diff options
| author | Haiyang Zhang <haiyangz@microsoft.com> | 2015-12-10 12:19:35 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-12-14 00:02:06 -0500 |
| commit | cf8190e4c26c8ccf87d80793f8f1f7fe150cdf8c (patch) | |
| tree | ffe1bc8b5f456c63a1e1dc4a2c8e9660353451f2 | |
| parent | abe492b4f50c3ae2ebcfaa2f5c16176aebaa1c68 (diff) | |
| download | linux-cf8190e4c26c8ccf87d80793f8f1f7fe150cdf8c.tar.bz2 | |
hv_netvsc: Fix race condition on Multi-Send Data field
In commit 2a04ae8acb14 ("hv_netvsc: remove locking in netvsc_send()"), the
locking for MSD (Multi-Send Data) field was removed. This could cause a
race condition between RNDIS control messages and data packets processing,
because these two types of traffic are not synchronized.
This patch fixes this issue by sending control messages out directly
without reading MSD field.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/hyperv/netvsc.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 02bab9a7c9ff..059fc5231601 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -867,6 +867,14 @@ int netvsc_send(struct hv_device *device, packet->send_buf_index = NETVSC_INVALID_INDEX; packet->cp_partial = false; + /* Send control message directly without accessing msd (Multi-Send + * Data) field which may be changed during data packet processing. + */ + if (!skb) { + cur_send = packet; + goto send_now; + } + msdp = &net_device->msd[q_idx]; /* batch packets in send buffer if possible */ @@ -939,6 +947,7 @@ int netvsc_send(struct hv_device *device, } } +send_now: if (cur_send) ret = netvsc_send_pkt(cur_send, net_device, pb, skb); |