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Date:   Thu, 4 Jun 2020 16:18:11 +1000
From:   Herbert Xu <herbert@gondor.apana.org.au>
To:     Zhangfei Gao <zhangfei.gao@linaro.org>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        wangzhou1 <wangzhou1@hisilicon.com>,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org,
        kbuild-all@lists.01.org
Subject: Re: [PATCH] crypto: hisilicon - fix strncpy warning with strlcpy
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On Thu, Jun 04, 2020 at 02:10:37PM +0800, Zhangfei Gao wrote:
>
> > Should this even allow truncation? Perhaps it'd be better to fail
> > in case of an overrun?
> I think we do not need consider overrun, since it at most copy size-1 bytes
> to dest.
> From the manual: strlcpy()
> ?????? This? function? is? similar? to? strncpy(), but it copies at most
> size-1 bytes to dest, always adds a terminating null
> ?????? byte,
> And simple tested with smaller SIZE of interface.name,? only SIZE-1 is
> copied, so it is safe.
> -#define UACCE_MAX_NAME_SIZE??? 64
> +#define UACCE_MAX_NAME_SIZE??? 4

That's not what I meant.  As it is if you do exceed the limit the
name is silently truncated.  Wouldn't it be better to fail the
allocation instead?

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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