From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: v2 [PATCH net-next 1/8] af_packet: Check return of dev_set_promiscuity/allmulti
Date: Tue, 01 Jul 2008 11:36:17 +0200
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References: <4869A251.108@cn.fujitsu.com> <4869A2D5.1010605@cn.fujitsu.com>
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Cc: "David S. Miller" <davem@davemloft.net>,
	NETDEV <netdev@vger.kernel.org>
To: Wang Chen <wangchen@cn.fujitsu.com>
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Wang Chen wrote:
> dev_set_promiscuity/allmulti might overflow.
> Commit: "netdevice: Fix promiscuity and allmulti overflow" in net-next makes
> dev_set_promiscuity/allmulti return error number if overflow happened.
> 
> In af_packet, we check all positive increment for promiscuity and allmulti
> to get error return.
> 
>  static void packet_dev_mclist(struct net_device *dev, struct packet_mclist *i, int what)
> @@ -1245,7 +1247,7 @@ static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
>  	i->count = 1;
>  	i->next = po->mclist;
>  	po->mclist = i;
> -	packet_dev_mc(dev, i, +1);
> +	err = packet_dev_mc(dev, i, 1);

Missing error handling. The packet_mclist is already initialized
and on the list here, which will result in deletion without
addition in packet_flush_mclist().