From mboxrd@z Thu Jan  1 00:00:00 1970
From: YOSHIFUJI Hideaki / =?iso-2022-jp?B?GyRCNUhGIzFRTEAbKEI=?=
	<yoshfuji@linux-ipv6.org>
Subject: Re: [PATCH][MCAST]IPv6: Check packet size when process Multicast
 Address and Source Specific Query
Date: Mon, 31 Oct 2005 14:27:17 +0900 (JST)
Message-ID: <20051031.142717.40152885.yoshfuji@linux-ipv6.org>
References: <4365A995.3050404@21cn.com>
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Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	dlstevens@us.ibm.com, yoshfuji@linux-ipv6.org
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In article <4365A995.3050404@21cn.com> (at Mon, 31 Oct 2005 13:20:21 +0800), Yan Zheng <yanzheng@21cn.com> says:

> 
> Signed-off-by: Yan Zheng <yanzheng@21cn.com>
> 
> Index: net/ipv6/mcast.c
> ================================================================================
> --- linux-2.6.14/net/ipv6/mcast.c	2005-10-30 23:09:33.000000000 +0800
> +++ linux/net/ipv6/mcast.c	2005-10-31 13:13:10.000000000 +0800
> @@ -1156,7 +1156,12 @@ int igmp6_event_query(struct sk_buff *sk
>  			return 0;
>  		}
>  		/* mark sources to include, if group & source-specific */
> -		mark = mlh2->nsrcs != 0;
> +		if (mlh2->nsrcs != 0) {
> +			if (!pskb_may_pull(skb, mlh2->nsrcs * sizeof(struct in6_addr) +
> +				(sizeof(struct mld2_query) - sizeof(struct icmp6hdr))))
> +				return -EINVAL;
> +			mark = 1;
> +		}
>  	} else {
>  		in6_dev_put(idev);
>  		return -EINVAL;

You cannot continue using mlh2, local copy of skb->h.raw
after pskb_may_pull(). Please refresh it.

--yoshfuji