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

[ Upstream commit 533ca1feed98b0bf024779a14760694c7cb4d431 ]

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
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c
index 5a9d945122327e9b68a3a6f53e3112a512c00400..70825689e5a0844250d0476ce083b7bb650448b6 100644 (file)
--- a/drivers/pci/host/pci-hyperv.c
+++ b/drivers/pci/host/pci-hyperv.c
@@ -2740,8 +2740,8 @@ 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;
        }