* src/copy.c (copy_internal): Omit the group- or other-writeable
permissions when creating a directory, to avoid a race condition
if the special mode bits aren't right just after the directory is
created.
* src/cp.c (make_dir_parents_private): Likewise.
* tests/cp/parent-perm-race: Test for the "cp --preserve=mode"
race fix in copy.c.
b28a8851ed