| Message ID | 1530270944-11351-3-git-send-email-suzuki.poulose@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jun 29, 2018 at 12:15:22PM +0100, Suzuki K Poulose wrote: > Legacy PCI over virtio uses a 32bit PFN for the queue. If the > queue pfn is too large to fit in 32bits, which we could hit on > arm64 systems with 52bit physical addresses (even with 64K page > size), we simply miss out a proper link to the other side of > the queue. > > Add a check to validate the PFN, rather than silently breaking > the devices. > > Cc: "Michael S. Tsirkin" <mst@redhat.com> > Cc: Jason Wang <jasowang@redhat.com> > Cc: Marc Zyngier <marc.zyngier@arm.com> > Cc: Christoffer Dall <cdall@kernel.org> > Cc: Peter Maydel <peter.maydell@linaro.org> > Cc: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > --- > Changes since v2: > - Change errno to -E2BIG > --- > drivers/virtio/virtio_pci_legacy.c | 12 ++++++++++-- > 1 file changed, 10 insertions(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c > index 2780886..c0d6987a 100644 > --- a/drivers/virtio/virtio_pci_legacy.c > +++ b/drivers/virtio/virtio_pci_legacy.c > @@ -122,6 +122,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > struct virtqueue *vq; > u16 num; > int err; > + u64 q_pfn; > > /* Select the queue we're interested in */ > iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); > @@ -141,9 +142,15 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > if (!vq) > return ERR_PTR(-ENOMEM); > > + q_pfn = virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT; > + if (q_pfn >> 32) { > + dev_err(&vp_dev->pci_dev->dev, "virtio-pci queue PFN too large\n"); > + err = -E2BIG; Same comment here. Let's make it clear it's host not guest problem. > + goto out_del_vq; > + } > + > /* activate the queue */ > - iowrite32(virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, > - vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); > + iowrite32(q_pfn, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); > > vq->priv = (void __force *)vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY; > > @@ -160,6 +167,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, > > out_deactivate: > iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); > +out_del_vq: > vring_del_virtqueue(vq); > return ERR_PTR(err); > } > -- > 2.7.4
diff --git a/drivers/virtio/virtio_pci_legacy.c b/drivers/virtio/virtio_pci_legacy.c index 2780886..c0d6987a 100644 --- a/drivers/virtio/virtio_pci_legacy.c +++ b/drivers/virtio/virtio_pci_legacy.c @@ -122,6 +122,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, struct virtqueue *vq; u16 num; int err; + u64 q_pfn; /* Select the queue we're interested in */ iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL); @@ -141,9 +142,15 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, if (!vq) return ERR_PTR(-ENOMEM); + q_pfn = virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT; + if (q_pfn >> 32) { + dev_err(&vp_dev->pci_dev->dev, "virtio-pci queue PFN too large\n"); + err = -E2BIG; + goto out_del_vq; + } + /* activate the queue */ - iowrite32(virtqueue_get_desc_addr(vq) >> VIRTIO_PCI_QUEUE_ADDR_SHIFT, - vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); + iowrite32(q_pfn, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); vq->priv = (void __force *)vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY; @@ -160,6 +167,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, out_deactivate: iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN); +out_del_vq: vring_del_virtqueue(vq); return ERR_PTR(err); }
Legacy PCI over virtio uses a 32bit PFN for the queue. If the queue pfn is too large to fit in 32bits, which we could hit on arm64 systems with 52bit physical addresses (even with 64K page size), we simply miss out a proper link to the other side of the queue. Add a check to validate the PFN, rather than silently breaking the devices. Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoffer Dall <cdall@kernel.org> Cc: Peter Maydel <peter.maydell@linaro.org> Cc: Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> --- Changes since v2: - Change errno to -E2BIG --- drivers/virtio/virtio_pci_legacy.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)