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Date:   Mon, 23 May 2022 10:23:22 -0700
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Subject: Re: [PATCH ipsec] Revert "net: af_key: add check for pfkey_broadcast
 in function pfkey_process"
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To:     Michal Kubecek <mkubecek@suse.cz>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        netdev@vger.kernel.org
Cc:     Jiasheng Jiang <jiasheng@iscas.ac.cn>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, linux-kernel@vger.kernel.org
References: <fbb31dc72fb38a69a2aca6c25f1be71d6a8bcc96.1653321424.git.mkubecek@suse.cz>
From:   Florian Fainelli <f.fainelli@gmail.com>
In-Reply-To: <fbb31dc72fb38a69a2aca6c25f1be71d6a8bcc96.1653321424.git.mkubecek@suse.cz>
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On 5/23/22 09:01, Michal Kubecek wrote:
> This reverts commit 4dc2a5a8f6754492180741facf2a8787f2c415d7.
> 
> A non-zero return value from pfkey_broadcast() does not necessarily mean
> an error occurred as this function returns -ESRCH when no registered
> listener received the message. In particular, a call with
> BROADCAST_PROMISC_ONLY flag and null one_sk argument can never return
> zero so that this commit in fact prevents processing any PF_KEY message.
> One visible effect is that racoon daemon fails to find encryption
> algorithms like aes and refuses to start.
> 
> Excluding -ESRCH return value would fix this but it's not obvious that
> we really want to bail out here and most other callers of
> pfkey_broadcast() also ignore the return value. Also, as pointed out by
> Steffen Klassert, PF_KEY is kind of deprecated and newer userspace code
> should use netlink instead so that we should only disturb the code for
> really important fixes.
> 
> Signed-off-by: Michal Kubecek <mkubecek@suse.cz>

Maybe you can add a comment above the call such that future tool-based 
patches submissions to give the author a chance to read the comment 
above and ask oneself twice whether this is relevant or not?
-- 
Florian