Re: [PATCH v4.1 - 5.1/8] libtracefs: Use the permissions of the instances directory for instances

[Tzvetomir Stoyanov <tz.stoyanov@gmail.com>]

On Wed, Nov 18, 2020 at 11:46 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> From: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>
>
> Use the same permissions of the instances directory for the permissions of
> creating a new instance.
>
> Link: https://lore.kernel.org/linux-trace-devel/20201117074557.180602-6-tz.stoyanov@gmail.com
>
> Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
> ---
>  lib/tracefs/tracefs-instance.c | 28 +++++++++++++++++++++++++---
>  1 file changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/lib/tracefs/tracefs-instance.c b/lib/tracefs/tracefs-instance.c
> index 06f33c35..13ec4f5f 100644
> --- a/lib/tracefs/tracefs-instance.c
> +++ b/lib/tracefs/tracefs-instance.c
> @@ -57,6 +57,25 @@ void tracefs_instance_free(struct tracefs_instance *instance)
>         free(instance);
>  }
>
> +static mode_t get_trace_file_permissions(char *name)
> +{
> +       mode_t rmode = 0;
> +       struct stat st;
> +       char *path;
> +       int ret;
> +
> +       path = tracefs_get_tracing_file(name);
> +       if (!path)
> +               return 0;
> +       ret = stat(path, &st);
> +       if (ret)
> +               goto out;
> +       rmode = st.st_mode & ACCESSPERMS;
> +out:
> +       tracefs_put_tracing_file(path);
> +       return rmode;
> +}
> +
>  /**
>   * tracefs_instance_create - Create a new ftrace instance
>   * @instance: Pointer to the instance to be created
> @@ -67,15 +86,18 @@ void tracefs_instance_free(struct tracefs_instance *instance)
>  int tracefs_instance_create(struct tracefs_instance *instance)
>  {
>         struct stat st;
> +       mode_t mode;
>         char *path;
>         int ret;
>
>         path = tracefs_instance_get_dir(instance);
>         ret = stat(path, &st);
> -       if (ret < 0)
> -               ret = mkdir(path, 0777);
> -       else
> +       if (ret < 0) {
> +               mode = get_trace_file_permissions("instances");
> +               ret = mkdir(path, mode);
> +       } else {
>                 ret = 1;
> +       }
>         tracefs_put_tracing_file(path);
>         return ret;
>  }
> --
> 2.25.4
>
I'm OK with that split.
Thanks, Steven!

Acked-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>

-- 
Tzvetomir (Ceco) Stoyanov
VMware Open Source Technology Center