From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-44.mimecast.com (us-smtp-delivery-44.mimecast.com [205.139.111.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F8881CA94 for ; Wed, 8 May 2024 17:11:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.139.111.44 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715188269; cv=none; b=nX6WDrRKlAT9Wub5ebIt/hfgJxa4I80FH0WU9Y6ZF4THiU1EXrWMioIhO4YKsSkttRtmsSIW3cmNip2oyw9Iqrqa4eAgleuBR0vNQspufszjNRfWaiEMVJ7f9RU1we8AZb5KiZlIMEeWB/a7HSErKx19vdmirxhLpZ7yMu8AXk8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715188269; c=relaxed/simple; bh=E0FiSFliG8Bji2GDUslydM4/J8NGsMJGoeMJmTCNhb4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: In-Reply-To:Content-Type:Content-Disposition; b=i+n8Kk7Z3k59FLpaC0th6h06/vexJzdeOEReDo+3pPnEbpyaDvcTjtsqALNy2yDLt+IkHjx0WzNcPeNinKhTs6M3uPHcZ4wMff1jA89k/dyzfn+sVMmFBD3P1F4NYrj7tDGNJfbmbDnfWzR5D5qD18H4sBqClPXdK+pLP3P02Hs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=queasysnail.net; spf=none smtp.mailfrom=queasysnail.net; arc=none smtp.client-ip=205.139.111.44 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=queasysnail.net Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=queasysnail.net Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-60-jXVq_McfOAW9h6O9n1-3kg-1; Wed, 08 May 2024 13:10:59 -0400 X-MC-Unique: jXVq_McfOAW9h6O9n1-3kg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.rdu2.redhat.com [10.11.54.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8FCA5101A551; Wed, 8 May 2024 17:10:58 +0000 (UTC) Received: from hog (unknown [10.39.193.137]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5FC3A3C25; Wed, 8 May 2024 17:10:57 +0000 (UTC) Date: Wed, 8 May 2024 19:10:56 +0200 From: Sabrina Dubroca To: Antonio Quartulli Cc: netdev@vger.kernel.org, Jakub Kicinski , Sergey Ryazanov , Paolo Abeni , Eric Dumazet , Andrew Lunn , Esben Haabendal Subject: Re: [PATCH net-next v3 08/24] ovpn: introduce the ovpn_socket object Message-ID: References: <20240506011637.27272-1-antonio@openvpn.net> <20240506011637.27272-9-antonio@openvpn.net> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <20240506011637.27272-9-antonio@openvpn.net> X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: queasysnail.net Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 2024-05-06, 03:16:21 +0200, Antonio Quartulli wrote: > This specific structure is used in the ovpn kernel module > to wrap and carry around a standard kernel socket. >=20 > ovpn takes ownership of passed sockets and therefore an ovpn > specific objects is attathced to them for status tracking typos: object attached > diff --git a/drivers/net/ovpn/socket.c b/drivers/net/ovpn/socket.c > new file mode 100644 > index 000000000000..a4a4d69162f0 > --- /dev/null > +++ b/drivers/net/ovpn/socket.c [...] > + > +/* Finalize release of socket, called after RCU grace period */ kref_put seems to call ovpn_socket_release_kref without waiting, and then that calls ovpn_socket_detach immediately as well. Am I missing something? > +static void ovpn_socket_detach(struct socket *sock) > +{ > +=09if (!sock) > +=09=09return; > + > +=09sockfd_put(sock); > +} [...] > + > +/* Finalize release of socket, called after RCU grace period */ Did that comment get misplaced? It doesn't match the code. > +static int ovpn_socket_attach(struct socket *sock, struct ovpn_peer *pee= r) > +{ > +=09int ret =3D -EOPNOTSUPP; > + > +=09if (!sock || !peer) > +=09=09return -EINVAL; > + > +=09if (sock->sk->sk_protocol =3D=3D IPPROTO_UDP) > +=09=09ret =3D ovpn_udp_socket_attach(sock, peer->ovpn); > + > +=09return ret; > +} > diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c > new file mode 100644 > index 000000000000..4b7d96a13df0 > --- /dev/null > +++ b/drivers/net/ovpn/udp.c [...] > + > +int ovpn_udp_socket_attach(struct socket *sock, struct ovpn_struct *ovpn= ) > +{ > +=09struct ovpn_socket *old_data; > + > +=09/* sanity check */ > +=09if (sock->sk->sk_protocol !=3D IPPROTO_UDP) { > +=09=09netdev_err(ovpn->dev, "%s: expected UDP socket\n", __func__); Maybe use DEBUG_NET_WARN_ON_ONCE here since it's never expected to actually happen? That would help track down (in test/debug setups) how we ended up here. > +=09=09return -EINVAL; > +=09} > + > +=09/* make sure no pre-existing encapsulation handler exists */ > +=09rcu_read_lock(); > +=09old_data =3D rcu_dereference_sk_user_data(sock->sk); > +=09rcu_read_unlock(); > +=09if (old_data) { > +=09=09if (old_data->ovpn =3D=3D ovpn) { You should stay under rcu_read_unlock if you access old_data's fields. > +=09=09=09netdev_dbg(ovpn->dev, > +=09=09=09=09 "%s: provided socket already owned by this interface\n", > +=09=09=09=09 __func__); > +=09=09=09return -EALREADY; > +=09=09} > + > +=09=09netdev_err(ovpn->dev, "%s: provided socket already taken by other = user\n", > +=09=09=09 __func__); > +=09=09return -EBUSY; > +=09} > + > +=09return 0; > +} --=20 Sabrina