[PATCH 5.10 259/545] ipv6: add READ_ONCE(sk->sk_bound_dev_if) in INET6_MATCH()

Greg Kroah-Hartman
2022-08-19T16:19:14Z

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 5d368f03280d3678433a7f119efe15dfbbb87bc8 ]

INET6_MATCH() runs without holding a lock on the socket.

We probably need to annotate most reads.

This patch makes INET6_MATCH() an inline function
to ease our changes.

v2: inline function only defined if IS_ENABLED(CONFIG_IPV6)
Change the name to inet6_match(), this is no longer a macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/inet6_hashtables.h | 28 +++++++++++++++++++---------
net/ipv4/inet_hashtables.c | 2 +-
net/ipv6/inet6_hashtables.c | 6 +++---
net/ipv6/udp.c | 2 +-
4 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/include/net/inet6_hashtables.h b/include/net/inet6_hashtables.h
index 81b965953036..f259e1ae14ba 100644
--- a/include/net/inet6_hashtables.h
+++ b/include/net/inet6_hashtables.h
@@ -103,15 +103,25 @@ struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
const int dif);

int inet6_hash(struct sock *sk);
-#endif /* IS_ENABLED(CONFIG_IPV6) */

-#define INET6_MATCH(__sk, __net, __saddr, __daddr, __ports, __dif, __sdif) \
- (((__sk)->sk_portpair == (__ports)) && \
- ((__sk)->sk_family == AF_INET6) && \
- ipv6_addr_equal(&(__sk)->sk_v6_daddr, (__saddr)) && \
- ipv6_addr_equal(&(__sk)->sk_v6_rcv_saddr, (__daddr)) && \
- (((__sk)->sk_bound_dev_if == (__dif)) || \
- ((__sk)->sk_bound_dev_if == (__sdif))) && \
- net_eq(sock_net(__sk), (__net)))
+static inline bool inet6_match(struct net *net, const struct sock *sk,
+ const struct in6_addr *saddr,
+ const struct in6_addr *daddr,
+ const __portpair ports,
+ const int dif, const int sdif)
+{
+ int bound_dev_if;
+
+ if (!net_eq(sock_net(sk), net) ||
+ sk->sk_family != AF_INET6 ||
+ sk->sk_portpair != ports ||
+ !ipv6_addr_equal(&sk->sk_v6_daddr, saddr) ||
+ !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
+ return false;
+
+ bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
+ return bound_dev_if == dif || bound_dev_if == sdif;
+}
+#endif /* IS_ENABLED(CONFIG_IPV6) */

#endif /* _INET6_HASHTABLES_H */
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 7dbe80e30b9d..feb7f072f2b2 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -536,7 +536,7 @@ static bool inet_ehash_lookup_by_sk(struct sock *sk,
}
#if IS_ENABLED(CONFIG_IPV6)
else if (sk->sk_family == AF_INET6) {
- if (unlikely(INET6_MATCH(esk, net,
+ if (unlikely(inet6_match(net, esk,
&sk->sk_v6_daddr,
&sk->sk_v6_rcv_saddr,
ports, dif, sdif))) {
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 40203255ed88..b4a5e01e1201 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -71,12 +71,12 @@ struct sock *__inet6_lookup_established(struct net *net,
sk_nulls_for_each_rcu(sk, node, &head->chain) {
if (sk->sk_hash != hash)
continue;
- if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))
+ if (!inet6_match(net, sk, saddr, daddr, ports, dif, sdif))
continue;
if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
goto out;

- if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))) {
+ if (unlikely(!inet6_match(net, sk, saddr, daddr, ports, dif, sdif))) {
sock_gen_put(sk);
goto begin;
}
@@ -269,7 +269,7 @@ static int __inet6_check_established(struct inet_timewait_death_row *death_row,
if (sk2->sk_hash != hash)
continue;

- if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports,
+ if (likely(inet6_match(net, sk2, saddr, daddr, ports,
dif, sdif))) {
if (sk2->sk_state == TCP_TIME_WAIT) {
tw = inet_twsk(sk2);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 7745d8a40209..4e90e5a52945 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -1019,7 +1019,7 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net,

udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
if (sk->sk_state == TCP_ESTABLISHED &&
- INET6_MATCH(sk, net, rmt_addr, loc_addr, ports, dif, sdif))
+ inet6_match(net, sk, rmt_addr, loc_addr, ports, dif, sdif))
return sk;
/* Only check first socket in chain */
break;
--
2.35.1