On Wed, 25 Jul 2018 12:40:08 -0400
Steven Rostedt <rost...@goodmis.org> wrote:
> Hmm, looks to me that event_enable_trigger_func() suffers the same
> issue. Perhaps we should add this patch too:
>
> -- Steve
>
> diff --git a/kernel/trace/trace_events_trigger.c
> b/kernel/trace/trace_events_trigger.c
> index d18ec0e58be2..2681d917f896 100644
> --- a/kernel/trace/trace_events_trigger.c
> +++ b/kernel/trace/trace_events_trigger.c
> @@ -1457,6 +1457,10 @@ int event_enable_trigger_func(struct event_command
> *cmd_ops,
> ret = trace_event_enable_disable(event_enable_file, 1, 1);
> if (ret < 0)
> goto out_put;
> +
> + /* Up the trigger_data count to make sure reg doesn't free it on
> failure */
> + event_trigger_init(trigger_ops, trigger_data);
> +
> ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
> /*
> * The above returns on success the # of functions enabled,
> @@ -1464,12 +1468,13 @@ int event_enable_trigger_func(struct event_command
> *cmd_ops,
> * Consider no functions a failure too.
> */
> if (!ret) {
> + cmd_ops->unreg(glob, trigger_ops, trigger_data, file);
> ret = -ENOENT;
> - goto out_disable;
> - } else if (ret < 0)
> - goto out_disable;
> - /* Just return zero, not the number of enabled functions */
> - ret = 0;
> + } else if (ret > 0)
> + ret = 0;
> +
> + /* Down the counter of trigger_data or free it if not used anymore */
> + event_trigger_free(trigger_ops, trigger_data);
Nope, this doesn't work. It's a little more complex than the other one.
I'll just leave it, and fix the reg code for 4.19.
-- Steve
> out:
> return ret;
>
