Upstream patch: https://git.savannah.gnu.org/cgit/libcdio.git/commit/?id=6f2426e8bf4dc5269ccbd9fbfa94340895f8be6e
--- lib/driver/osx.c.orig
+++ lib/driver/osx.c
@@ -1232,7 +1232,7 @@
     CFRange range;
     CFIndex buf_len;
 
-    buf_len = CFDataGetLength( data ) + 1;
+    buf_len = CFDataGetLength( data );
     range = CFRangeMake( 0, buf_len );
 
     if( ( p_env->pTOC = (CDTOC *)malloc( buf_len ) ) != NULL ) {