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From:   Hao Sun <sunhao.th@gmail.com>
Subject: [PATCH bpf-next 0/2] bpf: Fix incorrect immediate spill
Date:   Thu, 26 Oct 2023 17:13:09 +0200
Message-Id: <20231026-fix-check-stack-write-v1-0-6b325ef3ce7e@gmail.com>
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To:     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>,
        Eduard Zingerman <eddyz87@gmail.com>
Cc:     bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-kselftest@vger.kernel.org, Hao Sun <sunhao.th@gmail.com>
Precedence: bulk

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.

Signed-off-by: Hao Sun <sunhao.th@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

 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

Best regards,
-- 
Hao Sun <sunhao.th@gmail.com>