diff mbox series

[Openvpn-devel,ovpn-net] ovpn: fix incorrect use of rcu_access_pointer()

Message ID 20260722015638.1295-1-qingfang.deng@linux.dev
State New
Headers
Series [Openvpn-devel,ovpn-net] ovpn: fix incorrect use of rcu_access_pointer() |

Commit Message

Qingfang Deng July 22, 2026, 1:56 a.m. UTC 
  rcu_access_pointer() should only be used to test the value of a pointer,
not to dereference it. Use rcu_dereference() instead. No extra
rcu_read_lock() is needed here, as the spin_lock_bh() above marks an RCU
critical section.

Fixes: f6226ae7a0cd ("ovpn: introduce the ovpn_socket object")
Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev>
---
 drivers/net/ovpn/peer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Antonio Quartulli July 22, 2026, 8:21 a.m. UTC | #1 
Hi!

On 22/07/2026 03:56, Qingfang Deng wrote:
> rcu_access_pointer() should only be used to test the value of a pointer,
> not to dereference it. Use rcu_dereference() instead. No extra
> rcu_read_lock() is needed here, as the spin_lock_bh() above marks an RCU
> critical section.
> 
> Fixes: f6226ae7a0cd ("ovpn: introduce the ovpn_socket object")
> Signed-off-by: Qingfang Deng <qingfang.deng@linux.dev>
> ---
>   drivers/net/ovpn/peer.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
> index a09d61296425..8de737579112 100644
> --- a/drivers/net/ovpn/peer.c
> +++ b/drivers/net/ovpn/peer.c
> @@ -1164,7 +1164,7 @@ static void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
>   	}
>   
>   	if (sk) {
> -		ovpn_sock = rcu_access_pointer(peer->sock);
> +		ovpn_sock = rcu_dereference(peer->sock);

Sashiko says:

Using `rcu_dereference()` instead of `rcu_dereference_bh()` under 
`spin_lock_bh()` triggers a lockdep warning.
diff mbox series

Patch

diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index a09d61296425..8de737579112 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c
@@ -1164,7 +1164,7 @@  static void ovpn_peer_release_p2p(struct ovpn_priv *ovpn, struct sock *sk,
 	}
 
 	if (sk) {
-		ovpn_sock = rcu_access_pointer(peer->sock);
+		ovpn_sock = rcu_dereference(peer->sock);
 		if (!ovpn_sock || ovpn_sock->sk != sk) {
 			spin_unlock_bh(&ovpn->lock);
 			ovpn_peer_put(peer);