netdev - Re: [PATCH bpf-next 3/5] selftests/bpf: don't mask result of bpf_csum_diff() in test

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <31b8ea3b-f765-43c0-9cee-49bc13064f04@gmx.de>
Date: Mon, 21 Oct 2024 15:01:01 +0200
From: Helge Deller <deller@....de>
To: Puranjay Mohan <puranjay@...nel.org>, Albert Ou <aou@...s.berkeley.edu>,
 Alexei Starovoitov <ast@...nel.org>,
 Andrew Morton <akpm@...ux-foundation.org>,
 Andrii Nakryiko <andrii@...nel.org>, bpf@...r.kernel.org,
 Daniel Borkmann <daniel@...earbox.net>, "David S. Miller"
 <davem@...emloft.net>, Eduard Zingerman <eddyz87@...il.com>,
 Eric Dumazet <edumazet@...gle.com>, Hao Luo <haoluo@...gle.com>,
 Jakub Kicinski <kuba@...nel.org>,
 "James E.J. Bottomley" <James.Bottomley@...senPartnership.com>,
 Jiri Olsa <jolsa@...nel.org>, John Fastabend <john.fastabend@...il.com>,
 KP Singh <kpsingh@...nel.org>, linux-kernel@...r.kernel.org,
 linux-parisc@...r.kernel.org, linux-riscv@...ts.infradead.org,
 Martin KaFai Lau <martin.lau@...ux.dev>, Mykola Lysenko <mykolal@...com>,
 netdev@...r.kernel.org, Palmer Dabbelt <palmer@...belt.com>,
 Paolo Abeni <pabeni@...hat.com>, Paul Walmsley <paul.walmsley@...ive.com>,
 Puranjay Mohan <puranjay12@...il.com>, Shuah Khan <shuah@...nel.org>,
 Song Liu <song@...nel.org>, Stanislav Fomichev <sdf@...ichev.me>,
 Yonghong Song <yonghong.song@...ux.dev>
Subject: Re: [PATCH bpf-next 3/5] selftests/bpf: don't mask result of
 bpf_csum_diff() in test_verifier

On 10/21/24 14:21, Puranjay Mohan wrote:
> The bpf_csum_diff() helper has been fixed to return a 16-bit value for
> all archs, so now we don't need to mask the result.
>
> ...
> --- a/tools/testing/selftests/bpf/progs/verifier_array_access.c
> +++ b/tools/testing/selftests/bpf/progs/verifier_array_access.c
> @@ -368,8 +368,7 @@ __naked void a_read_only_array_2_1(void)
>   	r4 = 0;						\
>   	r5 = 0;						\
>   	call %[bpf_csum_diff];				\
> -l0_%=:	r0 &= 0xffff;					\
> -	exit;						\
> +l0_%=:	exit;						\

Instead of dropping the masking, would it make sense to
check here if (r0 >> 16) == 0 ?

Helge