[PATCH 4.19 110/361] failover: Add missing check to validate slave_dev in net_failover_slave_unregister

From: Greg Kroah-Hartman
Date: Sun Nov 11 2018 - 19:10:39 EST


4.19-stable review patch. If anyone has any objections, please let me know.

------------------

From: YueHaibing <yuehaibing@xxxxxxxxxx>

[ Upstream commit 9e7e6cabf371cc008cb2244a04c012b516753693 ]

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/net_failover.c: In function 'net_failover_slave_unregister':
drivers/net/net_failover.c:598:35: warning:
variable 'primary_dev' set but not used [-Wunused-but-set-variable]

There should check the validity of 'slave_dev'.

Fixes: cfc80d9a1163 ("net: Introduce net_failover driver")

Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Acked-by: Sridhar Samudrala <sridhar.samudrala@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/net_failover.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/net/net_failover.c
+++ b/drivers/net/net_failover.c
@@ -603,6 +603,9 @@ static int net_failover_slave_unregister
primary_dev = rtnl_dereference(nfo_info->primary_dev);
standby_dev = rtnl_dereference(nfo_info->standby_dev);

+ if (WARN_ON_ONCE(slave_dev != primary_dev && slave_dev != standby_dev))
+ return -ENODEV;
+
vlan_vids_del_by_dev(slave_dev, failover_dev);
dev_uc_unsync(slave_dev, failover_dev);
dev_mc_unsync(slave_dev, failover_dev);