[Libguestfs] [libnbd PATCH 2/2] api: Add STRICT_BOUNDS to nbd_set_strict_mode

[Richard W.M. Jones]

On Fri, Sep 04, 2020 at 04:18:42PM -0500, Eric Blake wrote:
> The NBD protocol states that a 0-length request is undefined; we were
> inconsistent in that we let it through for read, write, and cache, but
> blocked it for trim, zero, and block_status.  The NBD protocol also
> has documented rules on handling access beyond EOF, but we are
> currently wasting traffic to the server when we can give the same
> answer ourselves.  Exposing this as a strictness knob gives the user
> finer-grained control over what behavior they want.
> 
> ---
> 
> Question: should this be split into two flags, one to prevent 0-length
> requests, and the other to prevent out-of-bounds requests?

Looks fine, ACK.

My only comment would be that it might be better to factor the
checking code into a new function -- it looks like the checks only
differ by one errno value.

Two flags could be better here because I can see it might be useful to
disable one check but not the other, but up to you.

Rich.

-- 
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