On Tue, Jun 27, 2023 at 01:47:53PM +0200, Ilya Dryomov wrote:
> On Sun, May 7, 2023 at 7:56 PM Hu Weiwen <huww98@xxxxxxxxxxx> wrote:
> >
> > From: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
> >
> > These are present in the device spec of cephfs. So they should be
> > treated as immutable. Also reject `mount()' calls where options and
> > device spec are inconsistent.
> >
> > Signed-off-by: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
> > ---
> > net/ceph/ceph_common.c | 26 +++++++++++++++++++++-----
> > 1 file changed, 21 insertions(+), 5 deletions(-)
> >
> > diff --git a/net/ceph/ceph_common.c b/net/ceph/ceph_common.c
> > index 4c6441536d55..c59c5ccc23a8 100644
> > --- a/net/ceph/ceph_common.c
> > +++ b/net/ceph/ceph_common.c
> > @@ -440,17 +440,33 @@ int ceph_parse_param(struct fs_parameter *param, struct ceph_options *opt,
> > break;
> >
> > case Opt_fsid:
> > - err = ceph_parse_fsid(param->string, &opt->fsid);
> > + {
> > + struct ceph_fsid fsid;
> > +
> > + err = ceph_parse_fsid(param->string, &fsid);
> > if (err) {
> > error_plog(&log, "Failed to parse fsid: %d", err);
> > return err;
> > }
> > - opt->flags |= CEPH_OPT_FSID;
> > +
> > + if (!(opt->flags & CEPH_OPT_FSID)) {
> > + opt->fsid = fsid;
> > + opt->flags |= CEPH_OPT_FSID;
> > + } else if (ceph_fsid_compare(&opt->fsid, &fsid)) {
> > + error_plog(&log, "fsid already set to %pU",
> > + &opt->fsid);
> > + return -EINVAL;
> > + }
> > break;
> > + }
> > case Opt_name:
> > - kfree(opt->name);
> > - opt->name = param->string;
> > - param->string = NULL;
> > + if (!opt->name) {
> > + opt->name = param->string;
> > + param->string = NULL;
> > + } else if (strcmp(opt->name, param->string)) {
> > + error_plog(&log, "name already set to %s", opt->name);
> > + return -EINVAL;
> > + }
> > break;
> > case Opt_secret:
> > ceph_crypto_key_destroy(opt->key);
> > --
> > 2.25.1
> >
>
> Hi Hu,
>
> I'm not following the reason for singling out "fsid" and "name" in
> ceph_parse_param() in net/ceph. All options are overridable in the
> sense that the last setting wins on purpose, this is a long-standing
> behavior. Allowing "key" or "secret" to be overridden while rejecting
> the corresponding override for "name" is weird.
>
> If there is a desire to treat "fsid" and "name" specially in CephFS
> because they are coming from the device spec and aren't considered to
> be mount options in the usual sense, I would suggest enforcing this
> behavior in fs/ceph (and only when the device spec syntax is used).
>
> Thanks,
>
> Ilya
Hi Ilya,
I agree. Thank you for your advise. Please see my patch v2.
Hu Weiwen
