Message-ID: <c0986327-71b5-0d8e-a126-5f9f632cc6af@linux.alibaba.com>
Date:   Tue, 31 Jan 2023 17:39:50 +0800
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Subject: Re: [PATCH] crypto: arm64/sm4 - Fix possible crash in GCM cryption
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To:     Herbert Xu <herbert@gondor.apana.org.au>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>, linux-crypto@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Ard Biesheuvel <ardb@kernel.org>
References: <20230118141928.48136-1-tianjia.zhang@linux.alibaba.com>
 <Y8gIC8Yn/E8Kwtf0@gondor.apana.org.au>
 <c7dbadbf-dade-fb1e-bda3-d23d567c620f@linux.alibaba.com>
 <Y9d8pfRQADxIhLIB@gondor.apana.org.au> <Y9eHXVyiSk0b+ovp@gondor.apana.org.au>
From:   Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
In-Reply-To: <Y9eHXVyiSk0b+ovp@gondor.apana.org.au>
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Hi Herbert,

On 1/30/23 5:01 PM, Herbert Xu wrote:
> On Mon, Jan 30, 2023 at 04:15:33PM +0800, Herbert Xu wrote:
>>
>> Actually I think there is a serious bug here.  If you're doing an
>> empty message, you must not call skcipher_walk_done as that may
>> then free random uninitialised stack memory.
> 
> Hah, I had forgotten that this thread started with your patch
> to fix this exact bug :)
> 
> Could you confirm that you did copy this from ccm?
> 
> It would be nice if you could rewrite your loop in a form similar
> to my patch to ccm.
> 
> Thanks,

These codes are copied from gcm and ccm at the same time. I am not sure
which has more components, but I will rewrite the gcm and ccm encryption
loop of sm4 as soon as possible.

Cheers,
Tianjia