On Mon, 05 Feb 2024 19:26, Stefan Hajnoczi <stefa...@redhat.com> wrote:
Hanna Czenczek <hre...@redhat.com> noted that the array index in
virtio_blk_dma_restart_cb() is not bounds-checked:
g_autofree VirtIOBlockReq **vq_rq = g_new0(VirtIOBlockReq *, num_queues);
...
while (rq) {
VirtIOBlockReq *next = rq->next;
uint16_t idx = virtio_get_queue_index(rq->vq);
rq->next = vq_rq[idx];
^^^^^^^^^^
The code is correct because both rq->vq and vq_rq[] depend on
num_queues, but this is indirect and not 100% obvious. Add an assertion.
This sentence could be useful as an inline comment too.
Suggested-by: Hanna Czenczek <hre...@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com>
---
hw/block/virtio-blk.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index a0735a9bca..f3193f4b75 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -1209,6 +1209,7 @@ static void virtio_blk_dma_restart_cb(void *opaque, bool
running,
VirtIOBlockReq *next = rq->next;
uint16_t idx = virtio_get_queue_index(rq->vq);
+ assert(idx < num_queues);
rq->next = vq_rq[idx];
vq_rq[idx] = rq;
rq = next;
--
2.43.0
Reviewed-by: Manos Pitsidianakis <manos.pitsidiana...@linaro.org>