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

From: Google
Date: Wed Sep 24 2025 - 10:28:15 EST


I think this should be backported to stable.

On Fri, 19 Sep 2025 10:15:56 +0900
"Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx> wrote:

> From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>

Fixes: 17911ff38aa5 ("tracing: Add locked_down checks to the open calls of files created for tracefs")
Cc: stable@xxxxxxxxxxxxxxx

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) <mhiramat@xxxxxxxxxx>