Re: [PATCH] net: linearizing skb when downgrade gso_size

[Herbert Xu]

On Tue, Jul 09, 2024 at 05:29:59PM -0400, Willem de Bruijn wrote:
>
> This is an unfortunate feature, but already exists.
> 
> It decreases gso_size to account for tunnel headers.

Growing the tunnel header is totally fine.  But you should not
decrease gso_size because of that.  Instead the correct course
of action is to drop the packet and generate an ICMP if it no
longer fits the MTU.

A router that resegments a TCP packet at the TCP-level (not IP)
is brain-dead.

Cheers,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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