From 555e68a19de851edcf9247531744f4045bbedaf7 Mon Sep 17 00:00:00 2001
From: Aleksey Kladov <aleksey.kladov@gmail.com>
Date: Wed, 4 Oct 2017 13:38:24 +0300
Subject: [PATCH] [debug] fix off by one error in DebugObjectToUtf8Array

We've copied exactly `toCopy` bytes, so the byte after the last copied
has index `toCopy`. Note that if `toCopy` is exactly (bufferSize - 1),
the previous code would write to memory outside of the buffer.
---
 runtime/src/main/cpp/KDebug.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/runtime/src/main/cpp/KDebug.cpp b/runtime/src/main/cpp/KDebug.cpp
index 6415abd902f..8418b1c9f50 100644
--- a/runtime/src/main/cpp/KDebug.cpp
+++ b/runtime/src/main/cpp/KDebug.cpp
@@ -52,7 +52,7 @@ RUNTIME_USED KInt Konan_DebugObjectToUtf8Array(KRef obj, char* buffer, KInt buff
   if (data == nullptr) return 0;
   KInt toCopy = data->count_ > bufferSize - 1 ? bufferSize - 1 : data->count_;
   ::memcpy(buffer, ByteArrayAddressOfElementAt(data, 0), toCopy);
-  buffer[toCopy + 1] = '\0';
+  buffer[toCopy] = '\0';
   return toCopy + 1;
 }