diff --git a/libcontainer/rootfs_linux.go b/libcontainer/rootfs_linux.go index e2e734a8..c4dbe3d5 100644 --- a/libcontainer/rootfs_linux.go +++ b/libcontainer/rootfs_linux.go @@ -668,9 +668,12 @@ func pivotRoot(rootfs string) error { return err } - // Make oldroot rprivate to make sure our unmounts don't propagate to the - // host (and thus bork the machine). - if err := unix.Mount("", ".", "", unix.MS_PRIVATE|unix.MS_REC, ""); err != nil { + // Make oldroot rslave to make sure our unmounts don't propagate to the + // host (and thus bork the machine). We don't use rprivate because this is + // known to cause issues due to races where we still have a reference to a + // mount while a process in the host namespace are trying to operate on + // something they think has no mounts (devicemapper in particular). + if err := unix.Mount("", ".", "", unix.MS_SLAVE|unix.MS_REC, ""); err != nil { return err } // Preform the unmount. MNT_DETACH allows us to unmount /proc/self/cwd.