From a9df3e48f7b59bc27e115e5b0ad057a642b6fac3 Mon Sep 17 00:00:00 2001
From: Tsuda Kageyu <tsuda.kageyu@gmail.com>
Date: Wed, 10 Oct 2012 21:17:05 +0900
Subject: [PATCH] Fix a bug in updating MP4 tags

---
 taglib/mp4/mp4tag.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/taglib/mp4/mp4tag.cpp b/taglib/mp4/mp4tag.cpp
index fc75fb45..f929ef64 100644
--- a/taglib/mp4/mp4tag.cpp
+++ b/taglib/mp4/mp4tag.cpp
@@ -570,7 +570,7 @@ MP4::Tag::updateOffsets(long delta, long offset)
         atom->offset += delta;
       }
       d->file->seek(atom->offset + 9);
-      ByteVector data = d->file->readBlock(atom->offset - 9);
+      ByteVector data = d->file->readBlock(atom->length - 9);
       unsigned int flags = (ByteVector(1, '\0') + data.mid(0, 3)).toUInt();
       if(flags & 1) {
         long long o = data.mid(7, 8).toLongLong();