hyperv: Move wait completion msg code into rndis_filter_halt_device()

We need to wait for send_completion msg before put_rndis_request() at
the end of rndis_filter_halt_device(). Otherwise, netvsc_send_completion()
may reference freed memory which is overwritten, and cause panic.

Reported-by: Long Li <longli@microsoft.com>
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 6cee291..4a1a5f5 100644 (file)
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -383,13 +383,6 @@ int netvsc_device_remove(struct hv_device *device)
        unsigned long flags;
 
        net_device = hv_get_drvdata(device);
-       spin_lock_irqsave(&device->channel->inbound_lock, flags);
-       net_device->destroy = true;
-       spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
-
-       /* Wait for all send completions */
-       wait_event(net_device->wait_drain,
-                  atomic_read(&net_device->num_outstanding_sends) == 0);
 
        netvsc_disconnect_vsp(net_device);
 

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index e5d6146..1e88a10 100644 (file)
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -718,6 +718,9 @@ static void rndis_filter_halt_device(struct rndis_device *dev)
 {
        struct rndis_request *request;
        struct rndis_halt_request *halt;
+       struct netvsc_device *nvdev = dev->net_dev;
+       struct hv_device *hdev = nvdev->dev;
+       ulong flags;
 
        /* Attempt to do a rndis device halt */
        request = get_rndis_request(dev, RNDIS_MSG_HALT,
@@ -735,6 +738,14 @@ static void rndis_filter_halt_device(struct rndis_device *dev)
        dev->state = RNDIS_DEV_UNINITIALIZED;
 
 cleanup:
+       spin_lock_irqsave(&hdev->channel->inbound_lock, flags);
+       nvdev->destroy = true;
+       spin_unlock_irqrestore(&hdev->channel->inbound_lock, flags);
+
+       /* Wait for all send completions */
+       wait_event(nvdev->wait_drain,
+               atomic_read(&nvdev->num_outstanding_sends) == 0);
+
        if (request)
                put_rndis_request(dev, request);
        return;