diff options
| author | Amit Shah <amit.shah@redhat.com> | 2011-03-14 13:15:02 +0100 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2011-04-21 15:27:00 +0200 |
| commit | 31a3ddda166cda86d2b5111e09ba4bda5239fae6 (patch) | |
| tree | 9cd6af0a5a7b59b4452db2fa84545ce782c4006b /drivers/virtio | |
| parent | virtio: Decrement avail idx on buffer detach (diff) | |
| download | linux-31a3ddda166cda86d2b5111e09ba4bda5239fae6.tar.xz linux-31a3ddda166cda86d2b5111e09ba4bda5239fae6.zip | |
virtio_pci: Prevent double-free of pci regions after device hot-unplug
In the case where a virtio-console port is in use (opened by a program)
and a virtio-console device is removed, the port is kept around but all
the virtio-related state is assumed to be gone.
When the port is finally released (close() called), we call
device_destroy() on the port's device. This results in the parent
device's structures to be freed as well. This includes the PCI regions
for the virtio-console PCI device.
Once this is done, however, virtio_pci_release_dev() kicks in, as the
last ref to the virtio device is now gone, and attempts to do
pci_iounmap(pci_dev, vp_dev->ioaddr);
pci_release_regions(pci_dev);
pci_disable_device(pci_dev);
which results in a double-free warning.
Move the code that releases regions, etc., to the virtio_pci_remove()
function, and all that's now left in release_dev is the final freeing of
the vp_dev.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/virtio')
| -rw-r--r-- | drivers/virtio/virtio_pci.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c index 4fb5b2bf2348..4bcc8b82640b 100644 --- a/drivers/virtio/virtio_pci.c +++ b/drivers/virtio/virtio_pci.c @@ -590,15 +590,10 @@ 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_device *dev = container_of(_d, struct virtio_device, + dev); struct virtio_pci_device *vp_dev = to_vp_device(dev); - struct pci_dev *pci_dev = vp_dev->pci_dev; - vp_del_vqs(dev); - pci_set_drvdata(pci_dev, NULL); - pci_iounmap(pci_dev, vp_dev->ioaddr); - pci_release_regions(pci_dev); - pci_disable_device(pci_dev); kfree(vp_dev); } @@ -681,6 +676,12 @@ static void __devexit virtio_pci_remove(struct pci_dev *pci_dev) struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev); unregister_virtio_device(&vp_dev->vdev); + + vp_del_vqs(&vp_dev->vdev); + pci_set_drvdata(pci_dev, NULL); + pci_iounmap(pci_dev, vp_dev->ioaddr); + pci_release_regions(pci_dev); + pci_disable_device(pci_dev); } #ifdef CONFIG_PM |