On Mon Apr 29, 2024 at 7:57 PM EEST, Stefan Berger wrote:
>
>
> On 4/29/24 12:47, Jarkko Sakkinen wrote:
> > On Mon Apr 29, 2024 at 7:13 PM EEST, Stefan Berger wrote:
> >> Prevent ecc_digits_from_bytes from reading too many bytes from the input
> >> byte array in case an insufficient number of bytes is provided to fill the
> >> output digit array of ndigits. Therefore, initialize the most significant
> >> digits with 0 to avoid trying to read too many bytes later on. Convert the
> >> function into a regular function since it is getting too big for an inline
> >> function.
> >>
> >> If too many bytes are provided on the input byte array the extra bytes
> >> are ignored since the input variable 'ndigits' limits the number of digits
> >> that will be filled.
> >>
> >> Fixes: d67c96fb97b5 ("crypto: ecdsa - Convert byte arrays with key coordinates to digits")
> >> Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>
> >>
> >> ---
> >>
> >> v2:
> >> - un-inline function
> >> - use memset
> >> ---
> >> crypto/ecc.c | 22 ++++++++++++++++++++++
> >> include/crypto/internal/ecc.h | 15 ++-------------
> >> 2 files changed, 24 insertions(+), 13 deletions(-)
> >>
> >> diff --git a/crypto/ecc.c b/crypto/ecc.c
> >> index c1d2e884be1e..fe761256e335 100644
> >> --- a/crypto/ecc.c
> >> +++ b/crypto/ecc.c
> >> @@ -68,6 +68,28 @@ const struct ecc_curve *ecc_get_curve(unsigned int curve_id)
> >> }
> >> EXPORT_SYMBOL(ecc_get_curve);
> >>
> >
> > Just a minor nit:
> >
> > For exported symbol you need to document the function,including
> > the parameters [1].
>
> Like other functions, the ecc_digits_from_bytes also still/already has
> the documentation in the header file:
>
> /**
> * ecc_digits_from_bytes() - Create ndigits-sized digits array from
> byte array
> * @in: Input byte array
> * @nbytes Size of input byte array
> * @out Output digits array
> * @ndigits: Number of digits to create from byte array
> */
> void ecc_digits_from_bytes(const u8 *in, unsigned int nbytes,
> u64 *out, unsigned int ndigits);
>
> Should be ok?
I think it should be OK, or at least documentation has not denied
doing that and gives example how to import from header files:
https://www.kernel.org/doc/html/latest/doc-guide/kernel-doc.html
Just had not encountered that before so that said
Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
BR, Jarkko
