From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jakub Kicinski <kubakici@wp.pl>
Subject: Re: [PATCH bpf-next v4 03/10] bpf: btf: Check members of
 struct/union
Date: Wed, 18 Apr 2018 10:22:10 -0700
Message-ID: <20180418102210.5fbbb05e@cakuba.netronome.com>
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        <20180417204243.4028831-4-kafai@fb.com>
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Cc: <netdev@vger.kernel.org>, Alexei Starovoitov <ast@fb.com>,
        Daniel Borkmann <daniel@iogearbox.net>, <kernel-team@fb.com>
To: Martin KaFai Lau <kafai@fb.com>
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On Tue, 17 Apr 2018 13:42:36 -0700, Martin KaFai Lau wrote:
> This patch checks a few things of struct's members:
> 
> 1) It has a valid size (e.g. a "const void" is invalid)
> 2) A member's size (+ its member's offset) does not exceed
>    the containing struct's size.
> 3) The member's offset satisfies the alignment requirement

Could we also introduce a requirement for members to have different
names?  Maybe it's there but I missed it.  Would BTF with duplicated
member names be considered valid?

> The above can only be done after the needs_resolve member's type
> is resolved.  Hence, the above is done together in
> btf_struct_resolve().
> 
> Each possible member's type (e.g. int, enum, modifier...) implements
> the check_member() ops which will be called from btf_struct_resolve().
> 
> Signed-off-by: Martin KaFai Lau <kafai@fb.com>
> Acked-by: Alexei Starovoitov <ast@fb.com>