netfilter: fib: check correct rtable in vrf setups

[ Upstream commit 05ef7055debc804e8083737402127975e7244fc4 ]

We need to init l3mdev unconditionally, else main routing table is searched
and incorrect result is returned unless strict (iif keyword) matching is
requested.

Next patch adds a selftest for this.

Fixes: 2a8a7c0eaa87 ("netfilter: nft_fib: Fix for rpath check with VRF devices")
Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1761
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c
index 0f6a58558bab6fbb90fd6d26dc6e11a7e8e0b544..273b64e3f2f9268b846e4521b26c1455df3a969a 100644 (file)
--- a/net/ipv4/netfilter/nft_fib_ipv4.c
+++ b/net/ipv4/netfilter/nft_fib_ipv4.c
@@ -66,6 +66,7 @@ void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
                .flowi4_scope = RT_SCOPE_UNIVERSE,
                .flowi4_iif = LOOPBACK_IFINDEX,
                .flowi4_uid = sock_net_uid(nft_net(pkt), NULL),
+               .flowi4_l3mdev = l3mdev_master_ifindex_rcu(nft_in(pkt)),
        };
        const struct net_device *oif;
        const struct net_device *found;
@@ -84,9 +85,6 @@ 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_l3mdev = 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 4239b8056b5bd808ce648beab9be043800299213..1a08b00aa321382467da42914ad0da236f88a660 100644 (file)
--- a/net/ipv6/netfilter/nft_fib_ipv6.c
+++ b/net/ipv6/netfilter/nft_fib_ipv6.c
@@ -37,8 +37,6 @@ 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) {
-               fl6->flowi6_l3mdev = l3mdev_master_ifindex_rcu(dev);
        }
 
        if (ipv6_addr_type(&fl6->saddr) & IPV6_ADDR_UNICAST)
@@ -71,6 +69,8 @@ static u32 __nft_fib6_eval_type(const struct nft_fib *priv,
        else if (priv->flags & NFTA_FIB_F_OIF)
                dev = nft_out(pkt);
 
+       fl6.flowi6_l3mdev = l3mdev_master_ifindex_rcu(dev);
+
        nft_fib6_flowi_init(&fl6, priv, pkt, dev, iph);
 
        if (dev && nf_ipv6_chk_addr(nft_net(pkt), &fl6.daddr, dev, true))
@@ -161,6 +161,7 @@ void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs,
                .flowi6_iif = LOOPBACK_IFINDEX,
                .flowi6_proto = pkt->tprot,
                .flowi6_uid = sock_net_uid(nft_net(pkt), NULL),
+               .flowi6_l3mdev = l3mdev_master_ifindex_rcu(nft_in(pkt)),
        };
        struct rt6_info *rt;
        int lookup_flags;