| Message ID | 20170316192132.9095-1-sthemmin@microsoft.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Stephen Hemminger <stephen@networkplumber.org> Date: Thu, 16 Mar 2017 12:21:32 -0700 > When device is being setup on boot, there is a small race where > network device callback is registered, but the netvsc_device pointer > is not set yet. This can cause a NULL ptr dereference if packet > arrives during this window. > > Fixes: 46b4f7f5d1f7 ("netvsc: eliminate per-device outstanding send counter") > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> > --- > Applies to 4.11 only, not in earlier versions. > net-next needs different patch Applied, thanks Stephen.
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 4c1d8cca247b..8dd0b8770328 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -1231,8 +1231,11 @@ void netvsc_channel_cb(void *context) return; net_device = net_device_to_netvsc_device(ndev); - if (unlikely(net_device->destroy) && - netvsc_channel_idle(net_device, q_idx)) + if (unlikely(!net_device)) + return; + + if (unlikely(net_device->destroy && + netvsc_channel_idle(net_device, q_idx))) return; /* commit_rd_index() -> hv_signal_on_read() needs this. */
When device is being setup on boot, there is a small race where network device callback is registered, but the netvsc_device pointer is not set yet. This can cause a NULL ptr dereference if packet arrives during this window. Fixes: 46b4f7f5d1f7 ("netvsc: eliminate per-device outstanding send counter") Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> --- Applies to 4.11 only, not in earlier versions. net-next needs different patch drivers/net/hyperv/netvsc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)