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The absent member zero check could then read outside the local struct_ops data and crash libbpf. Patch 1 rejects local bitfields before calculating the member data pointer. Patch 2 adds a negative test for a local bitfield absent from the kernel BTF type. AI assistance was used to prepare the messages. I independently reviewed the code and test results. Changes since v2: - Restore the local bitfield check from v1. - Drop general offset validation and the bpftool changes, which covered malformed BTF outside. - Describe the local struct_ops type and absent kernel member. - Keep the negative test and check the load result before the diagnostic. v2: https://lore.kernel.org/bpf/20260913145233.1446643-1-caomingpei@gmail.com/ v1: https://lore.kernel.org/bpf/20260910172340.1467764-1-caomingpei@gmail.com/ Mingpei CAO (2): libbpf: Reject local struct_ops bitfields before data access selftests/bpf: Test local struct_ops bitfield rejection tools/lib/bpf/libbpf.c | 9 ++++-- .../bpf/prog_tests/test_struct_ops_module.c | 32 +++++++++++++++++++ .../selftests/bpf/progs/struct_ops_module.c | 7 ++++ 3 files changed, 46 insertions(+), 2 deletions(-) base-commit: ee363e055895364039bf28348ff13c615afad4ba -- 2.43.0