From: xiongweimin <[email protected]> Reject unmap requests with size == 0 to prevent iova + size - 1 from underflowing to U64_MAX, which would incorrectly unmap the entire IOTLB range.
This fix also covers the error rollback path in vhost_vdpa_va_map: when the first VMA lookup fails, map_iova equals iova, resulting in a zero-size unmap that would otherwise clear the whole IOTLB. Signed-off-by: xiongweimin <[email protected]> --- drivers/vhost/vdpa.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index bb96b1aa5..f49bf1cfb 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -1035,6 +1035,9 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v, const struct vdpa_config_ops *ops = vdpa->config; u32 asid = iotlb_to_asid(iotlb); + if (!size) + return; + vhost_vdpa_iotlb_unmap(v, iotlb, iova, iova + size - 1, asid); if (ops->set_map) { -- 2.39.3
