Merge tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull mount fixes from Al Viro:
 "Several mount-related fixes"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  userns and mnt_idmap leak in open_tree_attr(2)
  attach_recursive_mnt(): do not lock the covering tree when sliding something under it
  replace collect_mounts()/drop_collected_mounts() with a safer variant