ice: add NULL check in eswitch lag check

[ Upstream commit 3ce58b01ada408b372f15b7c992ed0519840e3cf ]

The function ice_lag_is_switchdev_running() is being called from outside of
the LAG event handler code.  This results in the lag->upper_netdev being
NULL sometimes.  To avoid a NULL-pointer dereference, there needs to be a
check before it is dereferenced.

Fixes: 776fe19953b0 ("ice: block default rule setting on LAG interface")
Signed-off-by: Dave Ertman <david.m.ertman@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Tested-by: Sujai Buvaneswaran <sujai.buvaneswaran@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/intel/ice/ice_lag.c b/drivers/net/ethernet/intel/ice/ice_lag.c
index 4db0b770420e651df53fa1b5da67c4d3f1aaedf9..8ed9918ea4e894786fe93cf3eb6ec48e67aa87a4 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_lag.c
+++ b/drivers/net/ethernet/intel/ice/ice_lag.c
@@ -2129,7 +2129,8 @@ bool ice_lag_is_switchdev_running(struct ice_pf *pf)
        struct ice_lag *lag = pf->lag;
        struct net_device *tmp_nd;
 
-       if (!ice_is_feature_supported(pf, ICE_F_SRIOV_LAG) || !lag)
+       if (!ice_is_feature_supported(pf, ICE_F_SRIOV_LAG) ||
+           !lag || !lag->upper_netdev)
                return false;
 
        rcu_read_lock();