Re: [RFC PATCH 4/7] tracing/probe: Check event/group naming rule at parsing

[Steven Rostedt]

On Wed, 13 Mar 2019 21:28:12 +0900
Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:

> Check event and group naming rule at parsing it instead
> of allocating probes.
> 
> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> ---
>  kernel/trace/trace_kprobe.c |    7 +------
>  kernel/trace/trace_probe.c  |    8 ++++++++
>  kernel/trace/trace_uprobe.c |    5 +----
>  3 files changed, 10 insertions(+), 10 deletions(-)
> 
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index d47e12596f12..5222fd82e7e4 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -221,7 +221,7 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group,
>  
>  	tk->rp.maxactive = maxactive;
>  
> -	if (!event || !is_good_name(event)) {
> +	if (!event || !group) {
>  		ret = -EINVAL;
>  		goto error;
>  	}
> @@ -231,11 +231,6 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group,
>  	if (!tk->tp.call.name)
>  		goto error;
>  
> -	if (!group || !is_good_name(group)) {
> -		ret = -EINVAL;
> -		goto error;
> -	}
> -
>  	tk->tp.class.system = kstrdup(group, GFP_KERNEL);
>  	if (!tk->tp.class.system)
>  		goto error;
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> index feae03056f0b..1f0cb4030c0b 100644
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -172,6 +172,10 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
>  			return -E2BIG;
>  		}
>  		strlcpy(buf, event, slash - event + 1);
> +		if (!is_good_name(buf)) {
> +			pr_info("Group name must follow the rule of C identifier\n");

What do you mean by "C identifier"?

-- Steve

> +			return -EINVAL;
> +		}
>  		*pgroup = buf;
>  		*pevent = slash + 1;
>  		event = *pevent;
> @@ -184,6 +188,10 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
>  		pr_info("Event name is too long\n");
>  		return -E2BIG;
>  	}
> +	if (!is_good_name(event)) {
> +		pr_info("Event name must follow the rule of C identifier\n");
> +		return -EINVAL;
> +	}
>  	return 0;
>  }
>