netfilter: rpfilter/fib: Populate flowic_l3mdev field

Use the introduced field for correct operation with VRF devices instead
of conditionally overwriting flowic_oif. This is a partial revert of
commit b575b24b8e ("netfilter: Fix rpfilter dropping vrf packets by
mistake"), implementing a simpler solution.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
This commit is contained in:
Phil Sutter 2022-10-05 18:07:05 +02:00 committed by Florian Westphal
parent 6e31ce831c
commit acc641ab95
4 changed files with 7 additions and 11 deletions

View File

@ -77,7 +77,7 @@ static bool rpfilter_mt(const struct sk_buff *skb, struct xt_action_param *par)
flow.flowi4_mark = info->flags & XT_RPFILTER_VALID_MARK ? skb->mark : 0;
flow.flowi4_tos = iph->tos & IPTOS_RT_MASK;
flow.flowi4_scope = RT_SCOPE_UNIVERSE;
flow.flowi4_oif = l3mdev_master_ifindex_rcu(xt_in(par));
flow.flowi4_l3mdev = l3mdev_master_ifindex_rcu(xt_in(par));
return rpfilter_lookup_reverse(xt_net(par), &flow, xt_in(par), info->flags) ^ invert;
}

View File

@ -84,7 +84,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
oif = NULL;
if (priv->flags & NFTA_FIB_F_IIF)
fl4.flowi4_oif = l3mdev_master_ifindex_rcu(oif);
fl4.flowi4_l3mdev = l3mdev_master_ifindex_rcu(oif);
if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {

View File

@ -37,6 +37,7 @@ static bool rpfilter_lookup_reverse6(struct net *net, const struct sk_buff *skb,
bool ret = false;
struct flowi6 fl6 = {
.flowi6_iif = LOOPBACK_IFINDEX,
.flowi6_l3mdev = l3mdev_master_ifindex_rcu(dev),
.flowlabel = (* (__be32 *) iph) & IPV6_FLOWINFO_MASK,
.flowi6_proto = iph->nexthdr,
.daddr = iph->saddr,
@ -55,9 +56,7 @@ static bool rpfilter_lookup_reverse6(struct net *net, const struct sk_buff *skb,
if (rpfilter_addr_linklocal(&iph->saddr)) {
lookup_flags |= RT6_LOOKUP_F_IFACE;
fl6.flowi6_oif = dev->ifindex;
/* Set flowi6_oif for vrf devices to lookup route in l3mdev domain. */
} else if (netif_is_l3_master(dev) || netif_is_l3_slave(dev) ||
(flags & XT_RPFILTER_LOOSE) == 0)
} else if ((flags & XT_RPFILTER_LOOSE) == 0)
fl6.flowi6_oif = dev->ifindex;
rt = (void *)ip6_route_lookup(net, &fl6, skb, lookup_flags);
@ -72,9 +71,7 @@ static bool rpfilter_lookup_reverse6(struct net *net, const struct sk_buff *skb,
goto out;
}
if (rt->rt6i_idev->dev == dev ||
l3mdev_master_ifindex_rcu(rt->rt6i_idev->dev) == dev->ifindex ||
(flags & XT_RPFILTER_LOOSE))
if (rt->rt6i_idev->dev == dev || (flags & XT_RPFILTER_LOOSE))
ret = true;
out:
ip6_rt_put(rt);

View File

@ -41,9 +41,8 @@ static int nft_fib6_flowi_init(struct flowi6 *fl6, const struct nft_fib *priv,
if (ipv6_addr_type(&fl6->daddr) & IPV6_ADDR_LINKLOCAL) {
lookup_flags |= RT6_LOOKUP_F_IFACE;
fl6->flowi6_oif = get_ifindex(dev ? dev : pkt->skb->dev);
} else if ((priv->flags & NFTA_FIB_F_IIF) &&
(netif_is_l3_master(dev) || netif_is_l3_slave(dev))) {
fl6->flowi6_oif = dev->ifindex;
} else if (priv->flags & NFTA_FIB_F_IIF) {
fl6->flowi6_l3mdev = l3mdev_master_ifindex_rcu(dev);
}
if (ipv6_addr_type(&fl6->saddr) & IPV6_ADDR_UNICAST)