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Date:   Wed, 14 Oct 2020 20:43:22 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Cc:     netdev@vger.kernel.org, Gerrit Renker <gerrit@erg.abdn.ac.uk>,
        "David S. Miller" <davem@davemloft.net>,
        Thadeu Lima de Souza Cascardo <cascardo@canonical.com>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        "Alexander A. Klimov" <grandmaster@al2klimov.de>,
        Kees Cook <keescook@chromium.org>,
        Eric Dumazet <edumazet@google.com>,
        Alexey Kodanev <alexey.kodanev@oracle.com>,
        dccp@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] dccp: ccid: move timers to struct dccp_sock
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        <20201013171849.236025-2-kleber.souza@canonical.com>
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On Tue, 13 Oct 2020 19:18:48 +0200 Kleber Sacilotto de Souza wrote:
> From: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> 
> When dccps_hc_tx_ccid is freed, ccid timers may still trigger. The reason
> del_timer_sync can't be used is because this relies on keeping a reference
> to struct sock. But as we keep a pointer to dccps_hc_tx_ccid and free that
> during disconnect, the timer should really belong to struct dccp_sock.
> 
> This addresses CVE-2020-16119.
> 
> Fixes: 839a6094140a (net: dccp: Convert timers to use timer_setup())

Presumably you chose this commit because the fix won't apply beyond it?
But it really fixes 2677d2067731 (dccp: don't free.. right?

> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>