From bbfb1bd2291a1477a7f1548a1f1a1ce64c226d34 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Wed, 30 Mar 2022 13:01:10 -0600
Subject: [PATCH] MidiRegion: take reader lock before cloning data into new
 source

---
 libs/ardour/midi_region.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libs/ardour/midi_region.cc b/libs/ardour/midi_region.cc
index 54b955a2a5..c89a186350 100644
--- a/libs/ardour/midi_region.cc
+++ b/libs/ardour/midi_region.cc
@@ -149,6 +149,7 @@ MidiRegion::clone (boost::shared_ptr<MidiSource> newsrc, ThawList* tl) const
 		   take a lock on newsrc.
 		*/
 
+		Source::ReaderLock lm (ms->mutex());
 		if (ms->write_to (lm, newsrc, bbegin, bend)) {
 			return boost::shared_ptr<MidiRegion> ();
 		}