tcp: Save v4 address as v4-mapped-v6 in inet_bind2_bucket.v6_rcv_saddr.

In bhash2, IPv4/IPv6 addresses are saved in two union members,
which complicate address checks in inet_bind2_bucket_addr_match()
and inet_bind2_bucket_match_addr_any() considering uninitialised
memory and v4-mapped-v6 conflicts.

Let's simplify that by saving IPv4 address as v4-mapped-v6 address
and defining tb2.rcv_saddr as tb2.v6_rcv_saddr.s6_addr32[3].

Then, we can compare v6 address as is, and after checking v4-mapped-v6,
we can compare v4 address easily.  Also, we can remove tb2->family.

Note these functions will be further refactored in the next patch.

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

diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
index 3ecfeadbfa0694ad129bef20466de6b6c8b5adba..171cc235d0451f7597b7fd5b6ce3215e4a8e681c 100644 (file)
--- a/include/net/inet_hashtables.h
+++ b/include/net/inet_hashtables.h
@@ -96,14 +96,11 @@ struct inet_bind2_bucket {
        int                     l3mdev;
        unsigned short          port;
 #if IS_ENABLED(CONFIG_IPV6)
-       unsigned short          family;
-#endif
-       union {
-#if IS_ENABLED(CONFIG_IPV6)
-               struct in6_addr         v6_rcv_saddr;
+       struct in6_addr         v6_rcv_saddr;
+#define rcv_saddr              v6_rcv_saddr.s6_addr32[3]
+#else
+       __be32                  rcv_saddr;
 #endif
-               __be32                  rcv_saddr;
-       };
        /* Node in the bhash2 inet_bind_hashbucket chain */
        struct hlist_node       node;
        /* List of sockets hashed to this bucket */

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 78d38dd88aba4ab9e1cf34e3f422b121e41a4618..cf25ea21d770d4fe1b235bf2d1ec0088b4b0ff45 100644 (file)
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -784,11 +784,6 @@ static inline bool ipv6_addr_v4mapped(const struct in6_addr *a)
                                        cpu_to_be32(0x0000ffff))) == 0UL;
 }
 
-static inline bool ipv6_addr_v4mapped_any(const struct in6_addr *a)
-{
-       return ipv6_addr_v4mapped(a) && ipv4_is_zeronet(a->s6_addr32[3]);
-}
-
 static inline bool ipv6_addr_v4mapped_loopback(const struct in6_addr *a)
 {
        return ipv6_addr_v4mapped(a) && ipv4_is_loopback(a->s6_addr32[3]);

diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 896fcefc06c00bd2a093093abb3a4a9f3b3eef12..15594424e9f5afd05d49c21c5fd1d488961fa33e 100644 (file)
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -110,12 +110,13 @@ static void inet_bind2_bucket_init(struct inet_bind2_bucket *tb,
        tb->l3mdev    = l3mdev;
        tb->port      = port;
 #if IS_ENABLED(CONFIG_IPV6)
-       tb->family    = sk->sk_family;
        if (sk->sk_family == AF_INET6)
                tb->v6_rcv_saddr = sk->sk_v6_rcv_saddr;
        else
+               ipv6_addr_set_v4mapped(sk->sk_rcv_saddr, &tb->v6_rcv_saddr);
+#else
+       tb->rcv_saddr = sk->sk_rcv_saddr;
 #endif
-               tb->rcv_saddr = sk->sk_rcv_saddr;
        INIT_HLIST_HEAD(&tb->owners);
        INIT_HLIST_HEAD(&tb->deathrow);
        hlist_add_head(&tb->node, &head->chain);
@@ -149,17 +150,11 @@ static bool inet_bind2_bucket_addr_match(const struct inet_bind2_bucket *tb2,
                                         const struct sock *sk)
 {
 #if IS_ENABLED(CONFIG_IPV6)
-       if (sk->sk_family == AF_INET6) {
-               if (tb2->family == AF_INET6)
-                       return ipv6_addr_equal(&tb2->v6_rcv_saddr, &sk->sk_v6_rcv_saddr);
-
-               return ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr) &&
-                       sk->sk_v6_rcv_saddr.s6_addr32[3] == tb2->rcv_saddr;
-       }
+       if (sk->sk_family == AF_INET6)
+               return ipv6_addr_equal(&tb2->v6_rcv_saddr, &sk->sk_v6_rcv_saddr);
 
-       if (tb2->family == AF_INET6)
-               return ipv6_addr_v4mapped(&tb2->v6_rcv_saddr) &&
-                       tb2->v6_rcv_saddr.s6_addr32[3] == sk->sk_rcv_saddr;
+       if (!ipv6_addr_v4mapped(&tb2->v6_rcv_saddr))
+               return false;
 #endif
        return tb2->rcv_saddr == sk->sk_rcv_saddr;
 }
@@ -836,16 +831,21 @@ bool inet_bind2_bucket_match_addr_any(const struct inet_bind2_bucket *tb, const
 
 #if IS_ENABLED(CONFIG_IPV6)
        if (sk->sk_family == AF_INET6) {
-               if (tb->family == AF_INET6)
-                       return ipv6_addr_any(&tb->v6_rcv_saddr);
+               if (ipv6_addr_any(&tb->v6_rcv_saddr))
+                       return true;
+
+               if (!ipv6_addr_v4mapped(&tb->v6_rcv_saddr))
+                       return false;
 
                return ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr) &&
                        tb->rcv_saddr == 0;
        }
 
-       if (tb->family == AF_INET6)
-               return ipv6_addr_any(&tb->v6_rcv_saddr) ||
-                       ipv6_addr_v4mapped_any(&tb->v6_rcv_saddr);
+       if (ipv6_addr_any(&tb->v6_rcv_saddr))
+               return true;
+
+       if (!ipv6_addr_v4mapped(&tb->v6_rcv_saddr))
+               return false;
 #endif
        return tb->rcv_saddr == 0;
 }