Re: [PATCH] tracing/eprobe: Fix alloc event dir failed when event name no set

[Google]

On Sun, 18 Sep 2022 20:29:08 +0800
Tao Chen <chentao.kernel@xxxxxxxxxxxxxxxxx> wrote:

> The event dir will alloc failed when event name no set, using the
> command:
> "echo "e:esys/ syscalls/sys_enter_openat file=\$filename:string"
> >> dynamic_events"
> It seems that dir name="syscalls/sys_enter_openat" is not allowed
> in debugfs. So just use the "sys_enter_openat" as the event name.

Good catch! 

> 
> Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace
> events")

But actually, this code was introduced by below commit, so Fixes tag
must be updated. (this is important because stable backport version
will be decided by this tag.)

Fixes: 95c104c378dc ("tracing: Auto generate event name when creating a group of events")

Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>

Thank you!

> Signed-off-by: Tao Chen <chentao.kernel@xxxxxxxxxxxxxxxxx>
> ---
>  kernel/trace/trace_eprobe.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
> index 1783e3478912..a8938e54cd34 100644
> --- a/kernel/trace/trace_eprobe.c
> +++ b/kernel/trace/trace_eprobe.c
> @@ -968,8 +968,7 @@ static int __trace_eprobe_create(int argc, const char *argv[])
>  	}
>  
>  	if (!event) {
> -		strscpy(buf1, argv[1], MAX_EVENT_NAME_LEN);
> -		sanitize_event_name(buf1);
> +		strscpy(buf1, sys_event, MAX_EVENT_NAME_LEN);
>  		event = buf1;
>  	}
>  
> -- 
> 2.32.0
> 


-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>