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From: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Date: Thu, 24 Nov 2016 14:22:58 +0300
Message-ID: <CAPAsAGx5Kmb4k1pyUn_vgSy+rhjfcWAadFerjBpsH00Ne3HCAA@mail.gmail.com>
Subject: Re: [PATCH 2/2] MPI: Fix mpi_powm() when exponent is 0 and the result
 has no limbs
To: David Howells <dhowells@redhat.com>
Cc: jmorris@namei.org, Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>, stable@vger.kernel.org,
        linux-security-module@vger.kernel.org, keyrings@vger.kernel.org,
        linux-ima-devel@lists.sourceforge.net
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2016-11-24 14:17 GMT+03:00 David Howells <dhowells@redhat.com>:
> David Howells <dhowells@redhat.com> wrote:
>
>> +             if (!rp) {
>> +                     if (mpi_resize(res, 1) < 0)
>
> This is better done with RESIZE_IF_NEEDED().
>

mpi_resize() is equal to RESIZE_IF_NEEDED(), it also checks for allocated space:

int mpi_resize(MPI a, unsigned nlimbs)
{
....
   if (nlimbs <= a->alloced)
    return 0; /* no need to do it */



> David