On Thu, 21 Sep 2023 10:02:53 -0400, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote: > On Mon, Aug 01, 2022 at 02:38:50PM +0800, Xuan Zhuo wrote: > > Introduce new helpers to implement queue reset and get queue reset > > status. > > > > https://github.com/oasis-tcs/virtio-spec/issues/124 > > https://github.com/oasis-tcs/virtio-spec/issues/139 > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> > > Acked-by: Jason Wang <jasowang@xxxxxxxxxx> > > --- > > drivers/virtio/virtio_pci_modern_dev.c | 39 ++++++++++++++++++++++++++ > > include/linux/virtio_pci_modern.h | 2 ++ > > 2 files changed, 41 insertions(+) > > > > diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c > > index fa2a9445bb18..869cb46bef96 100644 > > --- a/drivers/virtio/virtio_pci_modern_dev.c > > +++ b/drivers/virtio/virtio_pci_modern_dev.c > > @@ -3,6 +3,7 @@ > > #include <linux/virtio_pci_modern.h> > > #include <linux/module.h> > > #include <linux/pci.h> > > +#include <linux/delay.h> > > > > /* > > * vp_modern_map_capability - map a part of virtio pci capability > > @@ -474,6 +475,44 @@ void vp_modern_set_status(struct virtio_pci_modern_device *mdev, > > } > > EXPORT_SYMBOL_GPL(vp_modern_set_status); > > > > +/* > > + * vp_modern_get_queue_reset - get the queue reset status > > + * @mdev: the modern virtio-pci device > > + * @index: queue index > > + */ > > +int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index) > > +{ > > + struct virtio_pci_modern_common_cfg __iomem *cfg; > > + > > + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; > > + > > + vp_iowrite16(index, &cfg->cfg.queue_select); > > + return vp_ioread16(&cfg->queue_reset); > > +} > > +EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset); > > + > > Actually, this does not validate that the config structure is big > enough. So it can access some unrelated memory. Don't know whether > that's exploitable e.g. for CoCo but not nice, anyway. > Need to validate the size and disable reset if it's too small. static int vp_modern_disable_vq_and_reset(struct virtqueue *vq) { struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev); struct virtio_pci_modern_device *mdev = &vp_dev->mdev; struct virtio_pci_vq_info *info; unsigned long flags; -> if (!virtio_has_feature(vq->vdev, VIRTIO_F_RING_RESET)) return -ENOENT; vp_modern_set_queue_reset(mdev, vq->index); I checked VIRTIO_F_RING_RESET before call this. Do you mean, we should put the check to this function. Thanks. > > > > +/* > > + * vp_modern_set_queue_reset - reset the queue > > + * @mdev: the modern virtio-pci device > > + * @index: queue index > > + */ > > +void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index) > > +{ > > + struct virtio_pci_modern_common_cfg __iomem *cfg; > > + > > + cfg = (struct virtio_pci_modern_common_cfg __iomem *)mdev->common; > > + > > + vp_iowrite16(index, &cfg->cfg.queue_select); > > + vp_iowrite16(1, &cfg->queue_reset); > > + > > + while (vp_ioread16(&cfg->queue_reset)) > > + msleep(1); > > + > > + while (vp_ioread16(&cfg->cfg.queue_enable)) > > + msleep(1); > > +} > > +EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset); > > + > > /* > > * vp_modern_queue_vector - set the MSIX vector for a specific virtqueue > > * @mdev: the modern virtio-pci device > > diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h > > index 05123b9a606f..c4eeb79b0139 100644 > > --- a/include/linux/virtio_pci_modern.h > > +++ b/include/linux/virtio_pci_modern.h > > @@ -113,4 +113,6 @@ void __iomem * vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev, > > u16 index, resource_size_t *pa); > > int vp_modern_probe(struct virtio_pci_modern_device *mdev); > > void vp_modern_remove(struct virtio_pci_modern_device *mdev); > > +int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index); > > +void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index); > > #endif > > -- > > 2.31.0 >
