[v4] bpf: Allow access to const void pointer arguments in tracing programs

[PATCH bpf-next v4 0/2] bpf: Allow access to const void pointer arguments in tracing programs

KaFai Wan posted 2 patches 7 months, 4 weeks ago

Diff against v1 v2 v3
Download series mbox

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(-)

Expand all Fold all

[PATCH bpf-next v4 0/2] bpf: Allow access to const void pointer arguments in tracing programs

Posted by KaFai Wan 7 months, 4 weeks ago

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:
v3->v4: Addressed comments from Alexei Starovoitov
- change SOB to match From email address
- add Acked-by from jirka
Details in here:
https://lore.kernel.org/all/20250417151548.1276279-1-kafai.wan@hotmail.com/

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@hotmail.com/

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@hotmail.com/

-- 
2.43.0