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Date:   Mon, 27 Apr 2020 11:23:10 -0700 (PDT)
Message-Id: <20200427.112310.1116562235104207694.davem@davemloft.net>
To:     xiyuyang19@fudan.edu.cn
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Subject: Re: [PATCH] net/tls: Fix sk_psock refcnt leak when in
 tls_data_ready()
From:   David Miller <davem@davemloft.net>
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From: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Date: Sat, 25 Apr 2020 21:10:23 +0800

> tls_data_ready() invokes sk_psock_get(), which returns a reference of
> the specified sk_psock object to "psock" with increased refcnt.
> 
> When tls_data_ready() returns, local variable "psock" becomes invalid,
> so the refcount should be decreased to keep refcount balanced.
> 
> The reference counting issue happens in one exception handling path of
> tls_data_ready(). When "psock->ingress_msg" is empty but "psock" is not
> NULL, the function forgets to decrease the refcnt increased by
> sk_psock_get(), causing a refcnt leak.
> 
> Fix this issue by calling sk_psock_put() on all paths when "psock" is
> not NULL.
> 
> Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>

Applied and queued up for -stable.