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/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index e620374..0054b69 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -183,10 +183,12 @@
/* Interface */
struct rndis_message;
struct netvsc_device;
+struct net_device_context;
+
struct netvsc_device *netvsc_device_add(struct hv_device *device,
const struct netvsc_device_info *info);
void netvsc_device_remove(struct hv_device *device);
-int netvsc_send(struct hv_device *device,
+int netvsc_send(struct net_device_context *ndc,
struct hv_netvsc_packet *packet,
struct rndis_message *rndis_msg,
struct hv_page_buffer **page_buffer,
@@ -790,12 +792,6 @@
return ((struct net_device_context *)netdev_priv(ndev))->nvdev;
}
-static inline struct netvsc_device *
-hv_device_to_netvsc_device(struct hv_device *device)
-{
- return net_device_to_netvsc_device(hv_get_drvdata(device));
-}
-
/* NdisInitialize message */
struct rndis_initialize_request {
u32 req_id;
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/* If device is rescinded, return error and packet will get dropped.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
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 0ca8c74..1238600 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -505,8 +505,8 @@
/* timestamp packet in software */
skb_tx_timestamp(skb);
- ret = netvsc_send(net_device_ctx->device_ctx, packet,
- rndis_msg, &pb, skb);
+
+ ret = netvsc_send(net_device_ctx, packet, rndis_msg, &pb, skb);
if (likely(ret == 0))
return NETDEV_TX_OK;
diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index cacf1e5..9ab67c8 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -243,7 +243,7 @@
pb[0].len;
}
- ret = netvsc_send(net_device_ctx->device_ctx, packet, NULL, &pb, NULL);
+ ret = netvsc_send(net_device_ctx, packet, NULL, &pb, NULL);
return ret;
}