From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [patch net-next RFC 1/9] net_sch: red: Add offload ability to
 RED qdisc
Date: Tue, 31 Oct 2017 16:03:23 +0100
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To: David Ahern <dsahern@gmail.com>
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Tue, Oct 31, 2017 at 03:59:08PM CET, dsahern@gmail.com wrote:
>On 10/31/17 1:41 AM, Jiri Pirko wrote:
>>>
>>> If it is read-only, then attempts to set it from userspace should cause
>>> the command to fail.
>> 
>> That breaks uapi. Consider existing userspace app sending garbage in
>> that bit and new kernel which randomly fails upon the garbage.
>> 
>
>It is called syzkaller. The kernel should always validate userspace
>config including checking that unused bits are 0. So you are saying tc
>has never done that checking and just ignored bits that are not valid?

Not sure if in 100% of cases but in this case, yes.