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author | Juntong Deng <juntong.deng@outlook.com> | 2024-08-28 20:48:11 +0100 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2024-08-28 17:11:54 -0700 |
commit | f633919d132cf1755d62278c989124c0ce23950f (patch) | |
tree | b3b6c0ab0e1c140480f33b8d4218de072f6a06ab /tools/testing/selftests/bpf/prog_tests/nested_trust.c | |
parent | c264487e5410e5a72db8a414566ab7d144223e6c (diff) |
bpf: Relax KF_ACQUIRE kfuncs strict type matching constraint
Currently we cannot pass zero offset (implicit cast) or non-zero offset
pointers to KF_ACQUIRE kfuncs. This is because KF_ACQUIRE kfuncs
requires strict type matching, but zero offset or non-zero offset does
not change the type of pointer, which causes the ebpf program to be
rejected by the verifier.
This can cause some problems, one example is that bpf_skb_peek_tail
kfunc [0] cannot be implemented by just passing in non-zero offset
pointers. We cannot pass pointers like &sk->sk_write_queue (non-zero
offset) or &sk->__sk_common (zero offset) to KF_ACQUIRE kfuncs.
This patch makes KF_ACQUIRE kfuncs not require strict type matching.
[0]: https://lore.kernel.org/bpf/AM6PR03MB5848CA39CB4B7A4397D380B099B12@AM6PR03MB5848.eurprd03.prod.outlook.com/
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Link: https://lore.kernel.org/r/AM6PR03MB5848FD2BD89BF0B6B5AA3B4C99952@AM6PR03MB5848.eurprd03.prod.outlook.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/nested_trust.c')
0 files changed, 0 insertions, 0 deletions