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

[Andy Lutomirski]

On Wed, Oct 12, 2016 at 7:22 AM, Johannes Berg
<johannes@xxxxxxxxxxxxxxxx> wrote:
>
>> > Can you elaborate on how exactly it kills your system?
>>
>> the last time I saw it it was a NULL deref at
>> ieee80211_aes_ccm_decrypt.
>
> Hm. I was expecting something within the crypto code would cause the
> crash, this seems strange.
>
> Anyway, I'm surely out of my depth wrt. the actual cause. Something
> like the patch below probably works around it, but it's horribly
> inefficient due to the locking and doesn't cover CMAC/GMAC either.

In a pinch, I have these patches sitting around:

https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/commit/?h=x86/vmap_stack&id=0a39cfa6fbb5d5635c85253cc7d6b44b54822afd
https://git.kernel.org/cgit/linux/kernel/git/luto/linux.git/commit/?h=x86/vmap_stack&id=bf8cfa200b5a01383ea39fc8ce2f32909767baa8

I don't like them, though.  I think it's rather silly that we can't
just pass virtual addresses to the crypto code.