[PATCH 4.19 112/125] hv_netvsc: Fix error handling in netvsc_attach()

From: Greg Kroah-Hartman
Date: Mon Nov 11 2019 - 13:46:25 EST


From: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>

[ Upstream commit 719b85c336ed35565d0f3982269d6f684087bb00 ]

If rndis_filter_open() fails, we need to remove the rndis device created
in earlier steps, before returning an error code. Otherwise, the retry of
netvsc_attach() from its callers will fail and hang.

Fixes: 7b2ee50c0cd5 ("hv_netvsc: common detach logic")
Signed-off-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/hyperv/netvsc_drv.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 6f6c0dbd91fc8..b7a71c203aa37 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -993,7 +993,7 @@ static int netvsc_attach(struct net_device *ndev,
if (netif_running(ndev)) {
ret = rndis_filter_open(nvdev);
if (ret)
- return ret;
+ goto err;

rdev = nvdev->extension;
if (!rdev->link_state)
@@ -1001,6 +1001,13 @@ static int netvsc_attach(struct net_device *ndev,
}

return 0;
+
+err:
+ netif_device_detach(ndev);
+
+ rndis_filter_device_remove(hdev, nvdev);
+
+ return ret;
}

static int netvsc_set_channels(struct net_device *net,
--
2.20.1