Re: NFS bug ?!

Marc Lehmann (
Mon, 24 Feb 1997 14:41:03 +0100 (MET)

> and the NFS server never really checks permissions for the open ?

1. there is no such thing as an open in NFS, just read()( and write()
2. the nfs server does never check permissions on a per-user
base.. the design principle with nfs was to have the server
be as simple as possible.
The only permission chekc it does is wether the file
handle it gets is valid and the machine it comes from has access,
you can read/write data and "mount" drives even without mountd running.

the root_squash option - to my knowledge - is a server-side flag
that simply changes uid "0" to uid "-2" or whatever, namely "nobody".

The decision wether a file can be accessed is done by the client
(remember there is no nfs open()), only on a read or write
the server is able to check any permissions.


for a pentium-optimizing gcc, look at

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