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| author | Michael S. Tsirkin <mst@redhat.com> | 2011-11-07 18:37:05 +0200 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2011-11-14 11:16:26 +1030 |
| commit | 72103bd1285211440621f2c46f4fce377584de54 (patch) | |
| tree | 5bde795c7150c0802fb5a9c9e8603580e6febeae | |
| parent | 1ea6b8f48918282bdca0b32a34095504ee65bab5 (diff) | |
| download | op-kernel-dev-72103bd1285211440621f2c46f4fce377584de54.zip op-kernel-dev-72103bd1285211440621f2c46f4fce377584de54.tar.gz | |
virtio-pci: fix use after free
Commit 31a3ddda166cda86d2b5111e09ba4bda5239fae6 introduced
a use after free in virtio-pci. The main issue is
that the release method signals removal of the virtio device,
while remove signals removal of the pci device.
For example, on driver removal or hot-unplug,
virtio_pci_release_dev is called before virtio_pci_remove.
We then might get a crash as virtio_pci_remove tries to use the
device freed by virtio_pci_release_dev.
We allocate/free all resources together with the
pci device, so we can leave the release method empty.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
| -rw-r--r-- | drivers/virtio/virtio_pci.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index 79a31e5..3d1bf41 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -594,11 +594,11 @@ static struct virtio_config_ops virtio_pci_config_ops = { static void virtio_pci_release_dev(struct device *_d) { - struct virtio_device *dev = container_of(_d, struct virtio_device, - dev); - struct virtio_pci_device *vp_dev = to_vp_device(dev); - - kfree(vp_dev); + /* + * No need for a release method as we allocate/free + * all devices together with the pci devices. + * Provide an empty one to avoid getting a warning from core. + */ } /* the PCI probing function */ @@ -686,6 +686,7 @@ 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); + kfree(vp_dev); } #ifdef CONFIG_PM |
