On Wed, 2022-06-29 at 09:02 +0800, Ian Kent wrote:
>
> On 28/6/22 22:34, Trond Myklebust wrote:
> > On Tue, 2022-06-28 at 08:25 +0800, Ian Kent wrote:
> > > The valid values of nfs options port and mountport are 0 to
> > > USHRT_MAX.
> > >
> > > The fs parser will return a fail for port values that are
> > > negative
> > > and the sloppy option handling then returns success.
> > >
> > > But the sloppy option handling is meant to return success for
> > > invalid
> > > options not valid options with invalid values.
> > >
> > > Parsing these values as s32 rather than u32 prevents the parser
> > > from
> > > returning a parse fail allowing the later USHRT_MAX option check
> > > to
> > > correctly return a fail in this case. The result check could be
> > > changed
> > > to use the int_32 union variant as well but leaving it as a
> > > uint_32
> > > check avoids using two logical compares instead of one.
> > >
> > > Signed-off-by: Ian Kent <raven@xxxxxxxxxx>
> > > ---
> > > fs/nfs/fs_context.c | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
> > > index 9a16897e8dc6..f4da1d2be616 100644
> > > --- a/fs/nfs/fs_context.c
> > > +++ b/fs/nfs/fs_context.c
> > > @@ -156,14 +156,14 @@ static const struct fs_parameter_spec
> > > nfs_fs_parameters[] = {
> > > fsparam_u32 ("minorversion", Opt_minorversion),
> > > fsparam_string("mountaddr", Opt_mountaddr),
> > > fsparam_string("mounthost", Opt_mounthost),
> > > - fsparam_u32 ("mountport", Opt_mountport),
> > > + fsparam_s32 ("mountport", Opt_mountport),
> > > fsparam_string("mountproto", Opt_mountproto),
> > > fsparam_u32 ("mountvers", Opt_mountvers),
> > > fsparam_u32 ("namlen", Opt_namelen),
> > > fsparam_u32 ("nconnect", Opt_nconnect),
> > > fsparam_u32 ("max_connect", Opt_max_connect),
> > > fsparam_string("nfsvers", Opt_vers),
> > > - fsparam_u32 ("port", Opt_port),
> > > + fsparam_s32 ("port", Opt_port),
> > > fsparam_flag_no("posix", Opt_posix),
> > > fsparam_string("proto", Opt_proto),
> > > fsparam_flag_no("rdirplus", Opt_rdirplus),
> > >
> > >
> > Why don't we just check for the ENOPARAM return value from
> > fs_parse()?
>
> In this case I think the return will be EINVAL.
My point is that 'sloppy' is only supposed to work to suppress the
error in the case where an option is not found by the parser. That
corresponds to the error ENOPARAM.
>
> I think that's a bit to general for this case.
>
> This seemed like the most sensible way to fix it.
>
Your patch works around just one symptom of the problem instead of
addressing the root cause.
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx
