net: ipv6: reset daddr and dport in sk if connect() fails

In __ip6_datagram_connect(), reset sk->sk_v6_daddr and inet->dport if
error occurs.
In udp_v6_early_demux(), check for sk_state to make sure it is in
TCP_ESTABLISHED state.
Together, it makes sure unconnected UDP socket won't be considered as a
valid candidate for early demux.

v3: add TCP_ESTABLISHED state check in udp_v6_early_demux()
v2: fix compilation error

CRs-Fixed: 2122802
Change-Id: Ifa9c2ddfaa5b51d4082b7b1dd8a5d03b3c290705
Fixes: 5425077d73e0 ("net: ipv6: Add early demux handler for UDP unicast")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Git-commit: 85cb73ff9b74785a7fc752875d7f0fe17ca3ea7c
Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index c2b4dec..cdeb6b2 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -883,7 +883,8 @@
 	struct sock *sk;
 
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
-		if (INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif))
+		if (sk->sk_state == TCP_ESTABLISHED &&
+		    INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif))
 			return sk;
 		/* Only check first socket in chain */
 		break;