Re: [06/20] crypto: sha512 - reduce stack usage to safe number

From: Greg KH
Date: Wed Feb 01 2012 - 18:55:06 EST

On Thu, Feb 02, 2012 at 02:42:08AM +0300, Alexey Dobriyan wrote:
> On Wed, Feb 01, 2012 at 12:14:08PM -0800, Greg KH wrote:
> > @@ -87,38 +87,48 @@ sha512_transform(u64 *state, const u8 *i
> > u64 a, b, c, d, e, f, g, h, t1, t2;
> >
> > int i;
> > - u64 W[80];
> > + u64 W[16];
> This needs 3rd companion patch which does stack reduction even on i386.
> Patch which removes excessive loop unrolling and thus fixes the problem
> has been posted. Maybe there is some other way to maintain low stack
> space on i386 but I haven't found it.
> If you apply only 2, original bug will be fixed, but on at least i386
> stack usage could go in 900-byte region.

But this patch isn't in Linus's tree yet, right?

So, should I just drop this one for now (well both of them) or just wait
for the above referenced patch to hit Linus's tree and handle it then?


greg k-h
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