handleContainerExit: put a timeout on containerd DeleteTask

Also move c.Lock() below containerd delete task, as it doesn't seem that
there is any necessity to hold the container lock while containerd is
killing the task.

This fixes a potential edge-case where containerd delete task hangs, and
thereafter all operations on the container would hang forever, as this
function is holding onto the container lock.

Signed-off-by: Cam <gh@sparr.email>

daemon/monitor.go

@@ -26,15 +26,17 @@ func (daemon *Daemon) setStateCounter(c *container.Container) {
 
 func (daemon *Daemon) handleContainerExit(c *container.Container, e *libcontainerdtypes.EventInfo) error {
 	c.Lock()
-
-	ec, et, err := daemon.containerd.DeleteTask(context.Background(), c.ID)
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	ec, et, err := daemon.containerd.DeleteTask(ctx, c.ID)
+	cancel()
 	if err != nil {
-		logrus.WithError(err).Warnf("failed to delete container %s from containerd", c.ID)
+		logrus.WithError(err).WithField("container", c.ID).Warnf("failed to delete container from containerd")
 	}
 
-	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	ctx, cancel = context.WithTimeout(context.Background(), 2*time.Second)
 	c.StreamConfig.Wait(ctx)
 	cancel()
+
 	c.Reset(false)
 
 	exitStatus := container.ExitStatus{