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Date: Fri, 11 Jul 2025 15:36:05 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Oleksij Rempel <o.rempel@pengutronix.de>, "David S. Miller"
 <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Paolo Abeni
 <pabeni@redhat.com>, Simon Horman <horms@kernel.org>,
 kernel@pengutronix.de, linux-kernel@vger.kernel.org,
 netdev@vger.kernel.org, Maxime Chevallier <maxime.chevallier@bootlin.com>,
 lst@pengutronix.de
Subject: Re: [PATCH net-next v4 0/4] net: selftest: improve test string
 formatting and checksum handling
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On Fri, 11 Jul 2025 10:42:52 +0200 Marc Kleine-Budde wrote:
> Is passing packets with known bad checksums to the networking stack with
> CHECKSUM_NONE, so that the checksum is recalculated in software a
> potential DoS vector?

I'm not aware of it being a DoS vector. We're talking about a basic
arithmetic sum here, not a CRC or anything math-intensive. So if we
assume the CPU is fast enough to copy this data via the socket API
to user space it is definitely fast enough to add it up and drop 
a packet.