Re: [PATCH] tracing/probe: Fix same probe event argument matching

[Masami Hiramatsu]

Hi Srikar,

On Tue, 24 Sep 2019 17:19:06 +0530
Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx> wrote:

> Commit fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event")
> tries to reject a event which matches an already existing probe.
> 
> However it currently continues to match arguments and rejects adding a
> probe even when the arguments don't match. Fix this by only rejecting a
> probe if and only if all the arguments match.

Thank you for fixing!
This looks good to me.

Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

> 
> Fixes: fe60b0ce8e73 ("tracing/probe: Reject exactly same probe event")
> Signed-off-by: Srikar Dronamraju <srikar@xxxxxxxxxxxxxxxxxx>
> ---
>  kernel/trace/trace_kprobe.c | 5 +++--
>  kernel/trace/trace_uprobe.c | 5 +++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index a6697e28ddda..402dc3ce88d3 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -549,10 +549,11 @@ static bool trace_kprobe_has_same_kprobe(struct trace_kprobe *orig,
>  		for (i = 0; i < orig->tp.nr_args; i++) {
>  			if (strcmp(orig->tp.args[i].comm,
>  				   comp->tp.args[i].comm))
> -				continue;
> +				break;
>  		}
>  
> -		return true;
> +		if (i == orig->tp.nr_args)
> +			return true;
>  	}
>  
>  	return false;
> diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
> index 34dd6d0016a3..dd884341f5c5 100644
> --- a/kernel/trace/trace_uprobe.c
> +++ b/kernel/trace/trace_uprobe.c
> @@ -431,10 +431,11 @@ static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
>  		for (i = 0; i < orig->tp.nr_args; i++) {
>  			if (strcmp(orig->tp.args[i].comm,
>  				   comp->tp.args[i].comm))
> -				continue;
> +				break;
>  		}
>  
> -		return true;
> +		if (i == orig->tp.nr_args)
> +			return true;
>  	}
>  
>  	return false;
> -- 
> 2.18.1
> 


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>