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[Qemu-devel] [PATCH 1/2] hw/virtio/virtio: Don't allow guests to add/rem
From: |
Peter Maydell |
Subject: |
[Qemu-devel] [PATCH 1/2] hw/virtio/virtio: Don't allow guests to add/remove queues |
Date: |
Thu, 25 Jul 2013 14:37:42 +0100 |
A queue size of 0 is used to indicate a nonexistent queue, so
don't allow the guest to flip a queue between zero-size and
non-zero-size. Don't permit setting of negative queue sizes
either.
Signed-off-by: Peter Maydell <address@hidden>
---
hw/virtio/virtio.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 09f62c6..d5b0502 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -673,10 +673,14 @@ hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n)
void virtio_queue_set_num(VirtIODevice *vdev, int n, int num)
{
- if (num <= VIRTQUEUE_MAX_SIZE) {
- vdev->vq[n].vring.num = num;
- virtqueue_init(&vdev->vq[n]);
+ if ((num == 0 && vdev->vq[n].vring.num != 0) ||
+ (num != 0 && vdev->vq[n].vring.num == 0) ||
+ (num > VIRTQUEUE_MAX_SIZE) ||
+ (num < 0)) {
+ return;
}
+ vdev->vq[n].vring.num = num;
+ virtqueue_init(&vdev->vq[n]);
}
int virtio_queue_get_num(VirtIODevice *vdev, int n)
--
1.7.9.5
[Qemu-devel] [PATCH 2/2] hw/virtio/virtio-mmio: Make QueueNumMax read 0 for unavailable queues, Peter Maydell, 2013/07/25