diff --git a/pkg/ns/ns_linux.go b/pkg/ns/ns_linux.go index 31ad5f62..a34f9717 100644 --- a/pkg/ns/ns_linux.go +++ b/pkg/ns/ns_linux.go @@ -178,7 +178,16 @@ func (ns *netNS) Do(toRun func(NetNS) error) error { if err = ns.Set(); err != nil { return fmt.Errorf("error switching to ns %v: %v", ns.file.Name(), err) } - defer threadNS.Set() // switch back + defer func() { + err := threadNS.Set() // switch back + if err == nil { + // Unlock the current thread only when we successfully switched back + // to the original namespace; otherwise leave the thread locked which + // will force the runtime to scrap the current thread, that is maybe + // not as optimal but at least always safe to do. + runtime.UnlockOSThread() + } + }() return toRun(hostNS) } @@ -193,6 +202,10 @@ func (ns *netNS) Do(toRun func(NetNS) error) error { var wg sync.WaitGroup wg.Add(1) + // Start the callback in a new green thread so that if we later fail + // to switch the namespace back to the original one, we can safely + // leave the thread locked to die without a risk of the current thread + // left lingering with incorrect namespace. var innerError error go func() { defer wg.Done()