| Message ID | 20230714182445.877168-1-eric.auger@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | hw/virtio-iommu: Fix potential OOB access in virtio_iommu_handle_command() | expand |
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c index 201127c488..4dcf1d5c62 100644 --- a/hw/virtio/virtio-iommu.c +++ b/hw/virtio/virtio-iommu.c @@ -728,13 +728,15 @@ static void virtio_iommu_handle_command(VirtIODevice *vdev, VirtQueue *vq) VirtIOIOMMU *s = VIRTIO_IOMMU(vdev); struct virtio_iommu_req_head head; struct virtio_iommu_req_tail tail = {}; - size_t output_size = sizeof(tail), sz; VirtQueueElement *elem; unsigned int iov_cnt; struct iovec *iov; void *buf = NULL; + size_t sz; for (;;) { + size_t output_size = sizeof(tail); + elem = virtqueue_pop(vq, sizeof(VirtQueueElement)); if (!elem) { return;
In the virtio_iommu_handle_command() when a PROBE request is handled, output_size takes a value greater than the tail size and on a subsequent iteration we can get a stack out-of-band access. Initialize the output_size on each iteration. The issue was found with ASAN. Credits to: Yiming Tao(Zhejiang University) Gaoning Pan(Zhejiang University) Fixes: 1733eebb9e7 ("virtio-iommu: Implement RESV_MEM probe request") Signed-off-by: Eric Auger <eric.auger@redhat.com> Reported-by: Mauro Matteo Cascella <mcascell@redhat.com> --- hw/virtio/virtio-iommu.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)