[PATCH] nvmet-tcp: fix callback lock for TLS handshake

[Maurizio Lombardi]

On Fri Jul 4, 2025 at 4:44 PM CEST, Maurizio Lombardi wrote:
> When restoring the default socket callbacks during a
> TLS handshake, we need to acquire a write lock on sk_callback_lock.
> Previously, a read lock was used, which is insufficient for
> modifying sk_user_data and sk_data_ready.

I forgot the Fixes tag

Fixes: 675b453e0241 ("nvmet-tcp: enable TLS handshake upcall")

Maurizio

>
> Signed-off-by: Maurizio Lombardi <mlombard at redhat.com>
> ---
>  drivers/nvme/target/tcp.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
> index 688033b88d38..470bf37e5a63 100644
> --- a/drivers/nvme/target/tcp.c
> +++ b/drivers/nvme/target/tcp.c
> @@ -1928,10 +1928,10 @@ static void nvmet_tcp_alloc_queue(struct nvmet_tcp_port *port,
>  		struct sock *sk = queue->sock->sk;
>  
>  		/* Restore the default callbacks before starting upcall */
> -		read_lock_bh(&sk->sk_callback_lock);
> +		write_lock_bh(&sk->sk_callback_lock);
>  		sk->sk_user_data = NULL;
>  		sk->sk_data_ready = port->data_ready;
> -		read_unlock_bh(&sk->sk_callback_lock);
> +		write_unlock_bh(&sk->sk_callback_lock);
>  		if (!nvmet_tcp_try_peek_pdu(queue)) {
>  			if (!nvmet_tcp_tls_handshake(queue))
>  				return;