[patch net] rocker: fix possible null pointer dereference in rocker_router_fib_event_work

[Jiri Pirko]

From: Jiri Pirko <j...@mellanox.com>

Currently, rocker user may experience following null pointer
derefence bug:

[    3.062141] BUG: unable to handle kernel NULL pointer dereference at 
00000000000000d0
[    3.065163] IP: rocker_router_fib_event_work+0x36/0x110 [rocker]

The problem is uninitialized rocker->wops pointer that is initialized
only with the first initialized port. So move the port initialization
before registering the fib events.

Fixes: 936bd486564a ("rocker: use FIB notifications instead of switchdev calls")
Signed-off-by: Jiri Pirko <j...@mellanox.com>
---
 drivers/net/ethernet/rocker/rocker_main.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/rocker/rocker_main.c 
b/drivers/net/ethernet/rocker/rocker_main.c
index fc8f8bdf6579..056cb6093630 100644
--- a/drivers/net/ethernet/rocker/rocker_main.c
+++ b/drivers/net/ethernet/rocker/rocker_main.c
@@ -2902,6 +2902,12 @@ static int rocker_probe(struct pci_dev *pdev, const 
struct pci_device_id *id)
                goto err_alloc_ordered_workqueue;
        }
 
+       err = rocker_probe_ports(rocker);
+       if (err) {
+               dev_err(&pdev->dev, "failed to probe ports\n");
+               goto err_probe_ports;
+       }
+
        /* Only FIBs pointing to our own netdevs are programmed into
         * the device, so no need to pass a callback.
         */
@@ -2918,22 +2924,16 @@ static int rocker_probe(struct pci_dev *pdev, const 
struct pci_device_id *id)
 
        rocker->hw.id = rocker_read64(rocker, SWITCH_ID);
 
-       err = rocker_probe_ports(rocker);
-       if (err) {
-               dev_err(&pdev->dev, "failed to probe ports\n");
-               goto err_probe_ports;
-       }
-
        dev_info(&pdev->dev, "Rocker switch with id %*phN\n",
                 (int)sizeof(rocker->hw.id), &rocker->hw.id);
 
        return 0;
 
-err_probe_ports:
-       unregister_switchdev_notifier(&rocker_switchdev_notifier);
 err_register_switchdev_notifier:
        unregister_fib_notifier(&rocker->fib_nb);
 err_register_fib_notifier:
+       rocker_remove_ports(rocker);
+err_probe_ports:
        destroy_workqueue(rocker->rocker_owq);
 err_alloc_ordered_workqueue:
        free_irq(rocker_msix_vector(rocker, ROCKER_MSIX_VEC_EVENT), rocker);
@@ -2961,9 +2961,9 @@ static void rocker_remove(struct pci_dev *pdev)
 {
        struct rocker *rocker = pci_get_drvdata(pdev);
 
-       rocker_remove_ports(rocker);
        unregister_switchdev_notifier(&rocker_switchdev_notifier);
        unregister_fib_notifier(&rocker->fib_nb);
+       rocker_remove_ports(rocker);
        rocker_write32(rocker, CONTROL, ROCKER_CONTROL_RESET);
        destroy_workqueue(rocker->rocker_owq);
        free_irq(rocker_msix_vector(rocker, ROCKER_MSIX_VEC_EVENT), rocker);
-- 
2.14.3