Re: [PATCH] NFSv4: Fix attribute length

["J. Bruce Fields" <bfields@fieldses.org>]

On Wed, Jul 24, 2013 at 02:30:58PM +0000, Myklebust, Trond wrote:
> On Wed, 2013-07-24 at 10:14 -0400, J. Bruce Fields wrote:
> > From: "J. Bruce Fields" <bfields@redhat.com>
> > 
> > The calculation of attribute length fields is too high by four because
> > it incorrectly includes the length field itself.
> > 
> > This regression was introduced by
> > b4a2cf76ab7c08628c62b2062dacefa496b59dfd "NFSv4: Fix a regression
> > against the FreeBSD server" and causes OPENs to the Linux NFS server to
> > fail with BADXDR errors (translated by the client into EIO).
> > 
> > Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> > ---
> >  fs/nfs/nfs4xdr.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > I thought you guys had automated testing against the Linux server?  How
> > did this slip through into upstream?
> > 
> > --b.
> > 
> > diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
> > index c74d616..d6d6754 100644
> > --- a/fs/nfs/nfs4xdr.c
> > +++ b/fs/nfs/nfs4xdr.c
> > @@ -1118,7 +1118,7 @@ static void encode_attrs(struct xdr_stream *xdr, const struct iattr *iap,
> >  				len, ((char *)p - (char *)q) + 4);
> >  		BUG();
> >  	}
> > -	len = (char *)p - (char *)q - (bmval_len << 2);
> > +	len = (char *)p - (char *)q - (bmval_len + 1 << 2);
> >  	*q++ = htonl(bmval0);
> >  	*q++ = htonl(bmval1);
> >  	if (bmval_len == 3)
> 
> Please see commit 4f3cc4809a98a165a9708b72b47de71643797bbd (NFSv4: Fix
> brainfart in attribute length calculation) upstream.

Oh, good, thanks!

But I still don't understand how this made it into upstream in the first
place.

Any NFSv4 testing at all against the Linux server would catch this, and
I thought you had automated testing set up that you could run before
submission.

--b.