diff options
| author | Amit Shah <amit.shah@redhat.com> | 2013-03-08 11:30:18 +1100 |
|---|---|---|
| committer | Rusty Russell <rusty@rustcorp.com.au> | 2013-03-08 11:30:43 +1100 |
| commit | e84e7a56a3aa2963db506299e29a5f3f09377f9b (patch) | |
| tree | 3c368fc922977af1760932c55fcfb69e20126cfa /drivers/char | |
| parent | f7f154f1246ccc5a0a7e9ce50932627d60a0c878 (diff) | |
| download | linux-e84e7a56a3aa2963db506299e29a5f3f09377f9b.tar.gz | |
virtio: rng: disallow multiple device registrations, fixes crashes
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> Cc: stable@kernel.org
Diffstat (limited to 'drivers/char')
| -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 10fd71ccf587..6bf4d47324eb 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) |