Similar to commit 8141ed9fcedb, this implements a socket
release callback function to check if an IPv6 socket cached
route got invalid during the time we owned the socket.
The function is used from udp, raw sockets.
Cc: Steffen Klassert <steffen.klass...@secunet.com>
Cc: Martin KaFai Lau <ka...@fb.com>
Cc: Hannes Frederic Sowa <han...@stressinduktion.org>
Cc: Steffen Klassert <steffen.klass...@secunet.com>
Cc: Julian Anastasov <j...@ssi.bg>
Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
---
include/net/ipv6.h | 1 +
net/ipv6/datagram.c | 40 ++++++++++++++++++++++++++++++++++++++++
net/ipv6/raw.c | 1 +
net/ipv6/udp.c | 1 +
4 files changed, 43 insertions(+)
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index d0aeb97..890456d 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -959,6 +959,7 @@ int compat_ipv6_getsockopt(struct sock *sk, int level, int
optname,
int ip6_datagram_connect(struct sock *sk, struct sockaddr *addr, int addr_len);
int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *addr,
int addr_len);
+void ip6_datagram_release_cb(struct sock *sk);
int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
int *addr_len);
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 4281621..a743caa 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -231,6 +231,46 @@ int ip6_datagram_connect_v6_only(struct sock *sk, struct
sockaddr *uaddr,
}
EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
+void ip6_datagram_release_cb(struct sock *sk)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct in6_addr *final_p, final;
+ struct ipv6_txoptions *opt;
+ struct dst_entry *dst;
+ struct flowi6 fl6;
+ struct rtable *rt;
+
+ rcu_read_lock();
+
+ dst = __sk_dst_get(sk);
+ if (!dst || !dst->obsolete || dst->ops->check(dst, 0)) {
+ rcu_read_unlock();
+ return;
+ }
+
+ memset(&fl6, 0, sizeof(fl6));
+ fl6.flowi6_proto = sk->sk_protocol;
+ fl6.daddr = sk->sk_v6_daddr;
+ fl6.saddr = np->saddr;
+ fl6.flowi6_oif = sk->sk_bound_dev_if;
+ fl6.flowi6_mark = sk->sk_mark;
+ fl6.fl6_dport = inet->inet_dport;
+ fl6.fl6_sport = inet->inet_sport;
+
+ rcu_read_lock();
+ opt = rcu_dereference(np->opt);
+ final_p = fl6_update_dst(&fl6, opt, &final);
+ rcu_read_unlock();
+
+ dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+ dst = !IS_ERR(rt) ? &rt->dst : NULL;
+ sk_dst_set(sk, dst);
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
+
void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload)
{
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index fa59dd7..4319e65 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -1235,6 +1235,7 @@ struct proto rawv6_prot = {
.recvmsg = rawv6_recvmsg,
.bind = rawv6_bind,
.backlog_rcv = rawv6_rcv_skb,
+ .release_cb = ip6_datagram_release_cb,
.hash = raw_hash_sk,
.unhash = raw_unhash_sk,
.obj_size = sizeof(struct raw6_sock),
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index fd25e44..0fdaf8f 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1539,6 +1539,7 @@ struct proto udpv6_prot = {
.sendmsg = udpv6_sendmsg,
.recvmsg = udpv6_recvmsg,
.backlog_rcv = __udpv6_queue_rcv_skb,
+ .release_cb = ip6_datagram_release_cb,
.hash = udp_lib_hash,
.unhash = udp_lib_unhash,
.rehash = udp_v6_rehash,
--
2.1.0
