projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| 858d99c4 GKH |
1 | From e84e7a56a3aa2963db506299e29a5f3f09377f9b Mon Sep 17 00:00:00 2001 |
| 2 | From: Amit Shah <amit.shah@redhat.com> | |
| 3 | Date: Fri, 8 Mar 2013 11:30:18 +1100 | |
| 4 | Subject: virtio: rng: disallow multiple device registrations, fixes crashes | |
| 5 | ||
| 6 | From: Amit Shah <amit.shah@redhat.com> | |
| 7 | ||
| 8 | commit e84e7a56a3aa2963db506299e29a5f3f09377f9b upstream. | |
| 9 | ||
| 10 | The code currently only supports one virtio-rng device at a time. | |
| 11 | Invoking guests with multiple devices causes the guest to blow up. | |
| 12 | ||
| 13 | Check if we've already registered and initialised the driver. Also | |
| 14 | cleanup in case of registration errors or hot-unplug so that a new | |
| 15 | device can be used. | |
| 16 | ||
| 17 | Reported-by: Peter Krempa <pkrempa@redhat.com> | |
| 18 | Reported-by: <yunzheng@redhat.com> | |
| 19 | Signed-off-by: Amit Shah <amit.shah@redhat.com> | |
| 20 | Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> | |
| 21 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 22 | ||
| 23 | --- | |
| 24 | drivers/char/hw_random/virtio-rng.c | 13 +++++++++++-- | |
| 25 | 1 file changed, 11 insertions(+), 2 deletions(-) | |
| 26 | ||
| 27 | --- a/drivers/char/hw_random/virtio-rng.c | |
| 28 | +++ b/drivers/char/hw_random/virtio-rng.c | |
| 29 | @@ -92,14 +92,22 @@ static int probe_common(struct virtio_de | |
| 30 | { | |
| 31 | int err; | |
| 32 | ||
| 33 | + if (vq) { | |
| 34 | + /* We only support one device for now */ | |
| 35 | + return -EBUSY; | |
| 36 | + } | |
| 37 | /* We expect a single virtqueue. */ | |
| 38 | vq = virtio_find_single_vq(vdev, random_recv_done, "input"); | |
| 39 | - if (IS_ERR(vq)) | |
| 40 | - return PTR_ERR(vq); | |
| 41 | + if (IS_ERR(vq)) { | |
| 42 | + err = PTR_ERR(vq); | |
| 43 | + vq = NULL; | |
| 44 | + return err; | |
| 45 | + } | |
| 46 | ||
| 47 | err = hwrng_register(&virtio_hwrng); | |
| 48 | if (err) { | |
| 49 | vdev->config->del_vqs(vdev); | |
| 50 | + vq = NULL; | |
| 51 | return err; | |
| 52 | } | |
| 53 | ||
| 54 | @@ -112,6 +120,7 @@ static void remove_common(struct virtio_ | |
| 55 | busy = false; | |
| 56 | hwrng_unregister(&virtio_hwrng); | |
| 57 | vdev->config->del_vqs(vdev); | |
| 58 | + vq = NULL; | |
| 59 | } | |
| 60 | ||
| 61 | static int virtrng_probe(struct virtio_device *vdev) |