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Subject: Re: [PATCH][bpf-next] bpf: verifier: avoid fall-through warnings
To:     "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>, Yonghong Song <yhs@fb.com>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Lawrence Brakmo <brakmo@fb.com>
Cc:     netdev@vger.kernel.org, bpf@vger.kernel.org,
        linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>
References: <20190711162233.GA6977@embeddedor>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <d3f4a4d3-e763-f146-8383-d5ef48d9d382@iogearbox.net>
Date:   Fri, 12 Jul 2019 15:41:27 +0200
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On 07/11/2019 06:22 PM, Gustavo A. R. Silva wrote:
> In preparation to enabling -Wimplicit-fallthrough, this patch silences
> the following warning:
> 
> kernel/bpf/verifier.c: In function ‘check_return_code’:
> kernel/bpf/verifier.c:6106:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
>    if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG ||
>       ^
> kernel/bpf/verifier.c:6109:2: note: here
>   case BPF_PROG_TYPE_CGROUP_SKB:
>   ^~~~
> 
> Warning level 3 was used: -Wimplicit-fallthrough=3
> 
> Notice that is much clearer to explicitly add breaks in each case
> statement (that actually contains some code), rather than letting
> the code to fall through.
> 
> This patch is part of the ongoing efforts to enable
> -Wimplicit-fallthrough.
> 
> Acked-by: Andrii Nakryiko <andriin@fb.com>
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

Looks good, applied to bpf, thanks.