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Date:   Fri, 30 Sep 2022 14:14:10 +0800
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     George Cherian <gcherian@marvell.com>,
        "David S. Miller" <davem@davemloft.net>,
        David Daney <david.daney@cavium.com>,
        linux-crypto@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH v2] crypto: cavium - prevent integer overflow loading
 firmware
Message-ID: <YzaJMu191++1ptvq@gondor.apana.org.au>
References: <YygPj8aYTvApOQFB@kili>
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On Mon, Sep 19, 2022 at 09:43:27AM +0300, Dan Carpenter wrote:
> The "code_length" value comes from the firmware file.  If your firmware
> is untrusted realistically there is probably very little you can do to
> protect yourself.  Still we try to limit the damage as much as possible.
> Also Smatch marks any data read from the filesystem as untrusted and
> prints warnings if it not capped correctly.
> 
> The "ntohl(ucode->code_length) * 2" multiplication can have an
> integer overflow.
> 
> Fixes: 9e2c7d99941d ("crypto: cavium - Add Support for Octeon-tx CPT Engine")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> v2: The first code removed the " * 2" so it would have caused immediate
>     memory corruption and crashes.
> 
>     Also in version 2 I combine the "if (!mcode->code_size) {" check
>     with the overflow check for better readability.
> 
>  drivers/crypto/cavium/cpt/cptpf_main.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)

Patch applied.  Thanks.
-- 
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