On Mon, Nov 8, 2021 at 6:16 PM Hao Luo <haoluo@xxxxxxxxxx> wrote:
>
> Remove ARG_CONST_SIZE_OR_ZERO and use flag to mark that the
> argument may be zero.
>
> Signed-off-by: Hao Luo <haoluo@xxxxxxxxxx>
> ---
> include/linux/bpf.h | 2 -
> kernel/bpf/helpers.c | 20 +++++++--
> kernel/bpf/ringbuf.c | 5 ++-
> kernel/bpf/stackmap.c | 15 +++++--
> kernel/bpf/verifier.c | 8 ++--
> kernel/trace/bpf_trace.c | 90 ++++++++++++++++++++++++++++++++--------
> net/core/filter.c | 35 ++++++++++++----
> 7 files changed, 135 insertions(+), 40 deletions(-)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index dd92418814b5..27f81989f992 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -323,8 +323,6 @@ struct bpf_arg_type {
> */
>
> ARG_CONST_SIZE, /* number of bytes accessed from memory */
> - ARG_CONST_SIZE_OR_ZERO, /* number of bytes accessed from memory or 0 */
> -
> ARG_PTR_TO_CTX, /* pointer to context */
> ARG_PTR_TO_CTX_OR_NULL, /* pointer to context or NULL */
> ARG_ANYTHING, /* any (initialized) argument is ok */
> diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
> index cd792777afb2..082a8620f666 100644
> --- a/kernel/bpf/helpers.c
> +++ b/kernel/bpf/helpers.c
> @@ -631,7 +631,10 @@ const struct bpf_func_proto bpf_event_output_data_proto = {
> .arg2 = { .type = ARG_CONST_MAP_PTR },
> .arg3 = { .type = ARG_ANYTHING },
> .arg4 = { .type = ARG_PTR_TO_MEM },
> - .arg5 = { .type = ARG_CONST_SIZE_OR_ZERO },
> + .arg5 = {
> + .type = ARG_CONST_SIZE,
> + .flag = ARG_FLAG_MAYBE_NULL,
wait, OR_NULL and OR_ZERO isn't exactly the same thing... why are we
conflating them?
> + },
> };
>
> BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size,
[...]
