Re: [PATCH v2 2/6] sysctl: Fixes nsm_local_state bounds

[Nicolas Bouchinet]

On 2/24/25 15:38, Chuck Lever wrote:
> On 2/24/25 4:58 AM, nicolas.bouchinet@xxxxxxxxxxx wrote:
> > From: Nicolas Bouchinet <nicolas.bouchinet@xxxxxxxxxxx>
> >
> > Bound nsm_local_state sysctl writings between SYSCTL_ZERO
> > and SYSCTL_INT_MAX.
> >
> > The proc_handler has thus been updated to proc_dointvec_minmax.
> >
> > Signed-off-by: Nicolas Bouchinet <nicolas.bouchinet@xxxxxxxxxxx>
> > ---
> >   fs/lockd/svc.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
> > index 2c8eedc6c2cc9..984ab233af8b6 100644
> > --- a/fs/lockd/svc.c
> > +++ b/fs/lockd/svc.c
> > @@ -461,7 +461,9 @@ static const struct ctl_table nlm_sysctls[] = {
> >   		.data		= &nsm_local_state,
> >   		.maxlen		= sizeof(int),
> >   		.mode		= 0644,
> > -		.proc_handler	= proc_dointvec,
> > +		.proc_handler	= proc_dointvec_minmax,
> > +		.extra1		= SYSCTL_ZERO,
> > +		.extra2		= SYSCTL_INT_MAX,
> >   	},
> >   };
> >   
> Hi Nicolas -
>
> nsm_local_state is an unsigned 32-bit integer. The type of that value is
> defined by spec, because this value is exchanged between peers on the
> network.
>
> Perhaps this patch should replace proc_dointvec with proc_douintvec
> instead.

Hi Chuck,

Thank's for your review.

If `nsm_local_state` should be set to the
full range of an uint32_t by a user writing in the sysctl, then yes it 
should
use `proc_douintvec` instead of limiting it to SYSCTL_INT_MAX value 
(INT_MAX).

I've used `proc_dointvec_minmax` since it already used `proc_dointvec` 
and thus
was already capped at INT_MAX.

Best regards,

Nicolas