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    I've seen a few "nothing is broken" posts. Things _are_ broken.
    Leaving aside the issue of a bloated /dev full of junk I don't
    have, there are some serious reasons for a devfs. It needs to
    be a real devfs too, not some weak hack.

    *** Read-only filesystems ***
    The FSSTND (Linux filesystem standard document) suggests the possibility
    of a read-only root filesystem. Read-only filesystems help reduce the
    chance that mistakes, crashes, and crackers (evil hackers) might damage
    something. The Linux root filesystem can not be read-only because the
    normal /dev must be read-write to allow tty ownership changes. With the
    devfs, the root filesystem can be read-only. The current /dev could be
    trouble for Linux embedded in ROM.

    *** NTFS ***
    With a devfs, NTFS could be used as the root filesystem. The NT
    filesystem supports POSIX file storage, but does not support device
    files. Linux support for NTFS is in development, but NTFS will not
    be useable as a root filesystem until the normal /dev can be avoided.

    *** PTY security ***
    When a pty is needed, root must change the owner. When that pty is
    not needed anymore, root must change the owner back again. There are
    problems with that method, because it means that many programs should
    be setuid root. Emacs shell windows leave a security hole because the
    pty owner never gets changed. Many programs can fail to change the pty
    owner back.
    With devfs, the kernel can chown ptys back to root when a process
    does not need them anymore. The kernel might be able to let normal
    users chown their own pty or it might perform the chown automatically.

     \ /
      Last update: 2005-03-22 13:41    [W:0.019 / U:0.780 seconds]
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