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Date:   Sat, 18 Apr 2020 13:26:14 -0700 (PDT)
Message-Id: <20200418.132614.92642620154751485.davem@davemloft.net>
To:     xiyuyang19@fudan.edu.cn
Cc:     jmaloy@redhat.com, ying.xue@windriver.com, kuba@kernel.org,
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        kjlu@umn.edu, tanxin.ctf@gmail.com
Subject: Re: [PATCH] tipc: Fix potential tipc_node refcnt leak in tipc_rcv
From:   David Miller <davem@davemloft.net>
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From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Date: Wed, 15 Apr 2020 16:40:28 +0800

> tipc_rcv() invokes tipc_node_find() twice, which returns a reference of
> the specified tipc_node object to "n" with increased refcnt.
> 
> When tipc_rcv() returns or a new object is assigned to "n", the original
> local reference of "n" becomes invalid, so the refcount should be
> decreased to keep refcount balanced.
> 
> The issue happens in some paths of tipc_rcv(), which forget to decrease
> the refcnt increased by tipc_node_find() and will cause a refcnt leak.
> 
> Fix this issue by calling tipc_node_put() before the original object
> pointed by "n" becomes invalid.
> 
> Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>

Applied and queued up for -stable.