Re: [PATCH bpf-next v4 2/2] selftests/bpf: Add trampolines single and multi-level pointer params test coverage

[Eduard Zingerman]

On Tue, 2026-03-03 at 20:54 +1100, Slava Imameev wrote:
> Single and multi-level pointer params and return value test coverage
> for BPF trampolines:
> - fentry/fexit programs covering struct and void double/triple
>   pointer parameters and return values
> - verifier context tests covering pointers as parameters, these
>   tests cover single and double pointers to int, enum 32 and 64,
>   void, function, and double pointers to struct, triple pointers
>   for void
> - verifier context tests covering single and double pointers to
>   float, to check proper error is returned as pointers to float
>   are not supported
> - verifier context tests covering pointers as return values
> - verifier context tests for lsm to check trusted parameters
>   handling
> - verifier context tests covering out-of-bound access after cast
> - verifier BPF helper tests to validate no change in verifier
>   behavior
> 
> Signed-off-by: Slava Imameev <slava.imameev@xxxxxxxxxxxxxxx>
> ---

Again, I probably miss a point, but with current implementation it
seems sufficient in verifier_ctx_ptr_param() to add one or two
tests accessing void** or similar and checking verification log
to validate that parameter has expected type scalar().
Why so many tests are necessary?

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