net: Fix vti use case with oif in dst lookups

Steffen reported that the recent change to add oif to dst lookups breaks
the VTI use case. The problem is that with the oif set in the flow struct
the comparison to the nh_oif is triggered. Fix by splitting the
FLOWI_FLAG_VRFSRC into 2 flags -- one that triggers the vrf device cache
bypass (FLOWI_FLAG_VRFSRC) and another telling the lookup to not compare
nh oif (FLOWI_FLAG_SKIP_NH_OIF).

Fixes: 42a7b32b73d6 ("xfrm: Add oif to dst lookups")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/vrf.c b/drivers/net/vrf.c
index e7094fbd75685998bb5ee492367e686c133a2e15..488c6f50df736968cee60af48d0360924a9f2e2b 100644 (file)
--- a/drivers/net/vrf.c
+++ b/drivers/net/vrf.c
@@ -193,7 +193,8 @@ static netdev_tx_t vrf_process_v4_outbound(struct sk_buff *skb,
                .flowi4_oif = vrf_dev->ifindex,
                .flowi4_iif = LOOPBACK_IFINDEX,
                .flowi4_tos = RT_TOS(ip4h->tos),
-               .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_VRFSRC,
+               .flowi4_flags = FLOWI_FLAG_ANYSRC | FLOWI_FLAG_VRFSRC |
+                               FLOWI_FLAG_SKIP_NH_OIF,
                .daddr = ip4h->daddr,
        };
 

diff --git a/include/net/flow.h b/include/net/flow.h
index acd6a096250e65e149db68d18b22d8dd320b6b39..9b85db85f13cfc2c11713da810260d4da554bde3 100644 (file)
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -35,6 +35,7 @@ struct flowi_common {
 #define FLOWI_FLAG_ANYSRC              0x01
 #define FLOWI_FLAG_KNOWN_NH            0x02
 #define FLOWI_FLAG_VRFSRC              0x04
+#define FLOWI_FLAG_SKIP_NH_OIF         0x08
        __u32   flowic_secid;
        struct flowi_tunnel flowic_tun_key;
 };

diff --git a/include/net/route.h b/include/net/route.h
index cc61cb95f059152bc8cc58c0a2cacb2d9099e103..f46af256880cd9ff0f9fccc503d7cdc83ef3cbd3 100644 (file)
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -255,7 +255,7 @@ static inline void ip_route_connect_init(struct flowi4 *fl4, __be32 dst, __be32
                flow_flags |= FLOWI_FLAG_ANYSRC;
 
        if (netif_index_is_vrf(sock_net(sk), oif))
-               flow_flags |= FLOWI_FLAG_VRFSRC;
+               flow_flags |= FLOWI_FLAG_VRFSRC | FLOWI_FLAG_SKIP_NH_OIF;
 
        flowi4_init_output(fl4, oif, sk->sk_mark, tos, RT_SCOPE_UNIVERSE,
                           protocol, flow_flags, dst, src, dport, sport);

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 26d6ffb6d23cdf4fff4150cb5f43ec35f5081fd4..6c2af797f2f92b93cf4ea28d1d5deee4e725f757 100644 (file)
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1426,7 +1426,7 @@ found:
                            nh->nh_flags & RTNH_F_LINKDOWN &&
                            !(fib_flags & FIB_LOOKUP_IGNORE_LINKSTATE))
                                continue;
-                       if (!(flp->flowi4_flags & FLOWI_FLAG_VRFSRC)) {
+                       if (!(flp->flowi4_flags & FLOWI_FLAG_SKIP_NH_OIF)) {
                                if (flp->flowi4_oif &&
                                    flp->flowi4_oif != nh->nh_oif)
                                        continue;

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index c0a15e7f359fe54e4edcffca5d59acb418dad116..f7d1d5e19e955563178fcddb84c4ffe9abb66036 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1024,7 +1024,8 @@ int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
                if (netif_index_is_vrf(net, ipc.oif)) {
                        flowi4_init_output(fl4, ipc.oif, sk->sk_mark, tos,
                                           RT_SCOPE_UNIVERSE, sk->sk_protocol,
-                                          (flow_flags | FLOWI_FLAG_VRFSRC),
+                                          (flow_flags | FLOWI_FLAG_VRFSRC |
+                                           FLOWI_FLAG_SKIP_NH_OIF),
                                           faddr, saddr, dport,
                                           inet->inet_sport);
 

diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index bb919b28619fbfd7689d5479ca267ce03db89d71..c10a9ee684337782fa96b71302c0f05695711f36 100644 (file)
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -33,6 +33,8 @@ static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4,
        if (saddr)
                fl4->saddr = saddr->a4;
 
+       fl4->flowi4_flags = FLOWI_FLAG_SKIP_NH_OIF;
+
        rt = __ip_route_output_key(net, fl4);
        if (!IS_ERR(rt))
                return &rt->dst;