Ok， I'll explain it in the next version of patches. Regards， Hongbo Eric Biggers <ebiggers@xxxxxxxxxx> 于2021年5月18日周二 上午5:29写道： > > On Thu, May 13, 2021 at 02:49:03PM +0000, herberthbli(李弘博) wrote: > > 在 2021/5/13 3:08, Eric Biggers 写道: > > > > On Wed, May 12, 2021 at 10:04:09PM +0800, Hongbo Li wrote: > > > > > > From: Hongbo Li <herberthbli@xxxxxxxxxxx><mailto:herberthbli@xxxxxxxxxxx> > > > > We should set the additional space to 0 in mpi_resize(). > > So use kcalloc() instead of kmalloc_array(). > > > > Signed-off-by: Hongbo Li <herberthbli@xxxxxxxxxxx><mailto:herberthbli@xxxxxxxxxxx> > > > > > > > > Is this fixing something, and if so what? > > > > - Eric > > > > > > > > In lib/mpi/ec.c: > > > > /**************** > > * Resize the array of A to NLIMBS. the additional space is cleared > > * (set to 0) [done by m_realloc()] > > */ > > int mpi_resize(MPI a, unsigned nlimbs) > > > > Like the comment of kernel's mpi_resize(), the additional space need to set to 0, > > but when a->d is not NULL, it does not set. > > > > The kernel's mpi lib is from libgcrypt, the mpi resize in libgcrypt is _gcry_mpi_resize() > > which set the additional space to 0. > > > > This issue will cause add_points_edwards() get a wrong result, and lead to a failed > > eddsa verification. > > > > That sounds like it's fixing an existing bug, regardless of the ed25519 support. > If that's indeed the case, what is the impact of that bug, and what commit is it > fixing? Please explain in the commit message and not just email. > > - Eric
