qlcnic: Avoid potential NULL pointer dereference

BugLink: https://bugs.launchpad.net/bugs/1838459
[ Upstream commit 5bf7295fe34a5251b1d241b9736af4697b590670 ]

netdev_alloc_skb can fail and return a NULL pointer which is
dereferenced without a check. The patch avoids such a scenario.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c
index 7f7deeaf1cf07913454a13b4f7801c7b3b07545f..da042bc520d46388d5cb915802905deaac4c15ad 100644 (file)
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ethtool.c
@@ -1047,6 +1047,8 @@ int qlcnic_do_lb_test(struct qlcnic_adapter *adapter, u8 mode)
 
        for (i = 0; i < QLCNIC_NUM_ILB_PKT; i++) {
                skb = netdev_alloc_skb(adapter->netdev, QLCNIC_ILB_PKT_SIZE);
+               if (!skb)
+                       break;
                qlcnic_create_loopback_buff(skb->data, adapter->mac_addr);
                skb_put(skb, QLCNIC_ILB_PKT_SIZE);
                adapter->ahw->diag_cnt = 0;