On Mon, Oct 07, 2019 at 10:31:04AM -0400, Olga Kornievskaia wrote:
> On Wed, Oct 2, 2019 at 3:55 PM J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote:
> >
> > On Mon, Sep 16, 2019 at 05:13:52PM -0400, Olga Kornievskaia wrote:
> > > @@ -1956,6 +1964,45 @@ static void svcxdr_init_encode(struct svc_rqst *rqstp,
> > > - rqstp->rq_auth_slack;
> > > }
> > >
> > > +#ifdef CONFIG_NFSD_V4_2_INTER_SSC
> > > +static __be32
> > > +check_if_stalefh_allowed(struct nfsd4_compoundargs *args)
> > > +{
> > > + struct nfsd4_op *op, *current_op, *saved_op;
> >
> > current_op and saved_op need to be initialized to NULL here.
> >
> > > + struct nfsd4_copy *copy;
> > > + struct nfsd4_putfh *putfh;
> > > + int i;
> > > +
> > > + /* traverse all operation and if it's a COPY compound, mark the
> > > + * source filehandle to skip verification
> > > + */
> > > + for (i = 0; i < args->opcnt; i++) {
> > > + op = &args->ops[i];
> > > + if (op->opnum == OP_PUTFH)
> > > + current_op = op;
> > > + else if (op->opnum == OP_SAVEFH)
> > > + saved_op = current_op;
> > > + else if (op->opnum == OP_RESTOREFH)
> > > + current_op = saved_op;
> > > + else if (op->opnum == OP_COPY) {
> > > + copy = (struct nfsd4_copy *)&op->u;
> > > + if (!saved_op)
> > > + return nfserr_nofilehandle;
> >
> > Looks like this results in returning an empty compound result with just
> > the bare result. I believe what we need to do is execute all the
> > ops preceding the COPY normally, then return the nofilehandle error on
> > the COPY.
> >
> > One approach might be
> >
> > if (!saved_op) {
> > op->status = nfserr_nofilehandle;
> > return;
> > }
> >
> > and change check_if_stalefh_allowed to have no return value.
>
> Ok thanks. I'm just curious if op->status assignment is necessary or I
> can just do a return. When nfsd4_copy() calls nfs4_verify_copy() it
> would check
> if (!cstate->save_fh.fh_dentry)
> return nfserr_nofilehandle;
Catching the error here might be a little safer if you think there's
ever a risk of messing up the later logic? But, really, either should
work.
Since a real client is never going to hit any interesting cases here, it
could be useful to have a pynfs test or two that sent some weird illegal
compounds.
--b.
>
> >
> > --b.
> >
> > > + putfh = (struct nfsd4_putfh *)&saved_op->u;
> > > + if (!copy->cp_intra)
> > > + putfh->no_verify = true;
> > > + }
> > > + }
> > > + return nfs_ok;
> > > +}
> > ...
> > > @@ -2004,6 +2051,9 @@ static void svcxdr_init_encode(struct svc_rqst *rqstp,
> > > resp->opcnt = 1;
> > > goto encode_op;
> > > }
> > > + status = check_if_stalefh_allowed(args);
> > > + if (status)
> > > + goto out;
> >
> > >
> > > trace_nfsd_compound(rqstp, args->opcnt);
> > > while (!status && resp->opcnt < args->opcnt) {
