net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP

BugLink: https://bugs.launchpad.net/bugs/1715812
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.

The datagram protocols can use MSG_CONFIRM to confirm the
neighbour. When used with MSG_PROBE we do not reach the
code where neighbour is confirmed, so we have to do the
same slow lookup by using the dst_confirm_neigh() helper.
When MSG_PROBE is not used, ip_append_data/ip6_append_data
will set the skb flag dst_pending_confirm.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 0dec879f636f11b0ffda1cb5fd96a1754c59ead3)
Signed-off-by: Daniel Axtens <daniel.axtens@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Colin King <colin.king@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 8c85cad2b2afe24c6bd9d75c391340df53c6eacb..2b558a01c3a9e09608a173a6619d1ec93b190b3a 100644 (file)
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -889,6 +889,9 @@ static inline int ip_ufo_append_data(struct sock *sk,
 
                skb->csum = 0;
 
+               if (flags & MSG_CONFIRM)
+                       skb_set_dst_pending_confirm(skb, 1);
+
                __skb_queue_tail(queue, skb);
        } else if (skb_is_gso(skb)) {
                goto append;
@@ -1091,6 +1094,9 @@ alloc_new_skb:
                        exthdrlen = 0;
                        csummode = CHECKSUM_NONE;
 
+                       if ((flags & MSG_CONFIRM) && !skb_prev)
+                               skb_set_dst_pending_confirm(skb, 1);
+
                        /*
                         * Put the packet on the pending queue.
                         */

diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c
index 51e2f3c5e954d81b236cfffc034cc920cdb07319..4f2d94c5f91ffdc9ea777f9332d157e95eade88b 100644 (file)
--- a/net/ipv4/ping.c
+++ b/net/ipv4/ping.c
@@ -851,7 +851,8 @@ out:
        return err;
 
 do_confirm:
-       dst_confirm(&rt->dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(&rt->dst, &fl4.daddr);
        if (!(msg->msg_flags & MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 259fbcd8c479c57e48c8a0c44916b1b051571c61..43b0297ed980ce939f6a63170fddd8fd9c5d692f 100644 (file)
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -386,6 +386,9 @@ static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
 
        sock_tx_timestamp(sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);
 
+       if (flags & MSG_CONFIRM)
+               skb_set_dst_pending_confirm(skb, 1);
+
        skb->transport_header = skb->network_header;
        err = -EFAULT;
        if (memcpy_from_msg(iph, msg, length))
@@ -669,7 +672,8 @@ out:
        return len;
 
 do_confirm:
-       dst_confirm(&rt->dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(&rt->dst, &fl4.daddr);
        if (!(msg->msg_flags & MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 2d20e23ea42053308dd545429f62fb6117b9f733..8a75840c5d8408f59dba5d56561dd8430079c9bb 100644 (file)
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1113,7 +1113,8 @@ out:
        return err;
 
 do_confirm:
-       dst_confirm(&rt->dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(&rt->dst, &fl4->daddr);
        if (!(msg->msg_flags&MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 7ceac3b8694a81775870d8604b81f9acc2bb09f7..d50322b51fa7c618d6952c9521d286ed9add5664 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1158,6 +1158,9 @@ static inline int ip6_ufo_append_data(struct sock *sk,
                skb->protocol = htons(ETH_P_IPV6);
                skb->csum = 0;
 
+               if (flags & MSG_CONFIRM)
+                       skb_set_dst_pending_confirm(skb, 1);
+
                __skb_queue_tail(queue, skb);
        } else if (skb_is_gso(skb)) {
                goto append;
@@ -1532,6 +1535,9 @@ alloc_new_skb:
                        exthdrlen = 0;
                        dst_exthdrlen = 0;
 
+                       if ((flags & MSG_CONFIRM) && !skb_prev)
+                               skb_set_dst_pending_confirm(skb, 1);
+
                        /*
                         * Put the packet on the pending queue
                         */

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 6006b3281a2e2a77b828414e4b677bc981906b8f..1f992d9e261d8b75226659a4cead95f8dc04dc4f 100644 (file)
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -656,6 +656,9 @@ static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
 
        skb->ip_summed = CHECKSUM_NONE;
 
+       if (flags & MSG_CONFIRM)
+               skb_set_dst_pending_confirm(skb, 1);
+
        skb->transport_header = skb->network_header;
        err = memcpy_from_msg(iph, msg, length);
        if (err)
@@ -936,7 +939,8 @@ out:
        txopt_put(opt_to_free);
        return err < 0 ? err : len;
 do_confirm:
-       dst_confirm(dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(dst, &fl6.daddr);
        if (!(msg->msg_flags & MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 9737526aefdf7a7e387f60dfbc127936701aa5ef..d319256db79adbe5776b83424df5693c613f624b 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1375,6 +1375,7 @@ static bool rt6_cache_allowed_for_pmtu(const struct rt6_info *rt)
 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
                                 const struct ipv6hdr *iph, u32 mtu)
 {
+       const struct in6_addr *daddr, *saddr;
        struct rt6_info *rt6 = (struct rt6_info *)dst;
 
        if (rt6->rt6i_flags & RTF_LOCAL)
@@ -1383,26 +1384,26 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
        if (dst_metric_locked(dst, RTAX_MTU))
                return;
 
-       dst_confirm(dst);
+       if (iph) {
+               daddr = &iph->daddr;
+               saddr = &iph->saddr;
+       } else if (sk) {
+               daddr = &sk->sk_v6_daddr;
+               saddr = &inet6_sk(sk)->saddr;
+       } else {
+               daddr = NULL;
+               saddr = NULL;
+       }
+       dst_confirm_neigh(dst, daddr);
        mtu = max_t(u32, mtu, IPV6_MIN_MTU);
        if (mtu >= dst_mtu(dst))
                return;
 
        if (!rt6_cache_allowed_for_pmtu(rt6)) {
                rt6_do_update_pmtu(rt6, mtu);
-       } else {
-               const struct in6_addr *daddr, *saddr;
+       } else if (daddr) {
                struct rt6_info *nrt6;
 
-               if (iph) {
-                       daddr = &iph->daddr;
-                       saddr = &iph->saddr;
-               } else if (sk) {
-                       daddr = &sk->sk_v6_daddr;
-                       saddr = &inet6_sk(sk)->saddr;
-               } else {
-                       return;
-               }
                nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
                if (nrt6) {
                        rt6_do_update_pmtu(nrt6, mtu);
@@ -2278,7 +2279,7 @@ static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_bu
         * Look, redirects are sent only in response to data packets,
         * so that this nexthop apparently is reachable. --ANK
         */
-       dst_confirm(&rt->dst);
+       dst_confirm_neigh(&rt->dst, &ipv6_hdr(skb)->saddr);
 
        neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
        if (!neigh)

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 0770f95f5e1c4b07d0cbb568f230456b234ca07b..7b01ee260f5678745b89455e181b427b84822bf6 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1299,7 +1299,8 @@ out:
        return err;
 
 do_confirm:
-       dst_confirm(dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(dst, &fl6.daddr);
        if (!(msg->msg_flags&MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;

diff --git a/net/l2tp/l2tp_ip6.c b/net/l2tp/l2tp_ip6.c
index 4e4fa1538cbbaf37561f79bd184e5823a8648ced..9f7a516ca808328a2016a89faf74324e79e764da 100644 (file)
--- a/net/l2tp/l2tp_ip6.c
+++ b/net/l2tp/l2tp_ip6.c
@@ -651,7 +651,8 @@ out:
        return err < 0 ? err : len;
 
 do_confirm:
-       dst_confirm(dst);
+       if (msg->msg_flags & MSG_PROBE)
+               dst_confirm_neigh(dst, &fl6.daddr);
        if (!(msg->msg_flags & MSG_PROBE) || len)
                goto back_from_confirm;
        err = 0;