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From:   Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= <toke@kernel.org>
To:     Rong Tao <rtoax@foxmail.com>, andrii.nakryiko@gmail.com,
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Subject: Re: [PATCH bpf-next v2] selftests/bpf: Fix error: undeclared
 identifier 'NF_NAT_MANIP_SRC'
In-Reply-To: <tencent_4C0B445E0305A18FACA04B4A959B57835107@qq.com>
References: <CAEf4BzZE5=OOp6OesB=P8PE=Ps62fkecDSZ9MzwHCD68=+oN0g@mail.gmail.com>
 <tencent_4C0B445E0305A18FACA04B4A959B57835107@qq.com>
Date:   Fri, 18 Nov 2022 12:08:09 +0100
Message-ID: <87mt8oy0yu.fsf@toke.dk>
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Rong Tao <rtoax@foxmail.com> writes:

> From: Rong Tao <rongtao@cestc.cn>
>
> commit 472caa69183f("netfilter: nat: un-export nf_nat_used_tuple")
> introduce NF_NAT_MANIP_SRC/DST enum in include/net/netfilter/nf_nat.h,
> and commit b06b45e82b59("selftests/bpf: add tests for bpf_ct_set_nat_info
> kfunc") use NF_NAT_MANIP_SRC/DST in test_bpf_nf.c.
>
> In bpf kself-test config (tools/testing/selftests/bpf/config) nf_nat
> is compiled as built-in, this issue occurs just if it is compiled as
> module. we just hardcode 1/0 here.
>
> How to reproduce the error:
>
>    $ make -C tools/testing/selftests/bpf/
>    ...
>       CLNG-BPF [test_maps] test_bpf_nf.bpf.o
>       error: use of undeclared identifier 'NF_NAT_MANIP_SRC'
>             bpf_ct_set_nat_info(ct, &saddr, sport, NF_NAT_MANIP_SRC);
>                                                          ^
>       error: use of undeclared identifier 'NF_NAT_MANIP_DST'
>             bpf_ct_set_nat_info(ct, &daddr, dport, NF_NAT_MANIP_DST);
>                                                          ^
>    2 errors generated.
>
> Signed-off-by: Rong Tao <rongtao@cestc.cn>

This will fix the compilation, but the selftest won't actually work when
nf_nat is compiled as a module (see [0]). Would be better to fix the
test properly instead of just papering over the compilation issue like
this. That requires a bit more surgery to the selftests, though...

-Toke

[0] https://lore.kernel.org/r/87leoh372s.fsf@toke.dk