From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexey Dobriyan <adobriyan@gmail.com>
Subject: Re: [PATCH net-next] net: ndisc.c: reduce size of
 __ndisc_fill_addr_option()
Date: Sat, 27 May 2017 18:15:14 +0300
Message-ID: <20170527151514.GA3347@avx2>
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Cc: netdev@vger.kernel.org, davem@davemloft.net
To: Linyu.Yuan@alcatel-sbell.com.cn
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> --- a/net/ipv6/ndisc.c
> +++ b/net/ipv6/ndisc.c
> @@ -148,17 +148,18 @@ void __ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data,

>  	space -= data_len;
> -	if (space > 0)
> -		memset(opt, 0, space);
> +
> +	memset(opt, 0, space);

This can't be right.

And what size are you reducing?