Re: [PATCH v5 01/12] crypto: ecdsa - Convert byte arrays with key coordinates to digits

[Stefan Berger]

On 3/8/24 03:41, Lukas Wunner wrote:
> On Wed, Mar 06, 2024 at 05:22:46PM -0500, Stefan Berger wrote:
> > +static inline void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
> > +					 u64 *out, unsigned int ndigits)
> > +{
> > +	unsigned int o = nbytes & 7;
> > +	u64 msd = 0;
>
> My sincere apologies, I made a mistake when I proposed this:
> It needs to be __be64 instead of u64...
>
> > +
> > +	if (o) {
> > +		memcpy((u8 *)&msd + sizeof(msd) - o, in, o);
> > +		out[--ndigits] = be64_to_cpu(msd);
> > +		in += o;
> > +	}
>
> ...otherwise sparse complains:
>
>      crypto/ecdsa.c: note: in included file:
>      >> include/crypto/internal/ecc.h:74:34: sparse: sparse: cast to restricted __be64
>      >> include/crypto/internal/ecc.h:74:34: sparse: sparse: cast to restricted __be64
>      [...]
>      66	static inline void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
>      67						 u64 *out, unsigned int ndigits)
>      68	{
>      69		unsigned int o = nbytes & 7;
>      70		u64 msd = 0;
>      71	
>      72		if (o) {
>      73			memcpy((u8 *)&msd + sizeof(msd) - o, in, o);
>    > 74			out[--ndigits] = be64_to_cpu(msd);
>      75			in += o;
>      76		}
>      77		ecc_swap_digits(in, out, ndigits);
>      78	}
>      79	
>
> 0-day alerted me about this, it's monitoring my GitHub repo and
> I've got your patches on one of my development branches.

Thanks. Fixed.

> Thanks,
>
> Lukas