tcp: Use bhash2 for v4-mapped-v6 non-wildcard address.
authorKuniyuki Iwashima <kuniyu@amazon.com>
Tue, 19 Dec 2023 00:18:22 +0000 (09:18 +0900)
committerDavid S. Miller <davem@davemloft.net>
Fri, 22 Dec 2023 22:15:34 +0000 (22:15 +0000)
While checking port availability in bind() or listen(), we used only
bhash for all v4-mapped-v6 addresses.  But there is no good reason not
to use bhash2 for v4-mapped-v6 non-wildcard addresses.

Let's do it by returning true in inet_use_bhash2_on_bind().  Then, we
also need to add a test in inet_bind2_bucket_match_addr_any() so that
::ffff:X.X.X.X will match with 0.0.0.0.

Note that sk->sk_rcv_saddr is initialised for v4-mapped-v6 sk in
__inet6_bind().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv4/inet_connection_sock.c
net/ipv4/inet_hashtables.c

index bd325b029dd12c9fad754ded266ae232ee7ec260..d48255875f605865982c89a9766bcda60470666d 100644 (file)
@@ -159,8 +159,11 @@ static bool inet_use_bhash2_on_bind(const struct sock *sk)
        if (sk->sk_family == AF_INET6) {
                int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
 
-               return addr_type != IPV6_ADDR_ANY &&
-                       addr_type != IPV6_ADDR_MAPPED;
+               if (addr_type == IPV6_ADDR_ANY)
+                       return false;
+
+               if (addr_type != IPV6_ADDR_MAPPED)
+                       return true;
        }
 #endif
        return sk->sk_rcv_saddr != htonl(INADDR_ANY);
index 9ff201bc4e6d2da04735e8c160d446602e0adde1..7e8dbc5cc31765149e8477b40a2fd4820df44828 100644 (file)
@@ -841,7 +841,8 @@ bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const
                        return ipv6_addr_any(&tb->v6_rcv_saddr) ||
                                ipv6_addr_v4mapped_any(&tb->v6_rcv_saddr);
 
-               return false;
+               return ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr) &&
+                       tb->rcv_saddr == 0;
        }
 
        if (sk->sk_family == AF_INET6)