net/ipv6/udp: Fix ipv6 multicast socket filter regression

Commit <5cf3d46192fc> ("udp: Simplify__udp*_lib_mcast_deliver")
simplified the filter for incoming IPv6 multicast but removed
the check of the local socket address and the UDP destination
address.

This patch restores the filter to prevent sockets bound to a IPv6
multicast IP to receive other UDP traffic link unicast.

Signed-off-by: Henning Rogge <hrogge@gmail.com>
Fixes: 5cf3d46192fc ("udp: Simplify__udp*_lib_mcast_deliver")
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 3477c919fcc8eb534c3a438ab6d607a6215897f8..c2ec41617a35481d8b5b11dbae59884a0c16cbb3 100644 (file)
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -731,7 +731,9 @@ static bool __udp_v6_is_mcast_sock(struct net *net, struct sock *sk,
            (inet->inet_dport && inet->inet_dport != rmt_port) ||
            (!ipv6_addr_any(&sk->sk_v6_daddr) &&
                    !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
-           (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
+           (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) ||
+           (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
+                   !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr)))
                return false;
        if (!inet6_mc_check(sk, loc_addr, rmt_addr))
                return false;