From 78556423b52e9862e34075eef693b655721cbe99 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Fri, 8 Sep 2017 09:00:00 +0200 Subject: [PATCH] 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 Fixes: 5110effee8fd ("net: Do delayed neigh confirmation.") Fixes: f2bb4bedf35d ("ipv4: Cache output routes in fib_info nexthops.") Signed-off-by: Julian Anastasov Acked-by: Eric Dumazet Signed-off-by: David S. Miller (cherry picked from commit 0dec879f636f11b0ffda1cb5fd96a1754c59ead3) Signed-off-by: Daniel Axtens Acked-by: Stefan Bader Acked-by: Colin King Signed-off-by: Stefan Bader --- net/ipv4/ip_output.c | 6 ++++++ net/ipv4/ping.c | 3 ++- net/ipv4/raw.c | 6 +++++- net/ipv4/udp.c | 3 ++- net/ipv6/ip6_output.c | 6 ++++++ net/ipv6/raw.c | 6 +++++- net/ipv6/route.c | 27 ++++++++++++++------------- net/ipv6/udp.c | 3 ++- net/l2tp/l2tp_ip6.c | 3 ++- 9 files changed, 44 insertions(+), 19 deletions(-) diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 8c85cad2b2af..2b558a01c3a9 100644 --- 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 51e2f3c5e954..4f2d94c5f91f 100644 --- 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 259fbcd8c479..43b0297ed980 100644 --- 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 2d20e23ea420..8a75840c5d84 100644 --- 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 7ceac3b8694a..d50322b51fa7 100644 --- 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 6006b3281a2e..1f992d9e261d 100644 --- 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 9737526aefdf..d319256db79a 100644 --- 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 0770f95f5e1c..7b01ee260f56 100644 --- 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 4e4fa1538cbb..9f7a516ca808 100644 --- 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; -- 2.39.2