Subject: Re: exporting -ro nfs
To: None <tech-kern@NetBSD.org, tech-security@NetBSD.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-security
Date: 01/26/2007 16:31:08
> The mountd won't respond to a mount request for /usr unless "alldirs"
> was specified, but it is true that a "bad guy" could guess/replay a
> file handle for /usr and go from there.

I think it's actually worse than that; given a file handle for
/usr/foo/bar/blee, someone not running normal client code could do ..
lookups to walk up as far as the server will permit (which usually
means, to the mount point on the server - /usr in this case).

It's been a while since I had my hands dirty with NFS, but I'm pretty
sure that's how it generally works.

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