Stop decoding instructions after finding an invalid opcode

NomicFoundation · Jan 10, 2025 · 9a022ba · 9a022ba
1 parent 00d9527
commit 9a022ba
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Showing 3 changed files with 9 additions and 3 deletions.
diff --git a/Cargo.lock b/Cargo.lock
diff --git a/crates/edr_solidity/Cargo.toml b/crates/edr_solidity/Cargo.toml
@@ -11,6 +11,7 @@ alloy-sol-types = { version = "0.7.4", default-features = false, features = ["st
 edr_eth = { version = "0.3.5", path = "../edr_eth" }
 edr_evm = { version = "0.3.5", path = "../edr_evm" }
 indexmap = { version = "2", features = ["serde"] }
+log = { version = "0.4.17", default-features = false }
 parking_lot = { version = "0.12.1", default-features = false }
 serde = { version = "1.0.158", default-features = false, features = ["std"] }
 serde_json = { version = "1.0.89", features = ["preserve_order"] }

diff --git a/crates/edr_solidity/src/source_map.rs b/crates/edr_solidity/src/source_map.rs
@@ -2,6 +2,7 @@
 use std::sync::Arc;
 
 use edr_evm::interpreter::OpCode;
+use log::debug;
 
 use crate::build_model::{BuildModel, Instruction, JumpType, SourceLocation};
 
@@ -159,9 +160,12 @@ pub fn decode_instructions(
         let source_map = &source_maps[instructions.len()];
 
         let pc = bytes_index;
-        let opcode = match OpCode::new(bytecode[pc]) {
-            Some(opcode) => opcode,
-            None => continue,
+        let opcode = if let Some(opcode) = OpCode::new(bytecode[pc]) { opcode } else {
+            debug!("Invalid opcode {} at pc: {}", bytecode[pc], pc);
+
+            // We assume this happens because the source maps point to the metadata region of the bytecode.
+            // That means that the actual instructions have already been decoded and we can stop here.
+            return instructions;
         };
 
         let push_data = if opcode.is_push() {