netxen: check for root bus in netxen_mask_aer_correctable

[ Upstream commit e4d1aa40e363ed3e0486aeeeb0d173f7f822737e ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/netxen/netxen_nic_main.c b/drivers/net/netxen/netxen_nic_main.c
index c0788a31ff0f4a8c0ee8b637ba335e69b7cd3056..78d5b674757b91e08f51f5efacc8d1821656cbbe 100644 (file)
--- a/drivers/net/netxen/netxen_nic_main.c
+++ b/drivers/net/netxen/netxen_nic_main.c
@@ -1288,6 +1288,10 @@ 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;