diff --git a/eth/downloader/peer.go b/eth/downloader/peer.go
index 44a6e0f5d736b..fa514f1a43522 100644
--- a/eth/downloader/peer.go
+++ b/eth/downloader/peer.go
@@ -246,6 +246,7 @@ func (ps *peerSet) Register(p *peerConnection) error {
 	}
 	p.rates = msgrate.NewTracker(ps.rates.MeanCapacities(), ps.rates.MedianRoundTrip())
 	if err := ps.rates.Track(p.id, p.rates); err != nil {
+		ps.lock.Unlock()
 		return err
 	}
 	ps.peers[p.id] = p
diff --git a/les/downloader/peer.go b/les/downloader/peer.go
index 9d3296de2bba2..1113fb26bcf47 100644
--- a/les/downloader/peer.go
+++ b/les/downloader/peer.go
@@ -359,6 +359,7 @@ func (ps *peerSet) Register(p *peerConnection) error {
 	}
 	p.rates = msgrate.NewTracker(ps.rates.MeanCapacities(), ps.rates.MedianRoundTrip())
 	if err := ps.rates.Track(p.id, p.rates); err != nil {
+		ps.lock.Unlock()
 		return err
 	}
 	ps.peers[p.id] = p