vfio: convert to 128 bit arithmetic calculations when adding mem regions

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.williamson@redhat.com>
Signed-off-by: Bandan Das <bsd@redhat.com>
[missed (end - 1) on 2nd trace call, move llsize closer to use]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Bandan Das 2016-03-23 20:37:25 -04:00 committed by Alex Williamson
parent b68a80139e
commit 55efcc537d

View File

@ -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
@ -395,13 +395,16 @@ static void vfio_listener_region_add(MemoryListener *listener,
section->offset_within_region +
(iova - section->offset_within_address_space);
trace_vfio_listener_region_add_ram(iova, end - 1, vaddr);
trace_vfio_listener_region_add_ram(iova, end, vaddr);
ret = vfio_dma_map(container, iova, end - iova, vaddr, section->readonly);
llsize = int128_sub(llend, int128_make64(iova));
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;
}