net/hyperv: Adding cancellation to ensure rndis filter is closed
authorWenqi Ma <wenqi_ma@trendmicro.com.cn>
Thu, 19 Apr 2012 00:39:37 +0000 (00:39 +0000)
committerDavid S. Miller <davem@davemloft.net>
Sat, 21 Apr 2012 19:38:10 +0000 (15:38 -0400)
Although the network interface is down, the RX packets number which
could be observed by ifconfig may keep on increasing.

This is because the WORK scheduled in netvsc_set_multicast_list()
may be executed after netvsc_close(). That means the rndis filter
may be re-enabled by do_set_multicast() even if it was closed by
netvsc_close().

By canceling possible WORK before close the rndis filter, the issue
could be never happened.

Signed-off-by: Wenqi Ma <wenqi_ma@trendmicro.com.cn>
Reviewed-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/hyperv/netvsc_drv.c

index dd294783b5c5b77c3d48ecd14067921d9e90d4bb..2d59138db7f3fd688840d6bf5ce1f449838271be 100644 (file)
@@ -44,6 +44,7 @@ struct net_device_context {
        /* point back to our device context */
        struct hv_device *device_ctx;
        struct delayed_work dwork;
+       struct work_struct work;
 };
 
 
@@ -51,30 +52,22 @@ static int ring_size = 128;
 module_param(ring_size, int, S_IRUGO);
 MODULE_PARM_DESC(ring_size, "Ring buffer size (# of pages)");
 
-struct set_multicast_work {
-       struct work_struct work;
-       struct net_device *net;
-};
-
 static void do_set_multicast(struct work_struct *w)
 {
-       struct set_multicast_work *swk =
-               container_of(w, struct set_multicast_work, work);
-       struct net_device *net = swk->net;
-
-       struct net_device_context *ndevctx = netdev_priv(net);
+       struct net_device_context *ndevctx =
+               container_of(w, struct net_device_context, work);
        struct netvsc_device *nvdev;
        struct rndis_device *rdev;
 
        nvdev = hv_get_drvdata(ndevctx->device_ctx);
-       if (nvdev == NULL)
-               goto out;
+       if (nvdev == NULL || nvdev->ndev == NULL)
+               return;
 
        rdev = nvdev->extension;
        if (rdev == NULL)
-               goto out;
+               return;
 
-       if (net->flags & IFF_PROMISC)
+       if (nvdev->ndev->flags & IFF_PROMISC)
                rndis_filter_set_packet_filter(rdev,
                        NDIS_PACKET_TYPE_PROMISCUOUS);
        else
@@ -82,21 +75,13 @@ static void do_set_multicast(struct work_struct *w)
                        NDIS_PACKET_TYPE_BROADCAST |
                        NDIS_PACKET_TYPE_ALL_MULTICAST |
                        NDIS_PACKET_TYPE_DIRECTED);
-
-out:
-       kfree(w);
 }
 
 static void netvsc_set_multicast_list(struct net_device *net)
 {
-       struct set_multicast_work *swk =
-               kmalloc(sizeof(struct set_multicast_work), GFP_ATOMIC);
-       if (swk == NULL)
-               return;
+       struct net_device_context *net_device_ctx = netdev_priv(net);
 
-       swk->net = net;
-       INIT_WORK(&swk->work, do_set_multicast);
-       schedule_work(&swk->work);
+       schedule_work(&net_device_ctx->work);
 }
 
 static int netvsc_open(struct net_device *net)
@@ -125,6 +110,8 @@ static int netvsc_close(struct net_device *net)
 
        netif_tx_disable(net);
 
+       /* Make sure netvsc_set_multicast_list doesn't re-enable filter! */
+       cancel_work_sync(&net_device_ctx->work);
        ret = rndis_filter_close(device_obj);
        if (ret != 0)
                netdev_err(net, "unable to close device (ret %d).\n", ret);
@@ -335,6 +322,7 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 
        nvdev->start_remove = true;
        cancel_delayed_work_sync(&ndevctx->dwork);
+       cancel_work_sync(&ndevctx->work);
        netif_tx_disable(ndev);
        rndis_filter_device_remove(hdev);
 
@@ -403,6 +391,7 @@ static int netvsc_probe(struct hv_device *dev,
        net_device_ctx->device_ctx = dev;
        hv_set_drvdata(dev, net);
        INIT_DELAYED_WORK(&net_device_ctx->dwork, netvsc_send_garp);
+       INIT_WORK(&net_device_ctx->work, do_set_multicast);
 
        net->netdev_ops = &device_ops;
 
@@ -456,6 +445,7 @@ static int netvsc_remove(struct hv_device *dev)
 
        ndev_ctx = netdev_priv(net);
        cancel_delayed_work_sync(&ndev_ctx->dwork);
+       cancel_work_sync(&ndev_ctx->work);
 
        /* Stop outbound asap */
        netif_tx_disable(net);