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To: Ryan Mounce <ryan@mounce.com.au>
Cc: Cake List <cake@lists.bufferbloat.net>
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Date: Thu, 26 Apr 2018 08:39:33 +0200
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Subject: Re: [Cake] CAKE upstreaming - testers wanted,
	ACK filtering rescuers needed
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Ryan Mounce <ryan@mounce.com.au> writes:

> I'll investigate making the ACK filtering code safe, it is my mess after all :)
>
> Eric obviously understands this stuff a lot better than me, it looks
> like there are two issues?
> - Lack of minimum length check for TCP header, should be fairly
> straight-forward to fix
> - The possibility of unsafely filtering part of a split GSO
> super-packet?

The issue with the ACK filter in relation to GSO was just that a GSO
segment can't contain pure ACKs, so there's no reason to check after
splitting. I've already removed that part, so it's just the length
issue. I think it's just a matter of finding the length and calling
pskb_may_pull() (and aborting if that returns false).

-Toke