Re: [PATCH io_uring-6.18 1/1] io_uring: fix types for region size calulation

[Jens Axboe <axboe@kernel.dk>]

On 11/6/25 5:09 AM, Pavel Begunkov wrote:
> On 11/5/25 18:44, Jens Axboe wrote:
>> On 11/5/25 8:47 AM, Pavel Begunkov wrote:
>>> ->nr_pages is int, it needs type extension before calculating the region
>>> size.
>>>
>>> Fixes: a90558b36ccee ("io_uring/memmap: helper for pinning region pages")
>>> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
>>> ---
>>>   io_uring/memmap.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/io_uring/memmap.c b/io_uring/memmap.c
>>> index 2e99dffddfc5..fab79c7b3157 100644
>>> --- a/io_uring/memmap.c
>>> +++ b/io_uring/memmap.c
>>> @@ -135,7 +135,7 @@ static int io_region_pin_pages(struct io_ring_ctx *ctx,
>>>                   struct io_mapped_region *mr,
>>>                   struct io_uring_region_desc *reg)
>>>   {
>>> -    unsigned long size = mr->nr_pages << PAGE_SHIFT;
>>> +    unsigned long size = (size_t)mr->nr_pages << PAGE_SHIFT;
>>>       struct page **pages;
>>>       int nr_pages;
>>
>> Should probably consistently use a size_t, everywhere else does. Doesn't
>> matter here as io_pin_pages() does the right thing anyway.
> 
> I have a patch on the topic as I needed it myself, but didn't
> include it into the fix.

That's fine, better that way too imho.

-- 
Jens Axboe