virtio: mmio-v1: Validate queue PFN (3fc92a96) · Commits · 戴 / test

virtio-mmio with virtio-v1 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> Signed-off-by:

Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_mmio.c

+18 −2

Original line number	Diff line number	Diff line
		@@ -397,9 +397,23 @@ static struct virtqueue vm_setup_vq(struct virtio_device vdev, unsigned index,
		/* Activate the queue */
		writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM);
		if (vm_dev->version == 1) {
		u64 q_pfn = virtqueue_get_desc_addr(vq) >> PAGE_SHIFT;

		/*
		* virtio-mmio v1 uses a 32bit QUEUE PFN. If we have something
		* that doesn't fit in 32bit, fail the setup rather than
		* pretending to be successful.
		*/
		if (q_pfn >> 32) {
		dev_err(&vdev->dev,
		"platform bug: legacy virtio-mmio must not be used with RAM above 0x%llxGB\n",
		0x1ULL << (32 + PAGE_SHIFT - 30));
		err = -E2BIG;
		goto error_bad_pfn;
		}

		writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN);
		writel(virtqueue_get_desc_addr(vq) >> PAGE_SHIFT,
		vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
		writel(q_pfn, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
		} else {
		u64 addr;

		@@ -430,6 +444,8 @@ static struct virtqueue vm_setup_vq(struct virtio_device vdev, unsigned index,

		return vq;

		error_bad_pfn:
		vring_del_virtqueue(vq);
		error_new_virtqueue:
		if (vm_dev->version == 1) {
		writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);

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