Mounting floppies

[Neil Rickert]

Users should be able to mount floppies.  But it would take some
internal modifications.

What is needed is for the kernel to ignore the suid and sgid mode flags
for a disk mounted by other than root.  Physically changing all of the
flags is just a time waste.  The kernel already keeps information in
memory about each mounted file system.  It needs to keep an additional
mode flag for the file system which is automatically ANDed with all
file modes from files on that file system, to compute an effective
mode.  When the file system is mounted by "root" on a directory owned
by "root" that additional mode flag would consist of all 1's.  In other
cases it would turn off at least the suid and sgid bits, possibly also
the execute bits.

Of course anyone other than root should be permitted to mount only a
file system on a device he has suitable access permissions to, and only
on a directory he owns.  This would prevent mounting a replacment for
/etc  (or even for /tmp).

Once these changes are incorporated into Unix it becomes worth
investigating arrangements where a user on a work station can mount his
work station file system onto a remote system he is connected to.

Neil Rickert, Northern Illinois University.