From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: [PATCH][NET_SCHED] cls_u32: refcounting fix for u32_delete()
Date: Fri, 11 Apr 2008 14:55:27 +0200
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References: <20080411124519.GA2701@ff.dom.local>
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Cc: David Miller <davem@davemloft.net>,
	Jamal Hadi Salim <hadi@cyberus.ca>, netdev@vger.kernel.org
To: Jarek Poplawski <jarkao2@gmail.com>
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Jarek Poplawski wrote:
> [NET_SCHED] cls_u32: refcounting fix for u32_delete()
> 
> @@ -441,8 +443,10 @@ static int u32_delete(struct tcf_proto *tp, unsigned long arg)
>  	if (tp->root == ht)
>  		return -EINVAL;
>  
> -	if (--ht->refcnt == 0)
> +	if (ht->refcnt == 1) {
> +		ht->refcnt--;
>  		u32_destroy_hnode(tp, ht);
> +	}
>  

Shouldn't the refcount be decremented unconditionally?
Otherwise I'd suggest to reject the removal if refcnt > 1,
but silently doing nothing doesn't seem right.