On Mon, Aug 24, 2020 at 03:10:34PM -0700, Khazhismel Kumykov wrote:
> CAP_SYS_ADMIN is too broad, and ionice fits into CAP_SYS_NICE's grouping.
>
> Retain CAP_SYS_ADMIN permission for backwards compatibility.
>
> Signed-off-by: Khazhismel Kumykov <khazhy@xxxxxxxxxx>
Acked-by: Serge Hallyn <serge@xxxxxxxxxx>
> ---
> block/ioprio.c | 2 +-
> include/uapi/linux/capability.h | 2 ++
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> v2: fix embarrassing logic mistake
> diff --git a/block/ioprio.c b/block/ioprio.c
> index 77bcab11dce5..276496246fe9 100644
> --- a/block/ioprio.c
> +++ b/block/ioprio.c
> @@ -69,7 +69,7 @@ int ioprio_check_cap(int ioprio)
>
> switch (class) {
> case IOPRIO_CLASS_RT:
> - if (!capable(CAP_SYS_ADMIN))
> + if (!capable(CAP_SYS_NICE) && !capable(CAP_SYS_ADMIN))
> return -EPERM;
> /* fall through */
> /* rt has prio field too */
> diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h
> index 395dd0df8d08..c6ca33034147 100644
> --- a/include/uapi/linux/capability.h
> +++ b/include/uapi/linux/capability.h
> @@ -288,6 +288,8 @@ struct vfs_ns_cap_data {
> processes and setting the scheduling algorithm used by another
> process. */
> /* Allow setting cpu affinity on other processes */
> +/* Allow setting realtime ioprio class */
> +/* Allow setting ioprio class on other processes */
>
> #define CAP_SYS_NICE 23
>
> --
> 2.28.0.297.g1956fa8f8d-goog
