From 82adfb611d2c8c7f070297210c2b9854490887e5 Mon Sep 17 00:00:00 2001
From: "Timothy B. Terriberry" <tterribe@xiph.org>
Date: Tue, 15 Dec 2020 16:23:16 -0800
Subject: [PATCH] Fix intermediate overflow in op_pcm_total().

Although link enumeration ensures the return value is in range, the
 order of operations allows the intermediate value pcm_total+diff
 to overflow the range of a 64-bit int.
Add parentheses to ensure this does not happen.
Thanks to Felcia Lim for the report.

Fixes #2330
---
 src/opusfile.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/opusfile.c b/src/opusfile.c
index 5bf9f91..144e02c 100644
--- a/src/opusfile.c
+++ b/src/opusfile.c
@@ -1753,7 +1753,7 @@ ogg_int64_t op_pcm_total(const OggOpusFile *_of,int _li){
   }
   OP_ALWAYS_TRUE(!op_granpos_diff(&diff,
    links[_li].pcm_end,links[_li].pcm_start));
-  return pcm_total+diff-links[_li].head.pre_skip;
+  return pcm_total+(diff-links[_li].head.pre_skip);
 }
 
 const OpusHead *op_head(const OggOpusFile *_of,int _li){
-- 
2.27.0