Re: [PATCH 3/5] tracing: Check that the synthetic event and field names are legal
From: Masami Hiramatsu
Date: Sat Oct 10 2020 - 18:59:08 EST
On Fri, 9 Oct 2020 10:17:09 -0500
Tom Zanussi <zanussi@xxxxxxxxxx> wrote:
> Call the is_good_name() function used by probe events to make sure
> synthetic event and field names don't contain illegal characters and
> cause unexpected parsing of synthetic event commands.
>
I've tested it. This looks good to me.
/sys/kernel/debug/tracing # echo "myevent char str]" >> synthetic_events
sh: write error: Invalid argument
/sys/kernel/debug/tracing # echo "myevent char str;[]" >> synthetic_events
sh: write error: Invalid argument
It works correctly now :)
Reviewed-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Tested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Thanks!
> Fixes: 4b147936fa50 (tracing: Add support for 'synthetic' events)
> Reported-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Signed-off-by: Tom Zanussi <zanussi@xxxxxxxxxx>
> ---
> kernel/trace/trace_events_synth.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
> index b19e2f4159ab..8c9d6e464da0 100644
> --- a/kernel/trace/trace_events_synth.c
> +++ b/kernel/trace/trace_events_synth.c
> @@ -572,6 +572,10 @@ static struct synth_field *parse_synth_field(int argc, const char **argv,
> ret = -ENOMEM;
> goto free;
> }
> + if (!is_good_name(field->name)) {
> + ret = -EINVAL;
> + goto free;
> + }
>
> if (field_type[0] == ';')
> field_type++;
> @@ -1112,6 +1116,11 @@ static int __create_synth_event(int argc, const char *name, const char **argv)
>
> mutex_lock(&event_mutex);
>
> + if (!is_good_name(name)) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> event = find_synth_event(name);
> if (event) {
> ret = -EEXIST;
> --
> 2.17.1
>
--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>