From: Phil Sutter phil@nwl.cc
[ Upstream commit 2a8a7c0eaa8747c16aa4a48d573aa920d5c00a5c ]
Analogous to commit b575b24b8eee3 ("netfilter: Fix rpfilter dropping vrf packets by mistake") but for nftables fib expression: Add special treatment of VRF devices so that typical reverse path filtering via 'fib saddr . iif oif' expression works as expected.
Fixes: f6d0cbcf09c50 ("netfilter: nf_tables: add fib expression") Signed-off-by: Phil Sutter phil@nwl.cc Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/netfilter/nft_fib_ipv4.c | 3 +++ net/ipv6/netfilter/nft_fib_ipv6.c | 6 +++++- 2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c index b75cac69bd7e..7ade04ff972d 100644 --- a/net/ipv4/netfilter/nft_fib_ipv4.c +++ b/net/ipv4/netfilter/nft_fib_ipv4.c @@ -83,6 +83,9 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, else oif = NULL;
+ if (priv->flags & NFTA_FIB_F_IIF) + fl4.flowi4_oif = l3mdev_master_ifindex_rcu(oif); + if (nft_hook(pkt) == NF_INET_PRE_ROUTING && nft_fib_is_loopback(pkt->skb, nft_in(pkt))) { nft_fib_store_result(dest, priv, nft_in(pkt)); diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c index 8970d0b4faeb..1d7e520d9966 100644 --- a/net/ipv6/netfilter/nft_fib_ipv6.c +++ b/net/ipv6/netfilter/nft_fib_ipv6.c @@ -41,6 +41,9 @@ 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; }
if (ipv6_addr_type(&fl6->saddr) & IPV6_ADDR_UNICAST) @@ -197,7 +200,8 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, if (rt->rt6i_flags & (RTF_REJECT | RTF_ANYCAST | RTF_LOCAL)) goto put_rt_err;
- if (oif && oif != rt->rt6i_idev->dev) + if (oif && oif != rt->rt6i_idev->dev && + l3mdev_master_ifindex_rcu(rt->rt6i_idev->dev) != oif->ifindex) goto put_rt_err;
nft_fib_store_result(dest, priv, rt->rt6i_idev->dev);