On Fri, Aug 17, 2018 at 5:17 PM, Russell King - ARM Linux
<li...@armlinux.org.uk> wrote:
> On Fri, Aug 17, 2018 at 02:40:19PM +0200, Daniel Borkmann wrote:
>> I'd have one potential bug suspicion, for the 4.18 one you were trying,
>> could you run with the below patch to see whether it would help?
>
> I think this is almost certainly the problem - looking at the history,
> it seems that the "-4" was assumed to be part of the scratch stuff in
> commit 38ca93060163 ("bpf, arm32: save 4 bytes of unneeded stack space")
> but it isn't - it's because "off" of zero refers to the top word in the
> stack (iow at STACK_SIZE-4).I can confirm that patch fixes the problem I was seeing. Peter
