3.2.78-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: "Michael S. Tsirkin" <[email protected]> commit 2989be09a8a9d62a785137586ad941f916e08f83 upstream. KASan detected a use-after-free error in virtio-pci remove code. In virtio_pci_remove(), vp_dev is still used after being freed in unregister_virtio_device() (in virtio_pci_release_dev() more precisely). To fix, keep a reference until cleanup is done. Fixes: 63bd62a08ca4 ("virtio_pci: defer kfree until release callback") Reported-by: Jerome Marchand <[email protected]> Cc: Sasha Levin <[email protected]> Signed-off-by: Michael S. Tsirkin <[email protected]> Tested-by: Jerome Marchand <[email protected]> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <[email protected]> --- drivers/virtio/virtio_pci.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -698,6 +698,7 @@ out: static void __devexit virtio_pci_remove(struct pci_dev *pci_dev) { struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); + struct device *dev = get_device(&vp_dev->vdev.dev); unregister_virtio_device(&vp_dev->vdev); @@ -706,6 +707,7 @@ static void __devexit virtio_pci_remove( pci_iounmap(pci_dev, vp_dev->ioaddr); pci_release_regions(pci_dev); pci_disable_device(pci_dev); + put_device(dev); } #ifdef CONFIG_PM
