PCI: hv: Avoid use of hv_pci_dev->pci_slot after freeing it

The slot must be removed before the pci_dev is removed, otherwise a panic
can happen due to use-after-free.

Fixes: 15becc2b56c6 ("PCI: hv: Add hv_pci_remove_slots() when we unload the driver")
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 40b6254..2b53976 100644 (file)
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -2701,8 +2701,8 @@ static int hv_pci_remove(struct hv_device *hdev)
                /* Remove the bus from PCI's point of view. */
                pci_lock_rescan_remove();
                pci_stop_root_bus(hbus->pci_bus);
-               pci_remove_root_bus(hbus->pci_bus);
                hv_pci_remove_slots(hbus);
+               pci_remove_root_bus(hbus->pci_bus);
                pci_unlock_rescan_remove();
                hbus->state = hv_pcibus_removed;
        }