Merge pull request #36549 from cjcullen/closetunnel

Automatic merge from submit-queue Close tunnels after failed healthchecks. When we fail an ssh-tunnel healthcheck, we currently leak a file descriptor keeping the SSH connection open. This closes the underlying tunnel before removing our pointer to it. It is possible that the tunnel was functional, but the healthcheck failed for some other reason (e.g. kubelet healthz down), which could close an in-use tunnel, but I think that is acceptable.

Merge pull request #36549 from cjcullen/closetunnel
98c68947 · Kubernetes Submit Queue · GitHub · 2110f72e · 1fdb3ee9 · 98c68947
Commit 98c68947 authored Nov 15, 2016 by Kubernetes Submit Queue Committed by GitHub Nov 15, 2016
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Showing with 6 additions and 3 deletions

ssh.go pkg/ssh/ssh.go +6 -3

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--- a/pkg/ssh/ssh.go
+++ b/pkg/ssh/ssh.go
@@ -380,15 +380,18 @@ func (l *SSHTunnelList) healthCheck(e sshTunnelEntry) error {
 func (l *SSHTunnelList) removeAndReAdd(e sshTunnelEntry) {
 	// Find the entry to replace.
 	l.tunnelsLock.Lock()
-	defer l.tunnelsLock.Unlock()
 	for i, entry := range l.entries {
 		if entry.Tunnel == e.Tunnel {
 			l.entries = append(l.entries[:i], l.entries[i+1:]...)
 			l.adding[e.Address] = true
-			go l.createAndAddTunnel(e.Address)
-			return
+			break
 		}
 	}
+	l.tunnelsLock.Unlock()
+	if err := e.Tunnel.Close(); err != nil {
+		glog.Infof("Failed to close removed tunnel: %v", err)
+	}
+	go l.createAndAddTunnel(e.Address)
 }

 func (l *SSHTunnelList) Dial(net, addr string) (net.Conn, error) {