[PATCH 5.15 017/110] vdpa: fix use-after-free on vp_vdpa_remove

Greg Kroah-Hartman
2022-03-14T12:13:38Z

From: Zhang Min <zhang.min9@zte.com.cn>

[ Upstream commit eb057b44dbe35ae14527830236a92f51de8f9184 ]

When vp_vdpa driver is unbind, vp_vdpa is freed in vdpa_unregister_device
and then vp_vdpa->mdev.pci_dev is dereferenced in vp_modern_remove,
triggering use-after-free.

Call Trace of unbinding driver free vp_vdpa :
do_syscall_64
vfs_write
kernfs_fop_write_iter
device_release_driver_internal
pci_device_remove
vp_vdpa_remove
vdpa_unregister_device
kobject_release
device_release
kfree

Call Trace of dereference vp_vdpa->mdev.pci_dev:
vp_modern_remove
pci_release_selected_regions
pci_release_region
pci_resource_len
pci_resource_end
(dev)->resource[(bar)].end

Signed-off-by: Zhang Min <zhang.min9@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Link: https://lore.kernel.org/r/20220301091059.46869-1-wang.yi59@zte.com.cn
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: 64b9f64f80a6 ("vdpa: introduce virtio pci driver")
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/vdpa/virtio_pci/vp_vdpa.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index 5bcd00246d2e..dead832b4571 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -513,8 +513,8 @@ static void vp_vdpa_remove(struct pci_dev *pdev)
{
struct vp_vdpa *vp_vdpa = pci_get_drvdata(pdev);

- vdpa_unregister_device(&vp_vdpa->vdpa);
vp_modern_remove(&vp_vdpa->mdev);
+ vdpa_unregister_device(&vp_vdpa->vdpa);
}

static struct pci_driver vp_vdpa_driver = {
--
2.34.1