ipv6: udp: Do a route lookup and update during release_cb
This patch adds a release_cb for UDPv6. It does a route lookup
and updates sk->sk_dst_cache if it is needed. It picks up the
left-over job from ip6_sk_update_pmtu() if the sk was owned
by user during the pmtu update.
It takes a rcu_read_lock to protect the __sk_dst_get() operations
because another thread may do ip6_dst_store() without taking the
sk lock (e.g. sendmsg).
Fixes: 45e4fd26683c ("ipv6: Only create RTF_CACHE routes after encountering pmtu exception")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Reported-by: Wei Wang <weiwan@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 8125931..6bc5c66 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1539,6 +1539,7 @@
.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,