On Fri, Jan 22, 2016 at 12:59:47PM +1100, Alexey Kardashevskiy wrote:

On 01/22/2016 11:42 AM, David Gibson wrote:

quoted

On Thu, Jan 21, 2016 at 06:39:32PM +1100, Alexey Kardashevskiy wrote:

[snip]

quoted

quoted

+	if ((ioba & mask) || (idx + npages > size))

It doesn't matter for the current callers, but you should check for
overflow in idx + npages as well.

npages can be only 1..512 and this is checked in H_PUT_TCE/etc handlers.
idx is 52bit long max.
And this is not going to change because H_PUT_TCE_INDIRECT will always be
limited by 512 (or one 4K page).

Do I still need the overflow check here?

You could add "|| npages > TCES_PER_PAGE" and that would make it clear
that there can't be any overflow, and it should get removed by the
compiler for the calls with constant npages.

Paul.