From: Jason Wang jasowang@redhat.com
stable inclusion from stable-v5.10.129 commit 653bdcd833b7505987bbda852144c8b6a4b2ab3a 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=...
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commit 11a37eb66812ce6a06b79223ad530eb0e1d7294d upstream.
We currently depend on probe() calling virtio_device_ready() - which happens 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 (e.g. TX) 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: 0d2e1a2926b18 ("caif_virtio: Introduce caif over virtio") Signed-off-by: Jason Wang jasowang@redhat.com Message-Id: 20220620051115.3142-3-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/caif/caif_virtio.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c index 47a6d62b7511..a701932f5cc2 100644 --- a/drivers/net/caif/caif_virtio.c +++ b/drivers/net/caif/caif_virtio.c @@ -723,13 +723,21 @@ static int cfv_probe(struct virtio_device *vdev) /* Carrier is off until netdevice is opened */ netif_carrier_off(netdev);
+ /* serialize netdev register + virtio_device_ready() with ndo_open() */ + rtnl_lock(); + /* register Netdev */ - err = register_netdev(netdev); + err = register_netdevice(netdev); if (err) { + rtnl_unlock(); dev_err(&vdev->dev, "Unable to register netdev (%d)\n", err); goto err; }
+ virtio_device_ready(vdev); + + rtnl_unlock(); + debugfs_init(cfv);
return 0;