[comp.sys.apollo] mount on SR10

achille@cernvax.UUCP (achille) (11/29/88)

Hi, I've noticed a difference between the 5.3 and the BSD environments
under SR10.
To mount something under SYS5.3, apparently you must be root (as stated in
the man page), even you mount an nfs file system, instead under bsd4.3 you
can mount, at least nfs file systems, without being root.
Is that a 'feature' or what ?
If we agree that mount is dangerous for security, then it must only work for
root, otherwise should be open to anyone, independently of the environment
you are running in. Any idea/comment/explanation ?

Achille Petrilli
Cray & PWS Operations

mike@apollo.COM (Michael Schloss) (12/13/88)

In article <887@cernvax.UUCP> achille@cernvax.UUCP () writes:
>Hi, I've noticed a difference between the 5.3 and the BSD environments
>under SR10.
>To mount something under SYS5.3, apparently you must be root (as stated in
>the man page), even you mount an nfs file system, instead under bsd4.3 you
>can mount, at least nfs file systems, without being root.
>Is that a 'feature' or what ?
>If we agree that mount is dangerous for security, then it must only work for
>root, otherwise should be open to anyone, independently of the environment
>you are running in. Any idea/comment/explanation ?
>
>Achille Petrilli
>Cray & PWS Operations

Hi.  I'm the Apollo engineer that worked on UNIX mount for SR10 so I can
probably best answer your question.  To put it as simply as possible it
is a compromise between our need to be System V compliant and our need
to best support our users in a workstation environment.  The System V
Validation Suite (SVVS) requires that the SYSV mount call fail for non-root
users.  This had to be balanced against the fact that current users of
our workstations use floppies and we couldn't just break their applications.
The reason that the BSD mount doesn't check for root privileges is that
we are not required by contract to do this.  There is no real security loss
here because a user is able to mount a filesystem using the AEGIS command
mtvol without root/locksmith privileges.  One idea we are looking at is a
restricted mount (all setuid turned off) but this would be part of a future
release when we address other security issues.

Mike Schloss
mike@apollo.com