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Message-ID: <707a9c4c001ca5efe8bf7db36e7341f308651451.camel@gmail.com>
Subject: Re: [PATCH bpf-next 0/2] bpf: Fix incorrect immediate spill
From:   Eduard Zingerman <eddyz87@gmail.com>
To:     Hao Sun <sunhao.th@gmail.com>, Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        John Fastabend <john.fastabend@gmail.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        Song Liu <song@kernel.org>,
        Yonghong Song <yonghong.song@linux.dev>,
        KP Singh <kpsingh@kernel.org>,
        Stanislav Fomichev <sdf@google.com>,
        Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>,
        Mykola Lysenko <mykolal@fb.com>, Shuah Khan <shuah@kernel.org>
Cc:     bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org
Date:   Fri, 27 Oct 2023 00:33:30 +0300
In-Reply-To: <20231026-fix-check-stack-write-v1-0-6b325ef3ce7e@gmail.com>
References: <20231026-fix-check-stack-write-v1-0-6b325ef3ce7e@gmail.com>
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On Thu, 2023-10-26 at 17:13 +0200, Hao Sun wrote:
> Immediate is incorrectly cast to u32 before being spilled, losing sign
> information. The range information is incorrect after load again. Fix
> immediate spill by remove the cast. The second patch add a test case
> for this.
>=20
> Signed-off-by: Hao Sun <sunhao.th@gmail.com>

Thank you for finding and fixing this issue.

Acked-by: Eduard Zingerman <eddyz87@gmail.com>

> ---
> Hao Sun (2):
>       bpf: Fix check_stack_write_fixed_off() to correctly spill imm
>       selftests/bpf: Add test for immediate spilled to stack
>=20
>  kernel/bpf/verifier.c                             |  2 +-
>  tools/testing/selftests/bpf/verifier/bpf_st_mem.c | 32 +++++++++++++++++=
++++++
>  2 files changed, 33 insertions(+), 1 deletion(-)
> ---
> base-commit: 399f6185a1c02f39bcadb8749bc2d9d48685816f
> change-id: 20231026-fix-check-stack-write-c40996694dfa
>=20
> Best regards,