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Subject: Re: [PATCH net v1 3/3] [RFC] mac80211: ieee80211_store_ack_skb():
 make use of skb_clone_sk_optional()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Marc Kleine-Budde <mkl@pengutronix.de>
Cc:     Oleksij Rempel <o.rempel@pengutronix.de>,
        "David S. Miller" <davem@davemloft.net>,
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Date:   Tue, 23 Feb 2021 10:47:22 +0100
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On Mon, 2021-02-22 at 19:51 +0100, Marc Kleine-Budde wrote:
> On 22.02.2021 17:30:59, Johannes Berg wrote:
> > On Mon, 2021-02-22 at 16:12 +0100, Oleksij Rempel wrote:
> > > This code is trying to clone the skb with optional skb->sk. But this
> > > will fail to clone the skb if socket was closed just after the skb was
> > > pushed into the networking stack.
> > 
> > Which IMHO is completely fine. If we then still clone the SKB we can't
> > do anything with it, since the point would be to ... send it back to the
> > socket, but it's gone.
> 
> Ok, but why is the skb cloned if there is no socket linked in skb->sk?

Hm? There are two different ways to get here, one with and one without a
socket.

johannes