On Mon, Jul 31, 2023 at 01:47:01PM -0700, Alexei Starovoitov wrote:
> Probably the following will be enough:
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index 56ce5008aedd..eb91cae0612a 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -2270,7 +2270,7 @@ __bpf_kfunc void *bpf_dynptr_slice(const struct
> bpf_dynptr_kern *ptr, u32 offset
> case BPF_DYNPTR_TYPE_XDP:
> {
> void *xdp_ptr = bpf_xdp_pointer(ptr->data, ptr->offset
> + offset, len);
> - if (xdp_ptr)
> + if (!IS_ERR_OR_NULL(xdp_ptr))
> return xdp_ptr;
Also please, add a comment to bpf_xdp_pointer() which explains what the
NULL return means. I couldn't figure it out.
>
> Also I've noticed:
> void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
> void *buf, unsigned long len, bool flush);
> #else /* CONFIG_NET */
> static inline void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
> {
> return NULL;
> }
>
> The latter is wrong.
This the only part which I thought I understood. :P How is this wrong?
regards,
dan carpenter
