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From: Martin KaFai Lau <kafai@fb.com>
Subject: Re: [PATCH net 3/3] ipv6: Fix dst_entry refcnt bugs in ip6_tunnel
Date: Tue, 1 Sep 2015 13:55:05 -0700
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Cc: netdev <netdev@vger.kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Tue, Sep 01, 2015 at 01:14:20PM -0700, Eric Dumazet wrote:
> It should not be a problem. refcnt is taken when/if necessary (skb
> queued on a qdisc for example)
>
> We have other uses of skb_dst_set_noref()
>
> Please describe the problem ?
The current ip6_tnl_dst_get() does not take the dst refcnt.

If the dst is released after ip6_tnl_dst_get() and before
skb_dst_set_noref(), would it cause an issue?