netxen: check for root bus in netxen_mask_aer_correctable

Add a check if pdev->bus->self == NULL (root bus). When attaching
a netxen NIC to a VM it can be on the root bus and the guest would
crash in netxen_mask_aer_correctable() because of a NULL pointer
dereference if CONFIG_PCIEAER is present.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c b/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
index 342b3a79bd0f..a77c558d8f40 100644
--- a/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
+++ b/drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c
@@ -1378,6 +1378,10 @@ static void netxen_mask_aer_correctable(struct netxen_adapter *adapter)
         struct pci_dev *root = pdev->bus->self;
         u32 aer_pos;
 
+        /* root bus? */
+        if (!root)
+                return;
+
         if (adapter->ahw.board_type != NETXEN_BRDTYPE_P3_4_GB_MM &&
                 adapter->ahw.board_type != NETXEN_BRDTYPE_P3_10G_TP)
                 return;