Re: [PATCH net-next] net: ipv6: avoid accepting values greater than 2 for accept_untracked_na

From: Jaehee
Date: Wed Jul 20 2022 - 14:38:03 EST


On Wed, Jul 20, 2022 at 4:26 AM Nicolas Dichtel
<nicolas.dichtel@xxxxxxxxx> wrote:
>
>
> Le 20/07/2022 à 08:52, Jaehee Park a écrit :
> > The accept_untracked_na sysctl changed from a boolean to an integer
> > when a new knob '2' was added. This patch provides a safeguard to avoid
> > accepting values that are not defined in the sysctl. When setting a
> > value greater than 2, the user will get an 'invalid argument' warning.
> >
> > Signed-off-by: Jaehee Park <jhpark1013@xxxxxxxxx>
> > Suggested-by: Nicolas Dichtel <nicolas.dichtel@xxxxxxxxx>
> > Suggested-by: Roopa Prabhu <roopa@xxxxxxxxxx>
> > ---
> > net/ipv6/addrconf.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> > index 6ed807b6c647..d3e77ea24f05 100644
> > --- a/net/ipv6/addrconf.c
> > +++ b/net/ipv6/addrconf.c
> > @@ -7042,9 +7042,9 @@ static const struct ctl_table addrconf_sysctl[] = {
> > .data = &ipv6_devconf.accept_untracked_na,
> > .maxlen = sizeof(int),
> > .mode = 0644,
> > - .proc_handler = proc_dointvec,
> > + .proc_handler = proc_dointvec_minmax,
> > .extra1 = (void *)SYSCTL_ZERO,
> > - .extra2 = (void *)SYSCTL_ONE,
> > + .extra2 = (void *)SYSCTL_TWO,
> Nit: the cast is useless:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/linux/sysctl.h#n40
>

O yes thank you for pointing that out! I just sent a v2 for your review.

>
> Regards,
> Nicolas

Thanks,
Jaehee