From: Jason Wang <jasowang@redhat.com> stable inclusion from stable-v5.10.129 commit f7b8fb4584456c5cdc3400b14d69d28a0c4a701a category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5YNDQ Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 50c0ada627f56c92f5953a8bf9158b045ad026a1 upstream. We currently call virtio_device_ready() after netdev registration. Since ndo_open() can be called immediately after register_netdev, this means there exists a race between ndo_open() and virtio_device_ready(): the driver may start to use the device before DRIVER_OK which violates the spec. Fix this by switching to use register_netdevice() and protect the virtio_device_ready() with rtnl_lock() to make sure ndo_open() can only be called after virtio_device_ready(). Fixes: 4baf1e33d0842 ("virtio_net: enable VQs early") Signed-off-by: Jason Wang <jasowang@redhat.com> Message-Id: <20220617072949.30734-1-jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- drivers/net/virtio_net.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index c75e4a1d0544..3bcff03c22f1 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -3177,14 +3177,20 @@ static int virtnet_probe(struct virtio_device *vdev) } } - err = register_netdev(dev); + /* serialize netdev register + virtio_device_ready() with ndo_open() */ + rtnl_lock(); + + err = register_netdevice(dev); if (err) { pr_debug("virtio_net: registering device failed\n"); + rtnl_unlock(); goto free_failover; } virtio_device_ready(vdev); + rtnl_unlock(); + err = virtnet_cpu_notif_add(vi); if (err) { pr_debug("virtio_net: registering cpu notifier failed\n"); -- 2.20.1