# Re: \[PATCH\] tracing: dynevent: Add a missing lockdown check on dynevent

- From: Masami Hiramatsu (Google) \<mhiramat@kernel.org\>
- Date: 2025-09-24 14:28:07 
- List: linux-trace-kernel
- Page: https://ratatoskr.run/linux-trace-kernel/2025/09/3229690
- Thread: https://ratatoskr.run/linux-trace-kernel/2025/09/3223086/t.md

```text
I think this should be backported to stable.

On Fri, 19 Sep 2025 10:15:56 +0900
"Masami Hiramatsu (Google)" [ref] wrote:

> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Since dynamic_events interface on tracefs is compatible with
> kprobe_events and uprobe_events, it should also check the lockdown
> status and reject if it is set.
> 
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Fixes: 17911ff38aa5 ("tracing: Add locked_down checks to the open calls of files created for tracefs")
Cc: <redacted>

Thanks,

> ---
>  kernel/trace/trace_dynevent.c |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
> index 5d64a18cacac..d06854bd32b3 100644
> --- a/kernel/trace/trace_dynevent.c
> +++ b/kernel/trace/trace_dynevent.c
> @@ -230,6 +230,10 @@ static int dyn_event_open(struct inode *inode, struct file *file)
>  {
>  	int ret;
>  
> +	ret = security_locked_down(LOCKDOWN_TRACEFS);
> +	if (ret)
> +		return ret;
> +
>  	ret = tracing_check_open_get_tr(NULL);
>  	if (ret)
>  		return ret;
> 


-- 
Masami Hiramatsu (Google) [ref]
```