Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Thu, 5 Jan 2023 10:47:15 -0800
In-Reply-To: <tencent_5695A257C4D16B4413036BA1DAACDECB0B07@qq.com>
Mime-Version: 1.0
References: <tencent_5695A257C4D16B4413036BA1DAACDECB0B07@qq.com>
Message-ID: <Y7cbM1D2YvB9tdqg@google.com>
Subject: Re: [PATCH bpf-next] libbpf: poison strlcpy()
From:   sdf@google.com
To:     Rong Tao <rtoax@foxmail.com>
Cc:     andrii@kernel.org, rongtao@cestc.cn,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>, Yonghong Song <yhs@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>, Hao Luo <haoluo@google.com>,
        Jiri Olsa <jolsa@kernel.org>,
        "open list:BPF [LIBRARY] (libbpf)" <bpf@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"; format=flowed; delsp=yes
Precedence: bulk

On 01/05, Rong Tao wrote:
> From: Rong Tao <rongtao@cestc.cn>

> Since commit 9fc205b413b3("libbpf: Add sane strncpy alternative and use
> it internally") introduce libbpf_strlcpy(), thus add strlcpy() to a poison
> list to prevent accidental use of it.

> Signed-off-by: Rong Tao <rongtao@cestc.cn>

Acked-by: Stanislav Fomichev <sdf@google.com>

> ---
>   tools/lib/bpf/libbpf_internal.h | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)

> diff --git a/tools/lib/bpf/libbpf_internal.h  
> b/tools/lib/bpf/libbpf_internal.h
> index 377642ff51fc..2d26ded383ca 100644
> --- a/tools/lib/bpf/libbpf_internal.h
> +++ b/tools/lib/bpf/libbpf_internal.h
> @@ -20,8 +20,8 @@
>   /* make sure libbpf doesn't use kernel-only integer typedefs */
>   #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64

> -/* prevent accidental re-addition of reallocarray() */
> -#pragma GCC poison reallocarray
> +/* prevent accidental re-addition of reallocarray()/strlcpy() */
> +#pragma GCC poison reallocarray strlcpy

>   #include "libbpf.h"
>   #include "btf.h"
> --
> 2.39.0