From 0f4809f366daa77c6e2f5b09d3f05771fe9bf188 Mon Sep 17 00:00:00 2001 From: Brad Fitzpatrick Date: Thu, 18 Feb 2021 14:53:22 -0800 Subject: tun: make NativeTun.Close well behaved, not crash on double close Signed-off-by: Brad Fitzpatrick --- tun/tun_freebsd.go | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) (limited to 'tun/tun_freebsd.go') diff --git a/tun/tun_freebsd.go b/tun/tun_freebsd.go index e0dc2e1..12b44da 100644 --- a/tun/tun_freebsd.go +++ b/tun/tun_freebsd.go @@ -11,6 +11,7 @@ import ( "fmt" "net" "os" + "sync" "syscall" "unsafe" @@ -82,6 +83,7 @@ type NativeTun struct { events chan Event errors chan error routeSocket int + closeOnce sync.Once } func (tun *NativeTun) routineRouteListener(tunIfindex int) { @@ -472,16 +474,18 @@ func (tun *NativeTun) Flush() error { } func (tun *NativeTun) Close() error { - var err3 error - err1 := tun.tunFile.Close() - err2 := tunDestroy(tun.name) - if tun.routeSocket != -1 { - unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR) - err3 = unix.Close(tun.routeSocket) - tun.routeSocket = -1 - } else if tun.events != nil { - close(tun.events) - } + var err1, err2, err3 error + tun.closeOnce.Do(func() { + err1 = tun.tunFile.Close() + err2 = tunDestroy(tun.name) + if tun.routeSocket != -1 { + unix.Shutdown(tun.routeSocket, unix.SHUT_RDWR) + err3 = unix.Close(tun.routeSocket) + tun.routeSocket = -1 + } else if tun.events != nil { + close(tun.events) + } + }) if err1 != nil { return err1 } -- cgit v1.2.3-59-g8ed1b