netvsc: need rcu_derefence when accessing internal device info
The netvsc_device structure should be accessed by rcu_dereference
in the send path. Change arguments to netvsc_send() to make
this easier to do correctly.
Remove no longer needed hv_device_to_netvsc_device.
Signed-off-by: Stephen Hemminger <sthemmin@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 4a25505..3c6f3ae 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -822,13 +822,15 @@
msdp->count = 0;
}
-int netvsc_send(struct hv_device *device,
+/* RCU already held by caller */
+int netvsc_send(struct net_device_context *ndev_ctx,
struct hv_netvsc_packet *packet,
struct rndis_message *rndis_msg,
struct hv_page_buffer **pb,
struct sk_buff *skb)
{
- struct netvsc_device *net_device = hv_device_to_netvsc_device(device);
+ struct netvsc_device *net_device = rcu_dereference(ndev_ctx->nvdev);
+ struct hv_device *device = ndev_ctx->device_ctx;
int ret = 0;
struct netvsc_channel *nvchan;
u32 pktlen = packet->total_data_buflen, msd_len = 0;
@@ -840,7 +842,7 @@
bool xmit_more = (skb != NULL) ? skb->xmit_more : false;
/* If device is rescinded, return error and packet will get dropped. */
- if (unlikely(net_device->destroy))
+ if (unlikely(!net_device || net_device->destroy))
return -ENODEV;
/* We may race with netvsc_connect_vsp()/netvsc_init_buf() and get