From 9cdd72575773bb8eb4608563469d7731ffb78e3b Mon Sep 17 00:00:00 2001
From: Matthias Seitz <matthias.seitz@outlook.de>
Date: Wed, 22 Nov 2023 17:36:00 +0100
Subject: [PATCH 1/2] fix: safer stack

---
 crates/interpreter/src/interpreter/stack.rs | 31 +++++++++++++++++++--
 crates/revm/src/inspector/eip3155.rs        | 10 +++----
 2 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/crates/interpreter/src/interpreter/stack.rs b/crates/interpreter/src/interpreter/stack.rs
index f64b8a0f9f..7b82b5ceed 100644
--- a/crates/interpreter/src/interpreter/stack.rs
+++ b/crates/interpreter/src/interpreter/stack.rs
@@ -8,9 +8,9 @@ use core::fmt;
 /// EVM interpreter stack limit.
 pub const STACK_LIMIT: usize = 1024;
 
-/// EVM stack.
-#[derive(Clone, Debug, PartialEq, Eq, Hash)]
-#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
+/// EVM stack with [STACK_LIMIT] capacity of words.
+#[derive(Debug, PartialEq, Eq, Hash)]
+#[cfg_attr(feature = "serde", derive(serde::Serialize))]
 pub struct Stack {
     /// The underlying data of the stack.
     data: Vec<U256>,
@@ -64,6 +64,12 @@ impl Stack {
         &self.data
     }
 
+    /// Consumes the stack and returns the underlying data.
+    #[inline]
+    pub fn into_data(self) -> Vec<U256> {
+        self.data
+    }
+
     /// Removes the topmost element from the stack and returns it, or `StackUnderflow` if it is
     /// empty.
     #[inline]
@@ -304,6 +310,25 @@ impl Stack {
     }
 }
 
+#[cfg(feature = "serde")]
+impl<'de> serde::Deserialize<'de> for Stack {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let mut data = Vec::<U256>::deserialize(deserializer)?;
+        if data.len() > STACK_LIMIT {
+            return Err(serde::de::Error::custom(format!(
+                "stack size exceeds limit: {} > {}",
+                data.len(),
+                STACK_LIMIT
+            )));
+        }
+        data.reserve(STACK_LIMIT - data.len());
+        Ok(Self { data })
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/crates/revm/src/inspector/eip3155.rs b/crates/revm/src/inspector/eip3155.rs
index 6a3bf9a6c5..a10dbf265a 100644
--- a/crates/revm/src/inspector/eip3155.rs
+++ b/crates/revm/src/inspector/eip3155.rs
@@ -1,6 +1,6 @@
 use crate::{
     inspectors::GasInspector,
-    interpreter::{opcode, CallInputs, CreateInputs, Interpreter, InterpreterResult, Stack},
+    interpreter::{opcode, CallInputs, CreateInputs, Interpreter, InterpreterResult},
     primitives::{db::Database, hex, Address, U256},
     EvmContext, Inspector,
 };
@@ -18,7 +18,7 @@ pub struct TracerEip3155 {
     #[allow(dead_code)]
     trace_return_data: bool,
 
-    stack: Stack,
+    stack: Vec<U256>,
     pc: usize,
     opcode: u8,
     gas: u64,
@@ -33,7 +33,7 @@ impl TracerEip3155 {
             gas_inspector: GasInspector::default(),
             trace_mem,
             trace_return_data,
-            stack: Stack::new(),
+            stack: Default::default(),
             pc: 0,
             opcode: 0,
             gas: 0,
@@ -52,7 +52,7 @@ impl<DB: Database> Inspector<DB> for TracerEip3155 {
     // all other information can be obtained from interp.
     fn step(&mut self, interp: &mut Interpreter, context: &mut EvmContext<'_, DB>) {
         self.gas_inspector.step(interp, context);
-        self.stack = interp.stack.clone();
+        self.stack = interp.stack.data().clone();
         self.pc = interp.program_counter();
         self.opcode = interp.current_opcode();
         self.mem_size = interp.shared_memory.len();
@@ -121,7 +121,7 @@ impl<DB: Database> Inspector<DB> for TracerEip3155 {
 
 impl TracerEip3155 {
     fn print_log_line(&mut self, depth: u64, _memory: &[u8]) {
-        let short_stack: Vec<String> = self.stack.data().iter().map(|&b| short_hex(b)).collect();
+        let short_stack: Vec<String> = self.stack.iter().map(|&b| short_hex(b)).collect();
         let log_line = json!({
             "depth": depth,
             "pc": self.pc,

From 01cfef4c0ec3a980d121af4bce548cd1bb53db6e Mon Sep 17 00:00:00 2001
From: Matthias Seitz <matthias.seitz@outlook.de>
Date: Wed, 22 Nov 2023 21:49:54 +0100
Subject: [PATCH 2/2] use alloc

---
 crates/interpreter/src/interpreter/stack.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crates/interpreter/src/interpreter/stack.rs b/crates/interpreter/src/interpreter/stack.rs
index 7b82b5ceed..7a05ad0840 100644
--- a/crates/interpreter/src/interpreter/stack.rs
+++ b/crates/interpreter/src/interpreter/stack.rs
@@ -318,7 +318,7 @@ impl<'de> serde::Deserialize<'de> for Stack {
     {
         let mut data = Vec::<U256>::deserialize(deserializer)?;
         if data.len() > STACK_LIMIT {
-            return Err(serde::de::Error::custom(format!(
+            return Err(serde::de::Error::custom(alloc::format!(
                 "stack size exceeds limit: {} > {}",
                 data.len(),
                 STACK_LIMIT