From: Herbert Xu <herbert@gondor.apana.org.au>
To: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>,
Xufeng Zhang <yunbo.xufeng@linux.alibaba.com>,
linux-kernel@vger.kernel.org,
Linux Crypto Mailing List <linux-crypto@vger.kernel.org>
Subject: [PATCH] lib/mpi: Remove unused scalar_copied
Date: Thu, 8 Oct 2020 16:58:18 +1100 [thread overview]
Message-ID: <20201008055818.GB9813@gondor.apana.org.au> (raw)
In-Reply-To: <20200928182438.GA11739@embeddedor>
On Mon, Sep 28, 2020 at 01:24:38PM -0500, Gustavo A. R. Silva wrote:
>
> I'm reporting the following bug detected by Coverity:
>
> The _scalar_copied_ variable is set to 0 at
>
> lib/mpi/ec.c:1255:
> 1255 int scalar_copied = 0;
>
> and it is never updated before reaching the code below:
>
> lib/mpi/ec.c:1317
> 1317 if (scalar_copied)
> 1318 mpi_free(scalar);
>
> This code was introduced by commit d58bb7e55a8a ("lib/mpi: Introduce ec
> implementation to MPI library")
>
> Any ideas on what's the right solution for this?
I think it should be removed.
---8<---
The scalar_copied variable is not as the scalar is never copied
in that block. This patch removes it.
Fixes: d58bb7e55a8a ("lib/mpi: Introduce ec implementation to...")
Reported-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/lib/mpi/ec.c b/lib/mpi/ec.c
index c21470122dfc..40f5908e57a4 100644
--- a/lib/mpi/ec.c
+++ b/lib/mpi/ec.c
@@ -1252,7 +1252,6 @@ void mpi_ec_mul_point(MPI_POINT result,
MPI_POINT q1, q2, prd, sum;
unsigned long sw;
mpi_size_t rsize;
- int scalar_copied = 0;
/* Compute scalar point multiplication with Montgomery Ladder.
* Note that we don't use Y-coordinate in the points at all.
@@ -1314,8 +1313,6 @@ void mpi_ec_mul_point(MPI_POINT result,
point_free(&p2);
point_free(&p1_);
point_free(&p2_);
- if (scalar_copied)
- mpi_free(scalar);
return;
}
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
prev parent reply other threads:[~2020-10-08 5:58 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-28 18:24 Reporting bug in mpi_ec_mul_point() Gustavo A. R. Silva
2020-10-08 5:58 ` Herbert Xu [this message]
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