diff options
-rw-r--r-- | lib/swiotlb.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/lib/swiotlb.c b/lib/swiotlb.c index db724ba7ebf6..1272b23e4769 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -301,6 +301,10 @@ map_single(struct device *hwdev, char *buffer, size_t size, int dir) start_dma_addr = virt_to_bus(io_tlb_start) & mask; offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; + + /* + * Carefully handle integer overflow which can occur when mask == ~0UL. + */ max_slots = mask + 1 ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); |