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    SubjectRe: [PATCH] private mounts
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    >This is why you have identity squashing and/or strong security: to stop
    >the CLIENT administrator impersonating whoever he wants and working
    >around your security measures.

    That's more of a confirmation than a refutation of the statement that NFS
    root squashing is broken. Root squashing itself simply does not squash a
    typical system administrator's ability to get at other people's files.
    "broken" isn't the right word, because as long as you recognize root
    squashing for what it is, it's working as designed. It just isn't what it
    appears to be.

    But, in the context of the current thread, I think the perception of NFS
    root squashing as something broken and not to be built upon with private
    mounts has to do with the fact that it messes up Linux's basic file
    permission scheme: a process with CAP_DAC_OVERRIDE can get EACCES.
    EACCESS means discretionary access controls (DAC) prevent access. So this
    behavior is unexpected and unnatural. Worse, an operation can succeed
    _without_ CAP_DAC_OVERRIDE, but not _with_ it. I've seen this behavior
    cause trouble a number of times -- mostly because it's entirely
    unanticipated.

    --
    Bryan Henderson IBM Almaden Research Center
    San Jose CA Filesystems
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