Re: [PATCH 1/1] net: thunderx: avoid null pointer dereference

[David Daney]

On 05/17/2016 12:40 PM, Heinrich Schuchardt wrote:
In function bgx_lmac_handler only use a member of
lmac after checking it is not null.

Were you seeing and actual OOPs, or is this only a theoretical problem 
flagged by some sort of static code checker?

Signed-off-by: Heinrich Schuchardt <xypron.g...@gmx.de>

In any event, it seems sane to make this change, so:

Acked-by: David Daney <david.da...@cavium.com>


---
  drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c 
b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
index d20539a..3ed2198 100644
--- 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;