Re: [PATCH v2 1/1] netfilter: nat: add a range check for l3/l4 protonum

Will Deacon
2020-09-01T16:13:34Z

Hi Will, Pablo,

On Tue, Aug 04, 2020 at 01:37:11PM +0200, Pablo Neira Ayuso wrote:
> This patch is much smaller and if you confirm this is address the
> issue, then this is awesome.

Did that ever get confirmed? AFAICT, nothing ended up landing in the stable
trees for this.

Cheers,

Will

> On Mon, Aug 03, 2020 at 06:31:56PM +0000, William Mcvicker wrote:
> [...]
> > diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
> > index 31fa94064a62..56d310f8b29a 100644
> > --- a/net/netfilter/nf_conntrack_netlink.c
> > +++ b/net/netfilter/nf_conntrack_netlink.c
> > @@ -1129,6 +1129,8 @@ ctnetlink_parse_tuple(const struct nlattr * const cda[],
> > if (!tb[CTA_TUPLE_IP])
> > return -EINVAL;
> >
> > + if (l3num >= NFPROTO_NUMPROTO)
> > + return -EINVAL;
>
> l3num can only be either NFPROTO_IPV4 or NFPROTO_IPV6.
>
> Other than that, bail out with EOPNOTSUPP.
>
> Thank you.