Date:   Fri, 17 Mar 2023 21:54:15 +0000
From:   Bobby Eshleman <bobbyeshleman@gmail.com>
To:     Arseniy Krasnov <avkrasnov@sberdevices.ru>
Cc:     Stefan Hajnoczi <stefanha@redhat.com>,
        Stefano Garzarella <sgarzare@redhat.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Bobby Eshleman <bobby.eshleman@bytedance.com>,
        kvm@vger.kernel.org, virtualization@lists.linux-foundation.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel@sberdevices.ru, oxffffaa@gmail.com
Subject: Re: [RFC PATCH v1] virtio/vsock: check transport before skb
 allocation
Message-ID: <ZBThh0y3yVNwhlM5@bullseye>
References: <47a7dbf6-1c63-3338-5102-122766e6378d@sberdevices.ru>
MIME-Version: 1.0
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In-Reply-To: <47a7dbf6-1c63-3338-5102-122766e6378d@sberdevices.ru>
Precedence: bulk

On Fri, Mar 17, 2023 at 01:37:10PM +0300, Arseniy Krasnov wrote:
> Pointer to transport could be checked before allocation of skbuff, thus
> there is no need to free skbuff when this pointer is NULL.
> 
> Signed-off-by: Arseniy Krasnov <AVKrasnov@sberdevices.ru>
> ---
>  net/vmw_vsock/virtio_transport_common.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
> index cda587196475..607149259e8b 100644
> --- a/net/vmw_vsock/virtio_transport_common.c
> +++ b/net/vmw_vsock/virtio_transport_common.c
> @@ -867,6 +867,9 @@ static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
>  	if (le16_to_cpu(hdr->op) == VIRTIO_VSOCK_OP_RST)
>  		return 0;
>  
> +	if (!t)
> +		return -ENOTCONN;
> +
>  	reply = virtio_transport_alloc_skb(&info, 0,
>  					   le64_to_cpu(hdr->dst_cid),
>  					   le32_to_cpu(hdr->dst_port),
> @@ -875,11 +878,6 @@ static int virtio_transport_reset_no_sock(const struct virtio_transport *t,
>  	if (!reply)
>  		return -ENOMEM;
>  
> -	if (!t) {
> -		kfree_skb(reply);
> -		return -ENOTCONN;
> -	}
> -
>  	return t->send_pkt(reply);
>  }
>  
> -- 
> 2.25.1

LGTM.

Reviewed-by: Bobby Eshleman <bobby.eshleman@bytedance.com>