[PATCH] vfio: Fix NULL pointer dereference in vfio_pci_bus_notifier

[Kunwu Chan]

kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure. Ensure the allocation was successful
by checking the pointer validity.

Signed-off-by: Kunwu Chan <chentao@xxxxxxxxxx>
---
 drivers/vfio/pci/vfio_pci_core.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index 1cbc990d42e0..74e5b89a3a0c 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -2047,6 +2047,8 @@ static int vfio_pci_bus_notifier(struct notifier_block *nb,
 			 pci_name(pdev));
 		pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
 						  vdev->vdev.ops->name);
+		if (!pdev->driver_override)
+			return -ENOMEM;
 	} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
 		   pdev->is_virtfn && physfn == vdev->pdev) {
 		struct pci_driver *drv = pci_dev_driver(pdev);
-- 
2.39.2