Re: [RFC v3 7/8] binder: use __kernel_pid_t and __kernel_uid_t for userspace

[Todd Kjos <tkjos@google.com>]

On Wed, Mar 9, 2022 at 8:52 AM T.J. Mercier <tjmercier@google.com> wrote:
>
> The kernel interface should use types that the kernel defines instead of
> pid_t and uid_t, whose definiton is owned by libc. This fixes the header
> so that it can be included without first including sys/types.h.
>
> Signed-off-by: T.J. Mercier <tjmercier@google.com>
> ---
>  include/uapi/linux/android/binder.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/uapi/linux/android/binder.h b/include/uapi/linux/android/binder.h
> index 169fd5069a1a..aa28454dbca3 100644
> --- a/include/uapi/linux/android/binder.h
> +++ b/include/uapi/linux/android/binder.h
> @@ -289,8 +289,8 @@ struct binder_transaction_data {
>
>         /* General information about the transaction. */
>         __u32           flags;
> -       pid_t           sender_pid;
> -       uid_t           sender_euid;
> +       __kernel_pid_t  sender_pid;
> +       __kernel_uid_t  sender_euid;

Are we guaranteed that this does not affect the UAPI at all? Userspace
code using this definition will have to run with kernels using the old
definition and visa-versa.

>         binder_size_t   data_size;      /* number of bytes of data */
>         binder_size_t   offsets_size;   /* number of bytes of offsets */
>
> --
> 2.35.1.616.g0bdcbb4464-goog
>