virtio/vsock: check transport before skb allocation

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>
Reviewed-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Link: https://lore.kernel.org/r/08d61bef-0c11-c7f9-9266-cb2109070314@sberdevices.ru
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 6564192..957cdc0 100644 (file)
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -850,6 +850,9 @@ 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),
@@ -858,11 +861,6 @@ 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);
 }