lkml.org 
[lkml]   [2013]   [Mar]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 022/150] virtio: rng: disallow multiple device registrations, fixes crashes
Date
3.5.7.9 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Amit Shah <amit.shah@redhat.com>

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: Luis Henriques <luis.henriques@canonical.com>
---
drivers/char/hw_random/virtio-rng.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c
index 723725b..171380b 100644
--- a/drivers/char/hw_random/virtio-rng.c
+++ b/drivers/char/hw_random/virtio-rng.c
@@ -89,14 +89,22 @@ static int virtrng_probe(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;
}

@@ -108,6 +116,7 @@ static void __devexit virtrng_remove(struct virtio_device *vdev)
vdev->config->reset(vdev);
hwrng_unregister(&virtio_hwrng);
vdev->config->del_vqs(vdev);
+ vq = NULL;
}

static struct virtio_device_id id_table[] = {
--
1.8.1.2


\
 
 \ /
  Last update: 2013-03-28 07:41    [W:0.363 / U:0.724 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site