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Date: Wed, 24 Apr 2024 12:40:42 +0200
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To: Kunwu Chan <chentao@kylinos.cn>, bpf@vger.kernel.org,
 linux-kselftest@vger.kernel.org, kernel-janitors@vger.kernel.org,
 Alexei Starovoitov <ast@kernel.org>, Andrii Nakryiko <andrii@kernel.org>,
 Daniel Borkmann <daniel@iogearbox.net>, Eduard Zingerman
 <eddyz87@gmail.com>, Hao Luo <haoluo@google.com>,
 Jiri Olsa <jolsa@kernel.org>, John Fastabend <john.fastabend@gmail.com>,
 KP Singh <kpsingh@kernel.org>, Martin KaFai Lau <martin.lau@linux.dev>,
 Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>,
 Song Liu <song@kernel.org>, Stanislav Fomichev <sdf@google.com>,
 Yonghong Song <yonghong.song@linux.dev>
Cc: LKML <linux-kernel@vger.kernel.org>, Kunwu Chan <kunwu.chan@hotmail.com>
References: <20240424020444.2375773-4-chentao@kylinos.cn>
Subject: Re: [PATCH bpf-next 3/4] selftests/bpf: Add a null pointer check for
 the load_btf_spec
Content-Language: en-GB
From: Markus Elfring <Markus.Elfring@web.de>
In-Reply-To: <20240424020444.2375773-4-chentao@kylinos.cn>
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=E2=80=A6
> Add the malloc failure checking to avoid possible null
> dereference.
=E2=80=A6

How do you think about the following wording variant?

   Add a return value check so that a null pointer dereference will be avo=
ided
   after a memory allocation failure.


Would you like to add the tag =E2=80=9CFixes=E2=80=9D accordingly?


=E2=80=A6
> +++ b/tools/testing/selftests/bpf/test_verifier.c
> @@ -762,6 +762,8 @@ static int load_btf_spec(__u32 *types, int types_len=
,
>  	);
>
>  	raw_btf =3D malloc(sizeof(hdr) + types_len + strings_len);
> +	if (!raw_btf)
> +		return -ENOMEM;
=E2=80=A6

How do you think about to reuse the variable =E2=80=9Cerrno=E2=80=9D in su=
ch an error case?

Regards,
Markus