Files
linux/kernel
Amery Hung ba5b99470c bpf: Tag nullable kfunc pointer args with PTR_MAYBE_NULL
Now that get_kfunc_ptr_arg_type() classifies a kfunc pointer argument
from its BTF alone, express a nullable argument by OR-ing PTR_MAYBE_NULL
into the classified type, and resolve a NULL register after
classification instead of before it.

Previously check_kfunc_args() short-circuited a nullable argument passed
a NULL register with a continue placed before get_kfunc_ptr_arg_type(),
so the NULL never reached classification. That kept a register-state
decision (bpf_register_is_null()) ahead of the BTF-based classification.

This mirrors how helper arguments carry PTR_MAYBE_NULL in their
bpf_arg_type and is a step toward describing kfuncs with a bpf_func_proto:
the nullability now travels with the per-argument classification, so it is
captured when the prototype is generated at add-call time.

Signed-off-by: Amery Hung <ameryhung@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260801074633.1595644-17-ameryhung@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-08-03 00:31:25 +02:00
..
2026-06-02 15:36:06 +02:00
2025-10-29 10:29:54 +01:00
2026-01-26 19:07:13 -08:00