From 4ccc82be921563056b37127997b8ca98dc25bc3e Mon Sep 17 00:00:00 2001
From: cdetrio <cdetrio@gmail.com>
Date: Sun, 20 Aug 2017 00:03:47 -0400
Subject: [PATCH] fix panic in parity-evm json tracer (#6338)

---
 evmbin/src/display/json.rs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/evmbin/src/display/json.rs b/evmbin/src/display/json.rs
index f2621121e..e259eec7a 100644
--- a/evmbin/src/display/json.rs
+++ b/evmbin/src/display/json.rs
@@ -116,6 +116,9 @@ impl trace::VMTracer for Informant {
 		self.stack.extend_from_slice(stack_push);
 
 		if let Some((pos, data)) = mem_diff {
+			if self.memory.len() < (pos + data.len()) {
+				self.memory.resize(pos + data.len(), 0);
+			}
 			self.memory[pos..pos + data.len()].copy_from_slice(data);
 		}