On Mon, 2024-06-17 at 13:43 +0000, Matt Bobrowski wrote: [...] > * For OBJ_RELEASE and KF_RELEASE BPF helpers and kfuncs: > > * If the expected argument type is of an untyped pointer i.e. void *, > then we continue to enforce a zero fixed offset as we need to > ensure that the correct referenced pointer is handed off correctly > to the relevant deallocation routine > > * If the expected argument is backed by BTF, then we relax the strict > zero fixed offset and allow it only if we successfully type matched > between the register and argument. A failed type match between > register and argument will result in the legacy strict zero offset > semantics > > * For KF_TRUSTED_ARGS BPF kfuncs: > > * The fixed zero offset constraint has been lifted, such that > KF_TRUSTED_ARGS BPF kfuncs can now accept a trusted pointer > argument with a non-zero fixed offset providing that register and > argument BTF has type matched successfully [...] Hi Matt, I've read this and the next patch once, but need more time to provide feedback. Two quick notes: - It seems something is wrong with the way this patch set was sent: for some reason it is not organized as a single thread (e.g. on vger). - I see how OBJ_RELEASE arguments trigger btf_struct_ids_match() in check_release_arg_reg_off(), but I don't see how KF_TRUSTED_ARGS trigger similar logic. Do you have some positive tests that verify newly added functionality? Thanks, Eduard
