Re: [PATCH][next] afs: fix integer overflow when shifting 1 more than 32 places

From: Colin Ian King
Date: Wed Apr 11 2018 - 09:42:54 EST


On 11/04/18 14:39, David Howells wrote:
> Colin King <colin.king@xxxxxxxxxxxxx> wrote:
>
>> Shifting 1 (a 32 bit signed int) more than 32 places will overflow
>> the int, so explicitly use 1ULL to avoid this overflow.
>> ...
>> - mask = (1 << nr_slots) - 1;
>> + mask = (1ULL << nr_slots) - 1;
>
> nr_slots cannot be larger than 9, so what I wrote is actually fine and is more
> efficient on a 32-bit machine.

ok, sorry about the noise.

>
> David
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