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Date: Thu, 4 Jan 2024 07:57:42 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Dmitry Safonov <dima@arista.com>
Cc: Eric Dumazet <edumazet@google.com>, "David S. Miller"
 <davem@davemloft.net>, Paolo Abeni <pabeni@redhat.com>, Christian Kujau
 <lists@nerdbynature.de>, Salam Noureddine <noureddine@arista.com>, Dmitry
 Safonov <0x7f454c46@gmail.com>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net/tcp: Only produce AO/MD5 logs if there are any keys
Message-ID: <20240104075742.71e4399f@kernel.org>
In-Reply-To: <20240104-tcp_hash_fail-logs-v1-1-ff3e1f6f9e72@arista.com>
References: <20240104-tcp_hash_fail-logs-v1-1-ff3e1f6f9e72@arista.com>
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On Thu,  4 Jan 2024 13:42:39 +0000 Dmitry Safonov wrote:
> User won't care about inproper hash options in the TCP header if they
> don't use neither TCP-AO nor TCP-MD5. Yet, those logs can add up in
> syslog, while not being a real concern to the host admin:
> > kernel: TCP: TCP segment has incorrect auth options set for XX.20.239.12.54681->XX.XX.90.103.80 [S]  
> 
> Keep silent and avoid logging when there aren't any keys in the system.
> 
> Side-note: I also defined static_branch_tcp_*() helpers to avoid more
> ifdeffery, going to remove more ifdeffery further with their help.

Wouldn't we be better off converting the prints to trace points. 
The chances for hitting them due to malicious packets feels much
higher than dealing with a buggy implementation in the wild.