From 407d1634d56b841279e1478253c212ea27bb7ea0 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 14 Jan 2016 16:00:41 +0200 Subject: [PATCH] virtio_pci: fix use after free on release 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 Cc: Sasha Levin Signed-off-by: Michael S. Tsirkin Tested-by: Jerome Marchand [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings --- drivers/virtio/virtio_pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index 13f6cd8fffd2..49cc7ada4fc5 100644 --- 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(struct pci_dev *pci_dev) pci_iounmap(pci_dev, vp_dev->ioaddr); pci_release_regions(pci_dev); pci_disable_device(pci_dev); + put_device(dev); } #ifdef CONFIG_PM -- 2.39.2