Re: [PATCH bpf-next v1 03/10] bpf: Verifier support for KF_IMPLICIT_ARGS

[Eduard Zingerman]

On Fri, 2026-01-09 at 10:48 -0800, Ihor Solodrai wrote:

[...]

> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
> @@ -3271,6 +3271,38 @@ static struct btf *find_kfunc_desc_btf(struct bpf_verifier_env *env, s16 offset)
>  	return btf_vmlinux ?: ERR_PTR(-ENOENT);
>  }
>  
> +#define KF_IMPL_SUFFIX "_impl"
> +
> +static const struct btf_type *find_kfunc_impl_proto(struct bpf_verifier_env *env,
> +						    struct btf *btf,
> +						    const char *func_name)
> +{
> +	char impl_name[KSYM_SYMBOL_LEN];

Oh, as we discussed already, this should use env->tmp_str_buf.

> +	const struct btf_type *func;
> +	s32 impl_id;
> +	int len;
> +
> +	len = snprintf(impl_name, sizeof(impl_name), "%s%s", func_name, KF_IMPL_SUFFIX);
> +	if (len < 0 || len >= sizeof(impl_name)) {
> +		verbose(env, "function name %s%s is too long\n", func_name, KF_IMPL_SUFFIX);
> +		return NULL;
> +	}

[...]