[PATCH AUTOSEL 5.4 108/187] hv_netvsc: Fix tx_table init in rndis_set_subchannel()

From: Sasha Levin
Date: Fri Dec 27 2019 - 12:43:09 EST


From: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>

[ Upstream commit c39ea5cba5a2e97fc01b78c85208bf31383b399c ]

Host can provide send indirection table messages anytime after RSS is
enabled by calling rndis_filter_set_rss_param(). So the host provided
table values may be overwritten by the initialization in
rndis_set_subchannel().

To prevent this problem, move the tx_table initialization before calling
rndis_filter_set_rss_param().

Fixes: a6fb6aa3cfa9 ("hv_netvsc: Set tx_table to equal weight after subchannels open")
Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <jakub.kicinski@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/hyperv/rndis_filter.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c
index abaf8156d19d..e3d3c9097ff1 100644
--- a/drivers/net/hyperv/rndis_filter.c
+++ b/drivers/net/hyperv/rndis_filter.c
@@ -1165,6 +1165,9 @@ int rndis_set_subchannel(struct net_device *ndev,
wait_event(nvdev->subchan_open,
atomic_read(&nvdev->open_chn) == nvdev->num_chn);

+ for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
+ ndev_ctx->tx_table[i] = i % nvdev->num_chn;
+
/* ignore failures from setting rss parameters, still have channels */
if (dev_info)
rndis_filter_set_rss_param(rdev, dev_info->rss_key);
@@ -1174,9 +1177,6 @@ int rndis_set_subchannel(struct net_device *ndev,
netif_set_real_num_tx_queues(ndev, nvdev->num_chn);
netif_set_real_num_rx_queues(ndev, nvdev->num_chn);

- for (i = 0; i < VRSS_SEND_TAB_SIZE; i++)
- ndev_ctx->tx_table[i] = i % nvdev->num_chn;
-
return 0;
}

--
2.20.1