This is a note to let you know that I've just added the patch titled
net: use unrcu_pointer() helper
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-use-unrcu_pointer-helper.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 5f441cdfd55a7c569562f1dfd753b4b1f5343166
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Tue Jun 4 11:16:03 2024 +0000
net: use unrcu_pointer() helper
[ Upstream commit b4cb4a1391dcdc640c4ade003aaf0ee19cc8d509 ]
Toke mentioned unrcu_pointer() existence, allowing
to remove some of the ugly casts we have when using
xchg() for rcu protected pointers.
Also make inet_rcv_compat const.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
Reviewed-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240604111603.45871-1-edumazet@xxxxxxxxxx
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Stable-dep-of: eb02688c5c45 ("ipv6: release nexthop on device removal")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/net/sock.h b/include/net/sock.h
index 1b39b62d44e24..0a06c997b45be 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -2246,7 +2246,7 @@ sk_dst_set(struct sock *sk, struct dst_entry *dst)
sk_tx_queue_clear(sk);
WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
- old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
+ old_dst = unrcu_pointer(xchg(&sk->sk_dst_cache, RCU_INITIALIZER(dst)));
dst_release(old_dst);
}
diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c
index 4fcbdd71c59fa..e0654e3a92861 100644
--- a/net/core/gen_estimator.c
+++ b/net/core/gen_estimator.c
@@ -206,7 +206,7 @@ void gen_kill_estimator(struct net_rate_estimator __rcu **rate_est)
{
struct net_rate_estimator *est;
- est = xchg((__force struct net_rate_estimator **)rate_est, NULL);
+ est = unrcu_pointer(xchg(rate_est, NULL));
if (est) {
del_timer_sync(&est->timer);
kfree_rcu(est, rcu);
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c
index d36beb9a9a928..17972558f54a0 100644
--- a/net/core/sock_diag.c
+++ b/net/core/sock_diag.c
@@ -18,7 +18,7 @@
static const struct sock_diag_handler __rcu *sock_diag_handlers[AF_MAX];
-static struct sock_diag_inet_compat __rcu *inet_rcv_compat;
+static const struct sock_diag_inet_compat __rcu *inet_rcv_compat;
static struct workqueue_struct *broadcast_wq;
@@ -184,8 +184,7 @@ void sock_diag_broadcast_destroy(struct sock *sk)
void sock_diag_register_inet_compat(const struct sock_diag_inet_compat *ptr)
{
- xchg((__force const struct sock_diag_inet_compat **)&inet_rcv_compat,
- ptr);
+ xchg(&inet_rcv_compat, RCU_INITIALIZER(ptr));
}
EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat);
@@ -193,8 +192,7 @@ void sock_diag_unregister_inet_compat(const struct sock_diag_inet_compat *ptr)
{
const struct sock_diag_inet_compat *old;
- old = xchg((__force const struct sock_diag_inet_compat **)&inet_rcv_compat,
- NULL);
+ old = unrcu_pointer(xchg(&inet_rcv_compat, NULL));
WARN_ON_ONCE(old != ptr);
}
EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat);
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 2b56cabe4da98..fd139daf9dfb3 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1955,7 +1955,7 @@ int cipso_v4_req_setattr(struct request_sock *req,
buf = NULL;
req_inet = inet_rsk(req);
- opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt);
+ opt = unrcu_pointer(xchg(&req_inet->ireq_opt, RCU_INITIALIZER(opt)));
if (opt)
kfree_rcu(opt, rcu);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index cb79919323a62..e27a9a9bb1623 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -3184,7 +3184,7 @@ int tcp_disconnect(struct sock *sk, int flags)
icsk->icsk_ack.rcv_mss = TCP_MIN_MSS;
memset(&tp->rx_opt, 0, sizeof(tp->rx_opt));
__sk_dst_reset(sk);
- dst_release(xchg((__force struct dst_entry **)&sk->sk_rx_dst, NULL));
+ dst_release(unrcu_pointer(xchg(&sk->sk_rx_dst, NULL)));
tcp_saved_syn_free(tp);
tp->compressed_ack = 0;
tp->segs_in = 0;
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c
index 85e4953f11821..d0b7ded591bd4 100644
--- a/net/ipv4/tcp_fastopen.c
+++ b/net/ipv4/tcp_fastopen.c
@@ -49,7 +49,7 @@ void tcp_fastopen_ctx_destroy(struct net *net)
{
struct tcp_fastopen_context *ctxt;
- ctxt = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, NULL);
+ ctxt = unrcu_pointer(xchg(&net->ipv4.tcp_fastopen_ctx, NULL));
if (ctxt)
call_rcu(&ctxt->rcu, tcp_fastopen_ctx_free);
@@ -80,9 +80,10 @@ int tcp_fastopen_reset_cipher(struct net *net, struct sock *sk,
if (sk) {
q = &inet_csk(sk)->icsk_accept_queue.fastopenq;
- octx = xchg((__force struct tcp_fastopen_context **)&q->ctx, ctx);
+ octx = unrcu_pointer(xchg(&q->ctx, RCU_INITIALIZER(ctx)));
} else {
- octx = xchg((__force struct tcp_fastopen_context **)&net->ipv4.tcp_fastopen_ctx, ctx);
+ octx = unrcu_pointer(xchg(&net->ipv4.tcp_fastopen_ctx,
+ RCU_INITIALIZER(ctx)));
}
if (octx)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 53267566808c1..3f9c4b74fdc0c 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -2252,7 +2252,7 @@ bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
struct dst_entry *old;
if (dst_hold_safe(dst)) {
- old = xchg((__force struct dst_entry **)&sk->sk_rx_dst, dst);
+ old = unrcu_pointer(xchg(&sk->sk_rx_dst, RCU_INITIALIZER(dst)));
dst_release(old);
return old != dst;
}
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 62247621cea52..ea16c40cfb211 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -513,7 +513,7 @@ void inet6_destroy_sock(struct sock *sk)
/* Free tx options */
- opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
+ opt = unrcu_pointer(xchg(&np->opt, NULL));
if (opt) {
atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
txopt_put(opt);
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 1123594ad2be7..0b45ef8b7ee21 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -983,7 +983,7 @@ static void __fib6_drop_pcpu_from(struct fib6_nh *fib6_nh,
if (pcpu_rt && rcu_access_pointer(pcpu_rt->from) == match) {
struct fib6_info *from;
- from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
+ from = unrcu_pointer(xchg(&pcpu_rt->from, NULL));
fib6_info_release(from);
}
}
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index 532f4478c8840..2924aa45adbc5 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -111,8 +111,7 @@ struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
}
}
- opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
- opt);
+ opt = unrcu_pointer(xchg(&inet6_sk(sk)->opt, RCU_INITIALIZER(opt)));
sk_dst_reset(sk);
return opt;
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 6a227edf8a8aa..10e7517d126d9 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -369,7 +369,7 @@ static void ip6_dst_destroy(struct dst_entry *dst)
in6_dev_put(idev);
}
- from = xchg((__force struct fib6_info **)&rt->from, NULL);
+ from = unrcu_pointer(xchg(&rt->from, NULL));
fib6_info_release(from);
}
@@ -1432,7 +1432,7 @@ static struct rt6_info *rt6_make_pcpu_route(struct net *net,
if (res->f6i->fib6_destroying) {
struct fib6_info *from;
- from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL);
+ from = unrcu_pointer(xchg(&pcpu_rt->from, NULL));
fib6_info_release(from);
}
@@ -1461,7 +1461,7 @@ static void rt6_remove_exception(struct rt6_exception_bucket *bucket,
/* purge completely the exception to allow releasing the held resources:
* some [sk] cache may keep the dst around for unlimited time
*/
- from = xchg((__force struct fib6_info **)&rt6_ex->rt6i->from, NULL);
+ from = unrcu_pointer(xchg(&rt6_ex->rt6i->from, NULL));
fib6_info_release(from);
dst_dev_put(&rt6_ex->rt6i->dst);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 05bd1e9bca36a..b75e22756c4b0 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -61,7 +61,7 @@ static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
{
struct tc_cookie *old;
- old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
+ old = unrcu_pointer(xchg(old_cookie, RCU_INITIALIZER(new_cookie)));
if (old)
call_rcu(&old->rcu, tcf_free_cookie_rcu);
}
