Re: [PATCH v16 04/12] bpf: Export bpf_dynptr_get_size()

From: Kumar Kartikeya Dwivedi
Date: Mon Sep 05 2022 - 22:34:42 EST


On Mon, 5 Sept 2022 at 16:35, Roberto Sassu
<roberto.sassu@xxxxxxxxxxxxxxx> wrote:
>
> From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
>
> Export bpf_dynptr_get_size(), so that kernel code dealing with eBPF dynamic
> pointers can obtain the real size of data carried by this data structure.
>
> Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> Reviewed-by: Joanne Koong <joannelkoong@xxxxxxxxx>
> Acked-by: KP Singh <kpsingh@xxxxxxxxxx>
> ---

Acked-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>

> include/linux/bpf.h | 1 +
> kernel/bpf/helpers.c | 2 +-
> 2 files changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index 9c1674973e03..9dbd7c3f8929 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -2585,6 +2585,7 @@ void bpf_dynptr_init(struct bpf_dynptr_kern *ptr, void *data,
> enum bpf_dynptr_type type, u32 offset, u32 size);
> void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr);
> int bpf_dynptr_check_size(u32 size);
> +u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr);
>
> #ifdef CONFIG_BPF_LSM
> void bpf_cgroup_atype_get(u32 attach_btf_id, int cgroup_atype);
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index fc08035f14ed..824864ac82d1 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -1408,7 +1408,7 @@ static void bpf_dynptr_set_type(struct bpf_dynptr_kern *ptr, enum bpf_dynptr_typ
> ptr->size |= type << DYNPTR_TYPE_SHIFT;
> }
>
> -static u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr)
> +u32 bpf_dynptr_get_size(struct bpf_dynptr_kern *ptr)
> {
> return ptr->size & DYNPTR_SIZE_MASK;
> }
> --
> 2.25.1
>