diff --git a/drivers/of/address.c b/drivers/of/address.c index 6c40f96a1961..26f7fc3d7599 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -185,17 +185,15 @@ static u64 of_bus_pci_map(__be32 *addr, const __be32 *range, int na, int ns, static int __of_address_resource_bounds(struct resource *r, u64 start, u64 size) { - u64 end = start; - if (overflows_type(start, r->start)) return -EOVERFLOW; - if (size && check_add_overflow(end, size - 1, &end)) - return -EOVERFLOW; - if (overflows_type(end, r->end)) - return -EOVERFLOW; r->start = start; - r->end = end; + + if (!size) + r->end = wrapping_sub(typeof(r->end), r->start, 1); + else if (size && check_add_overflow(r->start, size - 1, &r->end)) + return -EOVERFLOW; return 0; }