If an untrusted device neogitates BLK_F_MQ but advertises a zero num_queues, the driver may end up trying to allocating zero size buffers where ZERO_SIZE_PTR is returned which may pass the checking against the NULL. This will lead unexpected results.
Fixing this by failing the probe in this case. Cc: Paolo Bonzini <[email protected]> Cc: Stefan Hajnoczi <[email protected]> Cc: Stefano Garzarella <[email protected]> Signed-off-by: Jason Wang <[email protected]> --- drivers/block/virtio_blk.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 9b3bd083b411..10bc0879e618 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -497,6 +497,10 @@ static int init_vq(struct virtio_blk *vblk) &num_vqs); if (err) num_vqs = 1; + if (!err && !num_vqs) { + dev_err(&vdev->dev, "MQ advertisted but zero queues reported\n"); + return -EINVAL; + } num_vqs = min_t(unsigned int, nr_cpu_ids, num_vqs); -- 2.25.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
