mv643xx_eth: potential null dereference

We assume that "pd" can be null on the previous line, and throughout the
function so we should check it here as well.  This was introduced by
9b2c2ff7a1c0 "mv643xx_eth: use sw csum for big packets"

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/net/mv643xx_eth.c b/drivers/net/mv643xx_eth.c
index 2fcdb1e1b99d..2d488abcf62d 100644
--- a/drivers/net/mv643xx_eth.c
+++ b/drivers/net/mv643xx_eth.c
@@ -2675,7 +2675,8 @@ static int mv643xx_eth_shared_probe(struct platform_device *pdev)
          * Detect hardware parameters.
          */
         msp->t_clk = (pd != NULL && pd->t_clk != 0) ? pd->t_clk : 133000000;
-        msp->tx_csum_limit = pd->tx_csum_limit ? pd->tx_csum_limit : 9 * 1024;
+        msp->tx_csum_limit = (pd != NULL && pd->tx_csum_limit) ?
+                                        pd->tx_csum_limit : 9 * 1024;
         infer_hw_params(msp);
 
         platform_set_drvdata(pdev, msp);