From 7ef0b6e66e834ac0fcb7cf95ed17835a04a1f32d Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Tue, 27 Dec 2022 19:09:09 +0900
Subject: [PATCH] mruby-io/io.c (mrb_io_initialize_copy): dupe the buffer

---
 mrbgems/mruby-io/src/io.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mrbgems/mruby-io/src/io.c b/mrbgems/mruby-io/src/io.c
index 958a0b3bc..9c130e496 100644
--- a/mrbgems/mruby-io/src/io.c
+++ b/mrbgems/mruby-io/src/io.c
@@ -621,7 +621,7 @@ mrb_io_initialize_copy(mrb_state *mrb, mrb_value copy)
   DATA_PTR(copy) = fptr_copy;
 
   buf = mrb_iv_get(mrb, orig, MRB_IVSYM(buf));
-  mrb_iv_set(mrb, copy, MRB_IVSYM(buf), buf);
+  mrb_iv_set(mrb, copy, MRB_IVSYM(buf), mrb_str_dup(mrb, buf));
 
   fptr_copy->fd = mrb_dup(mrb, fptr_orig->fd, &failed);
   if (failed) {