bpf: Allow kfuncs return 'void *'

Recognize return of 'void *' from kfunc as returning unknown scalar.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-2-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
This commit is contained in:
Alexei Starovoitov 2024-03-06 19:12:23 -08:00 committed by Martin KaFai Lau
parent e63985ecd2
commit 88d1d4a7ee
1 changed files with 3 additions and 0 deletions

View File

@ -12364,6 +12364,9 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
meta.func_name);
return -EFAULT;
}
} else if (btf_type_is_void(ptr_type)) {
/* kfunc returning 'void *' is equivalent to returning scalar */
mark_reg_unknown(env, regs, BPF_REG_0);
} else if (!__btf_type_is_struct(ptr_type)) {
if (!meta.r0_size) {
__u32 sz;