iommu/amd: Handle integer overflow in dma_ops_area_alloc

Handle this case to make sure boundary_size does not become
0 and trigger a BUG_ON later.

Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Joerg Roedel 2015-05-27 09:26:09 +02:00
parent d4b0366484
commit e6aabee05f

View File

@ -1699,14 +1699,16 @@ static unsigned long dma_ops_area_alloc(struct device *dev,
unsigned long next_bit = dom->next_address % APERTURE_RANGE_SIZE;
int max_index = dom->aperture_size >> APERTURE_RANGE_SHIFT;
int i = start >> APERTURE_RANGE_SHIFT;
unsigned long boundary_size;
unsigned long boundary_size, mask;
unsigned long address = -1;
unsigned long limit;
next_bit >>= PAGE_SHIFT;
boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
PAGE_SIZE) >> PAGE_SHIFT;
mask = dma_get_seg_boundary(dev);
boundary_size = mask + 1 ? ALIGN(mask + 1, PAGE_SIZE) >> PAGE_SHIFT :
1UL << (BITS_PER_LONG - PAGE_SHIFT);
for (;i < max_index; ++i) {
unsigned long offset = dom->aperture[i]->offset >> PAGE_SHIFT;