From f90cbcce20a3a7ba47f1cef8ca47a88fb3ac54b5 Mon Sep 17 00:00:00 2001
From: Matt Joiner <anacrolix@gmail.com>
Date: Mon, 13 Apr 2020 19:13:59 +1000
Subject: [PATCH] Fix locks around Torrent.announceRequest

---
 torrent.go         | 3 ++-
 tracker_scraper.go | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/torrent.go b/torrent.go
index 51a8cce5..c12d5211 100644
--- a/torrent.go
+++ b/torrent.go
@@ -1321,8 +1321,9 @@ func (t *Torrent) startScrapingTracker(_url string) {
 				t.logger.WithText(func(m log.Msg) string {
 					return fmt.Sprintf("%q: %v", u.String(), m.Text())
 				}).WithValues(log.Debug))}
+			ar := t.announceRequest(tracker.Started)
 			go func() {
-				err := wst.TrackerClient.Run(t.announceRequest(tracker.Started), u.String())
+				err := wst.TrackerClient.Run(ar, u.String())
 				if err != nil {
 					t.logger.WithValues(log.Error).Printf(
 						"error running websocket tracker announcer for %q: %v",
diff --git a/tracker_scraper.go b/tracker_scraper.go
index b664b2bf..c580afc9 100644
--- a/tracker_scraper.go
+++ b/tracker_scraper.go
@@ -113,9 +113,9 @@ func (me *trackerScraper) announce(event tracker.AnnounceEvent) (ret trackerAnno
 		ret.Err = fmt.Errorf("error getting ip: %s", err)
 		return
 	}
-	me.t.cl.lock()
+	me.t.cl.rLock()
 	req := me.t.announceRequest(event)
-	me.t.cl.unlock()
+	me.t.cl.rUnlock()
 	//log.Printf("announcing %s %s to %q", me.t, req.Event, me.u.String())
 	res, err := tracker.Announce{
 		HTTPProxy:  me.t.cl.config.HTTPProxy,