[PATCH] virtio_pci_modern: validate features

["Michael S. Tsirkin" <mst@redhat.com>]

Spec says devices must set VIRTIO_1 feature bit.
Fail gracefully if they don't.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 drivers/virtio/virtio_pci_modern.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 17f0228..a8fd267 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -570,6 +570,7 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
 	int err, common, isr, notify, device;
 	u32 notify_length;
 	u32 notify_offset;
+	u64 features;
 
 	check_offsets();
 
@@ -676,12 +677,19 @@ int virtio_pci_modern_probe(struct virtio_pci_device *vp_dev)
 		vp_dev->vdev.config = &virtio_pci_config_nodev_ops;
 	}
 
+	features = vp_get_features(vdev);
+	if (!features & (1ULL << VIRTIO_F_VERSION_1))
+		goto err_valid_features;
+
 	vp_dev->config_vector = vp_config_vector;
 	vp_dev->setup_vq = setup_vq;
 	vp_dev->del_vq = del_vq;
 
 	return 0;
 
+err_valid_features:
+	if (vp_dev->device)
+		pci_iounmap(pci_dev, vp_dev->device);
 err_map_device:
 	if (vp_dev->notify_base)
 		pci_iounmap(pci_dev, vp_dev->notify_base);
-- 
MST