Re: Fwd: [crypto:master 60/60] arch/x86/crypto/ghash-clmulni-intel_glue.c:71:25: sparse: cast to restricted __be64

["gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>]

On Fri, Apr 11, 2014 at 09:48:42PM +0200, Ard Biesheuvel wrote:
> On 11 April 2014 18:03, gregkh@linuxfoundation.org
> <gregkh@linuxfoundation.org> wrote:
> > On Fri, Apr 04, 2014 at 10:11:19AM +0200, Ard Biesheuvel wrote:
> >> Greg,
> >>
> >> This pertains to commit 8ceee72808d1 (crypto: ghash-clmulni-intel -
> >> use C implementation for setkey()) that has been pulled by Linus
> >> during the current merge window.
> >>
> >> It is missing two things:
> >> - a cc to stable annotation
> >> - a fix for the sparse warning below (change cast from __be64 to __force __be64)
> >>
> >> The reason for cc'ing stable on this patch is that it fixes a
> >> potential data corruption issue where the ghash setkey() method uses
> >> SSE registers without calling kernel_fpu_begin() first. This issue was
> >> introduced by 0e1227d356e9b (crypto: ghash - Add PCLMULQDQ accelerated
> >> implementation).
> >>
> >> So how would you like to proceed with this? Should I propose a new
> >> patch somewhere?
> >
> > No problem, I'll apply this as-is.  But it doesn't apply to the
> > 3.4-stable tree cleanly, can you send me a backported version if it's
> > still needed there as well?
> >
> 
> Yes, the code was broken from the start. 3.4 version is attached, the
> only difference is the missing ENDPROC() at the end of the asm file.
> 
> In the mean time, Herbert has submitted a fix for the sparse warning,
> but we settled on a different fix than I had suggested before.
> https://git.kernel.org/cgit/linux/kernel/git/herbert/cryptodev-2.6.git/commit/?id=0ea481466d1c
> 
> Note that this code has not been tested (not by me, at least), so I
> wouldn't suggest you take it straight away, but if you care about the
> sparse warning, we could add a cc stable to it as well, I suppose.

No, I don't care about a sparse warning, unless it's fixing a real bug.

I'll queue this up for the next 3.4 release after the one that happens
this weekend, thanks.

greg k-h