vfio: Fix an incorrect break out of nested loop in iommu mapping code.

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Merge tag 'vfio-v3.12-rc5' of git://github.com/awilliam/linux-vfio

Pull vfio fix from Alex Williamson:
 "Fix an incorrect break out of nested loop in iommu mapping code"

* tag 'vfio-v3.12-rc5' of git://github.com/awilliam/linux-vfio:
  VFIO: vfio_iommu_type1: fix bug caused by break in nested loop
This commit is contained in:
Linus Torvalds 2013-10-14 18:11:28 -07:00
commit 1e52db6908

View file

@ -545,6 +545,8 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
long npage;
int ret = 0, prot = 0;
uint64_t mask;
struct vfio_dma *dma = NULL;
unsigned long pfn;
end = map->iova + map->size;
@ -587,8 +589,6 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
}
for (iova = map->iova; iova < end; iova += size, vaddr += size) {
struct vfio_dma *dma = NULL;
unsigned long pfn;
long i;
/* Pin a contiguous chunk of memory */
@ -597,16 +597,15 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
if (npage <= 0) {
WARN_ON(!npage);
ret = (int)npage;
break;
goto out;
}
/* Verify pages are not already mapped */
for (i = 0; i < npage; i++) {
if (iommu_iova_to_phys(iommu->domain,
iova + (i << PAGE_SHIFT))) {
vfio_unpin_pages(pfn, npage, prot, true);
ret = -EBUSY;
break;
goto out_unpin;
}
}
@ -616,8 +615,7 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
if (ret) {
if (ret != -EBUSY ||
map_try_harder(iommu, iova, pfn, npage, prot)) {
vfio_unpin_pages(pfn, npage, prot, true);
break;
goto out_unpin;
}
}
@ -672,9 +670,8 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
dma = kzalloc(sizeof(*dma), GFP_KERNEL);
if (!dma) {
iommu_unmap(iommu->domain, iova, size);
vfio_unpin_pages(pfn, npage, prot, true);
ret = -ENOMEM;
break;
goto out_unpin;
}
dma->size = size;
@ -685,16 +682,21 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
}
}
if (ret) {
struct vfio_dma *tmp;
iova = map->iova;
size = map->size;
while ((tmp = vfio_find_dma(iommu, iova, size))) {
int r = vfio_remove_dma_overlap(iommu, iova,
&size, tmp);
if (WARN_ON(r || !size))
break;
}
WARN_ON(ret);
mutex_unlock(&iommu->lock);
return ret;
out_unpin:
vfio_unpin_pages(pfn, npage, prot, true);
out:
iova = map->iova;
size = map->size;
while ((dma = vfio_find_dma(iommu, iova, size))) {
int r = vfio_remove_dma_overlap(iommu, iova,
&size, dma);
if (WARN_ON(r || !size))
break;
}
mutex_unlock(&iommu->lock);