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Subject: Re: crypto: algif_hash: creating 0 sized array in hash_accept
To: Herbert Xu <herbert@gondor.apana.org.au>
References: <56A6119C.1080203@oracle.com>
 <20160125135846.GB8256@gondor.apana.org.au> <56A77411.5030209@oracle.com>
 <20160126140724.GA22685@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>,
        "open list:CRYPTO API" <linux-crypto@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
From: Sasha Levin <sasha.levin@oracle.com>
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Date: Tue, 26 Jan 2016 09:30:54 -0500
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On 01/26/2016 09:07 AM, Herbert Xu wrote:
> On Tue, Jan 26, 2016 at 08:26:41AM -0500, Sasha Levin wrote:
>> >
>> > This seems to be happening with "digest_null".
> In that case this is expected as digest_null obviously has no
> state.  So why is a zero-length array disallowed by ubsan?

The C spec forbids it, so ubsan complains :)


Thanks,
Sasha