net/tcp: Fix socket lookups with SO_BINDTODEVICE

Similar to 69678bcd4d2d ("udp: fix SO_BINDTODEVICE"), TCP socket lookups
need to fail if dev_match is not true. Currently, a packet to a given port
can match a socket bound to device when it should not. In the VRF case,
this causes the lookup to hit a VRF socket and not a global socket
resulting in a response trying to go through the VRF when it should not.

Fixes: 3fa6f616a7a4d ("net: ipv4: add second dif to inet socket lookups")
Fixes: 4297a0ef08572 ("net: ipv6: add second dif to inet6 socket lookups")
Reported-by: Lou Berger <lberger@labn.net>
Diagnosed-by: Renato Westphal <renato@opensourcerouting.org>
Tested-by: Renato Westphal <renato@opensourcerouting.org>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 2febe26de6a1..595ad408dba0 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -113,9 +113,9 @@ static inline int compute_score(struct sock *sk, struct net *net,
                         bool dev_match = (sk->sk_bound_dev_if == dif ||
                                           sk->sk_bound_dev_if == sdif);
 
-                        if (exact_dif && !dev_match)
+                        if (!dev_match)
                                 return -1;
-                        if (sk->sk_bound_dev_if && dev_match)
+                        if (sk->sk_bound_dev_if)
                                 score++;
                 }
                 if (sk->sk_incoming_cpu == raw_smp_processor_id())