 00:00:00 2001
From: grandizzy <grandizzy.the.egg@gmail.com>
Date: Wed, 12 Jun 2024 19:37:27 +0300
Subject: [PATCH] fix(fuzz): strip metadata when push bytes collect

---
 crates/evm/fuzz/src/strategies/state.rs | 20 +++++++++++++++++---
 crates/forge/tests/it/fuzz.rs           |  2 +-
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/crates/evm/fuzz/src/strategies/state.rs b/crates/evm/fuzz/src/strategies/state.rs
index 39dd3a467949..2ab6b74f7e87 100644
--- a/crates/evm/fuzz/src/strategies/state.rs
+++ b/crates/evm/fuzz/src/strategies/state.rs
@@ -10,7 +10,7 @@ use parking_lot::{lock_api::RwLockReadGuard, RawRwLock, RwLock};
 use revm::{
     db::{CacheDB, DatabaseRef, DbAccount},
     interpreter::opcode,
-    primitives::AccountInfo,
+    primitives::{AccountInfo, Bytecode},
 };
 use std::{
     collections::{BTreeMap, HashMap},
@@ -245,12 +245,26 @@ impl FuzzDictionary {
             // Insert push bytes
             if let Some(code) = &account_info.code {
                 self.insert_address(*address);
-                self.collect_push_bytes(code.bytes_slice());
+                self.collect_push_bytes(code);
             }
         }
     }
 
-    fn collect_push_bytes(&mut self, code: &[u8]) {
+    fn collect_push_bytes(&mut self, code: &Bytecode) {
+        let mut code = code.original_byte_slice();
+        if code.is_empty() {
+            return;
+        }
+
+        // Remove metadata by looking up the last two bytes of original bytecode.
+        if code.len() > 2 {
+            let metadata_len = &code[code.len() - 2..];
+            let metadata_len = u16::from_be_bytes([metadata_len[0], metadata_len[1]]).into();
+            if code.len() > metadata_len {
+                code = &code[..code.len() - 2 - metadata_len];
+            }
+        }
+
         let mut i = 0;
         let len = code.len().min(PUSH_BYTE_ANALYSIS_LIMIT);
         while i < len {
diff --git a/crates/forge/tests/it/fuzz.rs b/crates/forge/tests/it/fuzz.rs
index 4f8a6d41272b..20c8657760a1 100644
--- a/crates/forge/tests/it/fuzz.rs
+++ b/crates/forge/tests/it/fuzz.rs
@@ -158,7 +158,7 @@ async fn test_persist_fuzz_failure() {
 async fn test_scrape_bytecode() {
     let filter = Filter::new(".*", ".*", ".*fuzz/FuzzScrapeBytecode.t.sol");
     let mut runner = TEST_DATA_DEFAULT.runner();
-    runner.test_options.fuzz.runs = 2000;
+    runner.test_options.fuzz.dictionary.dictionary_weight = 100;
     runner.test_options.fuzz.seed = Some(U256::from(6u32));
     let suite_result = runner.test_collect(&filter);