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Date:   Mon, 27 Apr 2020 11:20:54 -0700 (PDT)
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To:     xiyuyang19@fudan.edu.cn
Cc:     andrew.hendry@gmail.com, kuba@kernel.org, tanxin.ctf@gmail.com,
        gregkh@linuxfoundation.org, allison@lohutok.net,
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        yuanxzhang@fudan.edu.cn, kjlu@umn.edu
Subject: Re: [PATCH v2] net/x25: Fix x25_neigh refcnt leak when x25
 disconnect
From:   David Miller <davem@davemloft.net>
In-Reply-To: <1587819994-40137-1-git-send-email-xiyuyang19@fudan.edu.cn>
References: <1587819994-40137-1-git-send-email-xiyuyang19@fudan.edu.cn>
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From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Date: Sat, 25 Apr 2020 21:06:25 +0800

> x25_connect() invokes x25_get_neigh(), which returns a reference of the
> specified x25_neigh object to "x25->neighbour" with increased refcnt.
> 
> When x25 connect success and returns, the reference still be hold by
> "x25->neighbour", so the refcount should be decreased in
> x25_disconnect() to keep refcount balanced.
> 
> The reference counting issue happens in x25_disconnect(), which forgets
> to decrease the refcnt increased by x25_get_neigh() in x25_connect(),
> causing a refcnt leak.
> 
> Fix this issue by calling x25_neigh_put() before x25_disconnect()
> returns.
> 
> Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>

Applied.