Re: mount --bind accounting

>> /* No capabilities? What if users do thousands of these? */

> look at mount_is_safe()

Yes, good. My remark means that more tests are required
than those sketched in mount_is_safe(), and that means
that for the time being we can throw out the routine
mount_is_safe(), and remove the test on capable(CAP_SYS_ADMIN)
in do_remount(), and move the same test in do_mount up to
the start: all forms of mount require CAP_SYS_ADMIN.

[side effect: remount read-only upon umount of root fs
may be possible in a few more cases]

Andries