Re: [mac80211] BUG_ON with current -git (4.8.0-11417-g24532f7)

From: Ard Biesheuvel
Date: Fri Oct 14 2016 - 04:48:34 EST


On 14 October 2016 at 09:42, Johannes Berg <johannes@xxxxxxxxxxxxxxxx> wrote:
> On Fri, 2016-10-14 at 09:41 +0100, Ard Biesheuvel wrote:
>
>> > I assume the stack buffer itself is not the problem here, but aad,
>> > which is allocated on the stack one frame up.
>> > Do we really need to revert the whole patch to fix that?
>>
>> Ah never mind, this is about 'odata'. Apologies, should have read
>> first
>
> Right, odata also goes into an sg list and further on.
>
> I think we should wait for Herbert to chime in before we do any further
> work though, perhaps he has any better ideas.
>

Do you have a reference for the sg_set_buf() call on odata?
crypto/ccm.c does not seem to have it (afaict), and the same problem
does not exist in the accelerated arm64 implementation. In the mean
time, I will try and see if we can move aad[] off the stack in the WPA
code.