utf32.patch

diff --git a/ext/mbstring/oniguruma/src/utf32_be.c b/ext/mbstring/oniguruma/src/utf32_be.c
index 92476ec033..dc1eb058a5 100644
--- a/ext/mbstring/oniguruma/src/utf32_be.c
+++ b/ext/mbstring/oniguruma/src/utf32_be.c
@@ -65,8 +65,9 @@ utf32be_is_mbc_newline(const UChar* p, const UChar* end)
 }

 static OnigCodePoint
-utf32be_mbc_to_code(const UChar* p, const UChar* end ARG_UNUSED)
+utf32be_mbc_to_code(const UChar* p, const UChar* end)
 {
+  if (p + 4 > end) return (OnigCodePoint ) NULL;
   return (OnigCodePoint )(((p[0] * 256 + p[1]) * 256 + p[2]) * 256 + p[3]);
 }