diff options
| author | Amit Shah <amit.shah@redhat.com> | 2013-03-08 11:30:18 +1100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-20 13:10:52 -0700 |
| commit | 87dcef49efd69d89b4ca02f1739a3445b366e9df (patch) | |
| tree | fca50013e809478423b0026c466db08f05992bc7 | |
| parent | 05b96a05942994ed9748d6ef8a18361fb195c238 (diff) | |
virtio: rng: disallow multiple device registrations, fixes crashes
commit e84e7a56a3aa2963db506299e29a5f3f09377f9b upstream.
The code currently only supports one virtio-rng device at a time.
Invoking guests with multiple devices causes the guest to blow up.
Check if we've already registered and initialised the driver. Also
cleanup in case of registration errors or hot-unplug so that a new
device can be used.
Reported-by: Peter Krempa <pkrempa@redhat.com>
Reported-by: <yunzheng@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/char/hw_random/virtio-rng.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index b65c1039595..1acc4e050ae 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -92,14 +92,22 @@ static int probe_common(struct virtio_device *vdev) { int err; + if (vq) { + /* We only support one device for now */ + return -EBUSY; + } /* We expect a single virtqueue. */ vq = virtio_find_single_vq(vdev, random_recv_done, "input"); - if (IS_ERR(vq)) - return PTR_ERR(vq); + if (IS_ERR(vq)) { + err = PTR_ERR(vq); + vq = NULL; + return err; + } err = hwrng_register(&virtio_hwrng); if (err) { vdev->config->del_vqs(vdev); + vq = NULL; return err; } @@ -112,6 +120,7 @@ static void remove_common(struct virtio_device *vdev) busy = false; hwrng_unregister(&virtio_hwrng); vdev->config->del_vqs(vdev); + vq = NULL; } static int virtrng_probe(struct virtio_device *vdev) |