vfio_listener_region_add for a iommu mr results in an overflow assert since iommu memory region is initialized with UINT64_MAX. Convert calculations to 128 bit arithmetic for iommu memory regions and let int128_get64 assert for non iommu regions if there's an overflow.
Suggested-by: Alex Williamson <alex.william...@redhat.com> Signed-off-by: Bandan Das <b...@redhat.com> --- v2: Just reuse @end (as hwaddr) for the end address Remove white space changes Extend 128 bit arithmetic ops upto the point vfio_dma_map is called Minor changes to commit message v1: This is v2 of http://patchwork.ozlabs.org/patch/600364/ hw/vfio/common.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) diff --git a/hw/vfio/common.c b/hw/vfio/common.c index fb588d8..ca05c87 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -323,7 +323,7 @@ static void vfio_listener_region_add(MemoryListener *listener, { VFIOContainer *container = container_of(listener, VFIOContainer, listener); hwaddr iova, end; - Int128 llend; + Int128 llend, llsize; void *vaddr; int ret; @@ -349,12 +349,12 @@ static void vfio_listener_region_add(MemoryListener *listener, if (int128_ge(int128_make64(iova), llend)) { return; } - end = int128_get64(llend); + end = int128_get64(int128_sub(llend, int128_one())); - if ((iova < container->min_iova) || ((end - 1) > container->max_iova)) { + if ((iova < container->min_iova) || (end > container->max_iova)) { error_report("vfio: IOMMU container %p can't map guest IOVA region" " 0x%"HWADDR_PRIx"..0x%"HWADDR_PRIx, - container, iova, end - 1); + container, iova, end); ret = -EFAULT; goto fail; } @@ -364,7 +364,7 @@ static void vfio_listener_region_add(MemoryListener *listener, if (memory_region_is_iommu(section->mr)) { VFIOGuestIOMMU *giommu; - trace_vfio_listener_region_add_iommu(iova, end - 1); + trace_vfio_listener_region_add_iommu(iova, end); /* * FIXME: We should do some checking to see if the * capabilities of the host VFIO IOMMU are adequate to model @@ -389,6 +389,8 @@ static void vfio_listener_region_add(MemoryListener *listener, return; } + llsize = int128_sub(llend, int128_make64(iova)); + /* Here we assume that memory_region_is_ram(section->mr)==true */ vaddr = memory_region_get_ram_ptr(section->mr) + @@ -397,11 +399,12 @@ static void vfio_listener_region_add(MemoryListener *listener, trace_vfio_listener_region_add_ram(iova, end - 1, vaddr); - ret = vfio_dma_map(container, iova, end - iova, vaddr, section->readonly); + ret = vfio_dma_map(container, iova, int128_get64(llsize), + vaddr, section->readonly); if (ret) { error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", " "0x%"HWADDR_PRIx", %p) = %d (%m)", - container, iova, end - iova, vaddr, ret); + container, iova, int128_get64(llsize), vaddr, ret); goto fail; } -- 2.5.0