net: thunderx: avoid null pointer dereference

In function bgx_lmac_handler only use a member of
lmac after checking it is not null.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
index d20539a6d162bd5f0dbbd9c79d89e6784e37b969..3ed21988626b5ffaceb4e72e0276c63cee1c4347 100644 (file)
--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
@@ -274,12 +274,14 @@ static void bgx_sgmii_change_link_state(struct lmac *lmac)
 static void bgx_lmac_handler(struct net_device *netdev)
 {
        struct lmac *lmac = container_of(netdev, struct lmac, netdev);
-       struct phy_device *phydev = lmac->phydev;
+       struct phy_device *phydev;
        int link_changed = 0;
 
        if (!lmac)
                return;
 
+       phydev = lmac->phydev;
+
        if (!phydev->link && lmac->last_link)
                link_changed = -1;