[PATCH bpf-next v3 0/2] bpf: Allow access to const void pointer arguments in tracing programs

From: KaFai Wan
Date: Thu Apr 17 2025 - 11:16:35 EST


If we try to access argument which is pointer to const void, it's an
UNKNOWN type, verifier will fail to load.

Use is_void_or_int_ptr to check if type is void or int pointer.
Add a selftest to check it.

---
KaFai Wan (2):
bpf: Allow access to const void pointer arguments in tracing programs
selftests/bpf: Add test to access const void pointer argument in
tracing program

kernel/bpf/btf.c | 13 +++----------
net/bpf/test_run.c | 8 +++++++-
.../selftests/bpf/progs/verifier_btf_ctx_access.c | 12 ++++++++++++
3 files changed, 22 insertions(+), 11 deletions(-)

Changelog:
v2->v3: Addressed comments from jirka
- remove duplicate checks for void pointer
Details in here:
https://lore.kernel.org/bpf/20250416161756.1079178-1-kafai.wan@xxxxxxxxxxx/

v1->v2: Addressed comments from jirka
- use btf_type_is_void to check if type is void
- merge is_void_ptr and is_int_ptr to is_void_or_int_ptr
- fix selftests
Details in here:
https://lore.kernel.org/all/20250412170626.3638516-1-kafai.wan@xxxxxxxxxxx/

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2.43.0