Re: [PATCH] tracing/kprobe: Release kprobe print_fmt properly

From: Song Liu
Date: Mon Jul 09 2018 - 12:41:23 EST




> On Jul 9, 2018, at 7:19 AM, Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> We don't release tk->tp.call.print_fmt when destroying
> local uprobe. Also there's missing print_fmt kfree in
> create_local_trace_kprobe error path.
>
> Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU")
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>

Thanks for the fix!

Acked-by: Song Liu <songliubraving@xxxxxx>


> ---
> kernel/trace/trace_kprobe.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index daa81571b22a..21f718472942 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -1480,8 +1480,10 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
> }
>
> ret = __register_trace_kprobe(tk);
> - if (ret < 0)
> + if (ret < 0) {
> + kfree(tk->tp.call.print_fmt);
> goto error;
> + }
>
> return &tk->tp.call;
> error:
> @@ -1501,6 +1503,8 @@ void destroy_local_trace_kprobe(struct trace_event_call *event_call)
> }
>
> __unregister_trace_kprobe(tk);
> +
> + kfree(tk->tp.call.print_fmt);
> free_trace_kprobe(tk);
> }
> #endif /* CONFIG_PERF_EVENTS */
> --
> 2.17.1
>